diff --git a/vendor/gopkg.in/Shopify/sarama.v1/.travis.yml b/vendor/gopkg.in/Shopify/sarama.v1/.travis.yml
index b7f7874..4331fa1 100644
--- a/vendor/gopkg.in/Shopify/sarama.v1/.travis.yml
+++ b/vendor/gopkg.in/Shopify/sarama.v1/.travis.yml
@@ -1,7 +1,8 @@
+dist: xenial
 language: go
 go:
-- 1.10.x
 - 1.11.x
+- 1.12.x
 
 env:
   global:
@@ -11,15 +12,16 @@
   - KAFKA_HOSTNAME=localhost
   - DEBUG=true
   matrix:
-  - KAFKA_VERSION=1.1.1 KAFKA_SCALA_VERSION=2.11
-  - KAFKA_VERSION=2.0.1 KAFKA_SCALA_VERSION=2.12
-  - KAFKA_VERSION=2.1.0 KAFKA_SCALA_VERSION=2.12
+  - KAFKA_VERSION=2.1.1 KAFKA_SCALA_VERSION=2.12
+  - KAFKA_VERSION=2.2.1 KAFKA_SCALA_VERSION=2.12
+  - KAFKA_VERSION=2.3.0 KAFKA_SCALA_VERSION=2.12
 
 before_install:
 - export REPOSITORY_ROOT=${TRAVIS_BUILD_DIR}
 - vagrant/install_cluster.sh
 - vagrant/boot_cluster.sh
 - vagrant/create_topics.sh
+- vagrant/run_java_producer.sh
 
 install: make install_dependencies
 
@@ -27,7 +29,7 @@
 - make test
 - make vet
 - make errcheck
-- if [[ "$TRAVIS_GO_VERSION" == 1.11* ]]; then make fmt; fi
+- if [[ "$TRAVIS_GO_VERSION" == 1.12* ]]; then make fmt; fi
 
 after_success:
 - bash <(curl -s https://codecov.io/bash)
diff --git a/vendor/gopkg.in/Shopify/sarama.v1/CHANGELOG.md b/vendor/gopkg.in/Shopify/sarama.v1/CHANGELOG.md
index 0e69c2d..4f89e21 100644
--- a/vendor/gopkg.in/Shopify/sarama.v1/CHANGELOG.md
+++ b/vendor/gopkg.in/Shopify/sarama.v1/CHANGELOG.md
@@ -1,5 +1,101 @@
 # Changelog
 
+#### Version 1.23.0 (2019-07-02)
+
+New Features:
+- Add support for Kafka 2.3.0
+  ([1418](https://github.com/Shopify/sarama/pull/1418)).
+- Add support for ListConsumerGroupOffsets v2
+  ([1374](https://github.com/Shopify/sarama/pull/1374)).
+- Add support for DeleteConsumerGroup
+  ([1417](https://github.com/Shopify/sarama/pull/1417)).
+- Add support for SASLVersion configuration
+  ([1410](https://github.com/Shopify/sarama/pull/1410)).
+- Add kerberos support
+  ([1366](https://github.com/Shopify/sarama/pull/1366)).
+
+Improvements:
+- Improve sasl_scram_client example
+  ([1406](https://github.com/Shopify/sarama/pull/1406)).
+- Fix shutdown and race-condition in consumer-group example
+  ([1404](https://github.com/Shopify/sarama/pull/1404)).
+- Add support for error codes 77—81
+  ([1397](https://github.com/Shopify/sarama/pull/1397)).
+- Pool internal objects allocated per message
+  ([1385](https://github.com/Shopify/sarama/pull/1385)).
+- Reduce packet decoder allocations
+  ([1373](https://github.com/Shopify/sarama/pull/1373)).
+- Support timeout when fetching metadata
+  ([1359](https://github.com/Shopify/sarama/pull/1359)).
+
+Bug Fixes:
+- Fix fetch size integer overflow
+  ([1376](https://github.com/Shopify/sarama/pull/1376)).
+- Handle and log throttled FetchResponses
+  ([1383](https://github.com/Shopify/sarama/pull/1383)).
+- Refactor misspelled word Resouce to Resource
+  ([1368](https://github.com/Shopify/sarama/pull/1368)).
+
+#### Version 1.22.1 (2019-04-29)
+
+Improvements:
+- Use zstd 1.3.8
+  ([1350](https://github.com/Shopify/sarama/pull/1350)).
+- Add support for SaslHandshakeRequest v1
+  ([1354](https://github.com/Shopify/sarama/pull/1354)).
+
+Bug Fixes:
+- Fix V5 MetadataRequest nullable topics array
+  ([1353](https://github.com/Shopify/sarama/pull/1353)).
+- Use a different SCRAM client for each broker connection
+  ([1349](https://github.com/Shopify/sarama/pull/1349)).
+- Fix AllowAutoTopicCreation for MetadataRequest greater than v3
+  ([1344](https://github.com/Shopify/sarama/pull/1344)).
+
+#### Version 1.22.0 (2019-04-09)
+
+New Features:
+- Add Offline Replicas Operation to Client
+  ([1318](https://github.com/Shopify/sarama/pull/1318)).
+- Allow using proxy when connecting to broker
+  ([1326](https://github.com/Shopify/sarama/pull/1326)).
+- Implement ReadCommitted
+  ([1307](https://github.com/Shopify/sarama/pull/1307)).
+- Add support for Kafka 2.2.0
+  ([1331](https://github.com/Shopify/sarama/pull/1331)).
+- Add SASL SCRAM-SHA-512 and SCRAM-SHA-256 mechanismes
+  ([1331](https://github.com/Shopify/sarama/pull/1295)).
+
+Improvements:
+- Unregister all broker metrics on broker stop
+  ([1232](https://github.com/Shopify/sarama/pull/1232)).
+- Add SCRAM authentication example
+  ([1303](https://github.com/Shopify/sarama/pull/1303)).
+- Add consumergroup examples
+  ([1304](https://github.com/Shopify/sarama/pull/1304)).
+- Expose consumer batch size metric
+  ([1296](https://github.com/Shopify/sarama/pull/1296)).
+- Add TLS options to console producer and consumer
+  ([1300](https://github.com/Shopify/sarama/pull/1300)).
+- Reduce client close bookkeeping
+  ([1297](https://github.com/Shopify/sarama/pull/1297)).
+- Satisfy error interface in create responses
+  ([1154](https://github.com/Shopify/sarama/pull/1154)).
+- Please lint gods
+  ([1346](https://github.com/Shopify/sarama/pull/1346)).
+
+Bug Fixes:
+- Fix multi consumer group instance crash
+  ([1338](https://github.com/Shopify/sarama/pull/1338)).
+- Update lz4 to latest version
+  ([1347](https://github.com/Shopify/sarama/pull/1347)).
+- Retry ErrNotCoordinatorForConsumer in new consumergroup session
+  ([1231](https://github.com/Shopify/sarama/pull/1231)).
+- Fix cleanup error handler
+  ([1332](https://github.com/Shopify/sarama/pull/1332)).
+- Fix rate condition in PartitionConsumer
+  ([1156](https://github.com/Shopify/sarama/pull/1156)).
+
 #### Version 1.21.0 (2019-02-24)
 
 New Features:
diff --git a/vendor/gopkg.in/Shopify/sarama.v1/Makefile b/vendor/gopkg.in/Shopify/sarama.v1/Makefile
index 09f743c..360b220 100644
--- a/vendor/gopkg.in/Shopify/sarama.v1/Makefile
+++ b/vendor/gopkg.in/Shopify/sarama.v1/Makefile
@@ -1,11 +1,12 @@
 export GO111MODULE=on
 
-default: fmt vet errcheck test
+default: fmt vet errcheck test lint
 
 # Taken from https://github.com/codecov/example-go#caveat-multiple-files
+.PHONY: test
 test:
 	echo "" > coverage.txt
-	for d in `go list ./... | grep -v vendor`; do \
+	for d in `go list ./...`; do \
 		go test -p 1 -v -timeout 240s -race -coverprofile=profile.out -covermode=atomic $$d || exit 1; \
 		if [ -f profile.out ]; then \
 			cat profile.out >> coverage.txt; \
@@ -13,20 +14,39 @@
 		fi \
 	done
 
+GOLINT := $(shell command -v golint)
+
+.PHONY: lint
+lint:
+ifndef GOLINT
+	go get golang.org/x/lint/golint
+endif
+	go list ./... | xargs golint
+
+.PHONY: vet
 vet:
 	go vet ./...
 
+ERRCHECK := $(shell command -v errcheck)
 # See https://github.com/kisielk/errcheck/pull/141 for details on ignorepkg
+.PHONY: errcheck
 errcheck:
+ifndef ERRCHECK
+	go get github.com/kisielk/errcheck
+endif
 	errcheck -ignorepkg fmt github.com/Shopify/sarama/...
 
+.PHONY: fmt
 fmt:
 	@if [ -n "$$(go fmt ./...)" ]; then echo 'Please run go fmt on your code.' && exit 1; fi
 
-install_dependencies: install_errcheck get
+.PHONY : install_dependencies
+install_dependencies: get
 
-install_errcheck:
-	go get github.com/kisielk/errcheck
-
+.PHONY: get
 get:
-	go get -t
+	go get -t -v ./...
+
+.PHONY: clean
+clean:
+	go clean ./...
diff --git a/vendor/gopkg.in/Shopify/sarama.v1/README.md b/vendor/gopkg.in/Shopify/sarama.v1/README.md
index f241b89..4cd736b 100644
--- a/vendor/gopkg.in/Shopify/sarama.v1/README.md
+++ b/vendor/gopkg.in/Shopify/sarama.v1/README.md
@@ -21,7 +21,7 @@
 Sarama provides a "2 releases + 2 months" compatibility guarantee: we support
 the two latest stable releases of Kafka and Go, and we provide a two month
 grace period for older releases. This means we currently officially support
-Go 1.8 through 1.11, and Kafka 1.0 through 2.0, although older releases are
+Go 1.11 through 1.12, and Kafka 2.0 through 2.3, although older releases are
 still likely to work.
 
 Sarama follows semantic versioning and provides API stability via the gopkg.in service.
diff --git a/vendor/gopkg.in/Shopify/sarama.v1/acl_bindings.go b/vendor/gopkg.in/Shopify/sarama.v1/acl_bindings.go
index b91c282..50b689d 100644
--- a/vendor/gopkg.in/Shopify/sarama.v1/acl_bindings.go
+++ b/vendor/gopkg.in/Shopify/sarama.v1/acl_bindings.go
@@ -1,9 +1,10 @@
 package sarama
 
+//Resource holds information about acl resource type
 type Resource struct {
-	ResourceType       AclResourceType
-	ResourceName       string
-	ResoucePatternType AclResourcePatternType
+	ResourceType        AclResourceType
+	ResourceName        string
+	ResourcePatternType AclResourcePatternType
 }
 
 func (r *Resource) encode(pe packetEncoder, version int16) error {
@@ -14,11 +15,11 @@
 	}
 
 	if version == 1 {
-		if r.ResoucePatternType == AclPatternUnknown {
+		if r.ResourcePatternType == AclPatternUnknown {
 			Logger.Print("Cannot encode an unknown resource pattern type, using Literal instead")
-			r.ResoucePatternType = AclPatternLiteral
+			r.ResourcePatternType = AclPatternLiteral
 		}
-		pe.putInt8(int8(r.ResoucePatternType))
+		pe.putInt8(int8(r.ResourcePatternType))
 	}
 
 	return nil
@@ -39,12 +40,13 @@
 		if err != nil {
 			return err
 		}
-		r.ResoucePatternType = AclResourcePatternType(pattern)
+		r.ResourcePatternType = AclResourcePatternType(pattern)
 	}
 
 	return nil
 }
 
+//Acl holds information about acl type
 type Acl struct {
 	Principal      string
 	Host           string
@@ -91,6 +93,7 @@
 	return nil
 }
 
+//ResourceAcls is an acl resource type
 type ResourceAcls struct {
 	Resource
 	Acls []*Acl
diff --git a/vendor/gopkg.in/Shopify/sarama.v1/acl_create_request.go b/vendor/gopkg.in/Shopify/sarama.v1/acl_create_request.go
index d3d5ad8..da1cdef 100644
--- a/vendor/gopkg.in/Shopify/sarama.v1/acl_create_request.go
+++ b/vendor/gopkg.in/Shopify/sarama.v1/acl_create_request.go
@@ -1,5 +1,6 @@
 package sarama
 
+//CreateAclsRequest is an acl creation request
 type CreateAclsRequest struct {
 	Version      int16
 	AclCreations []*AclCreation
@@ -38,16 +39,16 @@
 	return nil
 }
 
-func (d *CreateAclsRequest) key() int16 {
+func (c *CreateAclsRequest) key() int16 {
 	return 30
 }
 
-func (d *CreateAclsRequest) version() int16 {
-	return d.Version
+func (c *CreateAclsRequest) version() int16 {
+	return c.Version
 }
 
-func (d *CreateAclsRequest) requiredVersion() KafkaVersion {
-	switch d.Version {
+func (c *CreateAclsRequest) requiredVersion() KafkaVersion {
+	switch c.Version {
 	case 1:
 		return V2_0_0_0
 	default:
@@ -55,6 +56,7 @@
 	}
 }
 
+//AclCreation is a wrapper around Resource and Acl type
 type AclCreation struct {
 	Resource
 	Acl
diff --git a/vendor/gopkg.in/Shopify/sarama.v1/acl_create_response.go b/vendor/gopkg.in/Shopify/sarama.v1/acl_create_response.go
index 8a56f35..f5a5e9a 100644
--- a/vendor/gopkg.in/Shopify/sarama.v1/acl_create_response.go
+++ b/vendor/gopkg.in/Shopify/sarama.v1/acl_create_response.go
@@ -2,6 +2,7 @@
 
 import "time"
 
+//CreateAclsResponse is a an acl reponse creation type
 type CreateAclsResponse struct {
 	ThrottleTime         time.Duration
 	AclCreationResponses []*AclCreationResponse
@@ -46,18 +47,19 @@
 	return nil
 }
 
-func (d *CreateAclsResponse) key() int16 {
+func (c *CreateAclsResponse) key() int16 {
 	return 30
 }
 
-func (d *CreateAclsResponse) version() int16 {
+func (c *CreateAclsResponse) version() int16 {
 	return 0
 }
 
-func (d *CreateAclsResponse) requiredVersion() KafkaVersion {
+func (c *CreateAclsResponse) requiredVersion() KafkaVersion {
 	return V0_11_0_0
 }
 
+//AclCreationResponse is an acl creation response type
 type AclCreationResponse struct {
 	Err    KError
 	ErrMsg *string
diff --git a/vendor/gopkg.in/Shopify/sarama.v1/acl_delete_request.go b/vendor/gopkg.in/Shopify/sarama.v1/acl_delete_request.go
index 5e94ad7..15908ea 100644
--- a/vendor/gopkg.in/Shopify/sarama.v1/acl_delete_request.go
+++ b/vendor/gopkg.in/Shopify/sarama.v1/acl_delete_request.go
@@ -1,5 +1,6 @@
 package sarama
 
+//DeleteAclsRequest is a delete acl request
 type DeleteAclsRequest struct {
 	Version int
 	Filters []*AclFilter
diff --git a/vendor/gopkg.in/Shopify/sarama.v1/acl_delete_response.go b/vendor/gopkg.in/Shopify/sarama.v1/acl_delete_response.go
index a885fe5..6529565 100644
--- a/vendor/gopkg.in/Shopify/sarama.v1/acl_delete_response.go
+++ b/vendor/gopkg.in/Shopify/sarama.v1/acl_delete_response.go
@@ -2,21 +2,22 @@
 
 import "time"
 
+//DeleteAclsResponse is a delete acl response
 type DeleteAclsResponse struct {
 	Version         int16
 	ThrottleTime    time.Duration
 	FilterResponses []*FilterResponse
 }
 
-func (a *DeleteAclsResponse) encode(pe packetEncoder) error {
-	pe.putInt32(int32(a.ThrottleTime / time.Millisecond))
+func (d *DeleteAclsResponse) encode(pe packetEncoder) error {
+	pe.putInt32(int32(d.ThrottleTime / time.Millisecond))
 
-	if err := pe.putArrayLength(len(a.FilterResponses)); err != nil {
+	if err := pe.putArrayLength(len(d.FilterResponses)); err != nil {
 		return err
 	}
 
-	for _, filterResponse := range a.FilterResponses {
-		if err := filterResponse.encode(pe, a.Version); err != nil {
+	for _, filterResponse := range d.FilterResponses {
+		if err := filterResponse.encode(pe, d.Version); err != nil {
 			return err
 		}
 	}
@@ -24,22 +25,22 @@
 	return nil
 }
 
-func (a *DeleteAclsResponse) decode(pd packetDecoder, version int16) (err error) {
+func (d *DeleteAclsResponse) decode(pd packetDecoder, version int16) (err error) {
 	throttleTime, err := pd.getInt32()
 	if err != nil {
 		return err
 	}
-	a.ThrottleTime = time.Duration(throttleTime) * time.Millisecond
+	d.ThrottleTime = time.Duration(throttleTime) * time.Millisecond
 
 	n, err := pd.getArrayLength()
 	if err != nil {
 		return err
 	}
-	a.FilterResponses = make([]*FilterResponse, n)
+	d.FilterResponses = make([]*FilterResponse, n)
 
 	for i := 0; i < n; i++ {
-		a.FilterResponses[i] = new(FilterResponse)
-		if err := a.FilterResponses[i].decode(pd, version); err != nil {
+		d.FilterResponses[i] = new(FilterResponse)
+		if err := d.FilterResponses[i].decode(pd, version); err != nil {
 			return err
 		}
 	}
@@ -59,6 +60,7 @@
 	return V0_11_0_0
 }
 
+//FilterResponse is a filter response type
 type FilterResponse struct {
 	Err          KError
 	ErrMsg       *string
@@ -109,6 +111,7 @@
 	return nil
 }
 
+//MatchingAcl is a matching acl type
 type MatchingAcl struct {
 	Err    KError
 	ErrMsg *string
diff --git a/vendor/gopkg.in/Shopify/sarama.v1/acl_describe_request.go b/vendor/gopkg.in/Shopify/sarama.v1/acl_describe_request.go
index 3c95320..5222d46 100644
--- a/vendor/gopkg.in/Shopify/sarama.v1/acl_describe_request.go
+++ b/vendor/gopkg.in/Shopify/sarama.v1/acl_describe_request.go
@@ -1,5 +1,6 @@
 package sarama
 
+//DescribeAclsRequest is a secribe acl request type
 type DescribeAclsRequest struct {
 	Version int
 	AclFilter
diff --git a/vendor/gopkg.in/Shopify/sarama.v1/acl_describe_response.go b/vendor/gopkg.in/Shopify/sarama.v1/acl_describe_response.go
index db3a88c..12126e5 100644
--- a/vendor/gopkg.in/Shopify/sarama.v1/acl_describe_response.go
+++ b/vendor/gopkg.in/Shopify/sarama.v1/acl_describe_response.go
@@ -2,6 +2,7 @@
 
 import "time"
 
+//DescribeAclsResponse is a describe acl response type
 type DescribeAclsResponse struct {
 	Version      int16
 	ThrottleTime time.Duration
diff --git a/vendor/gopkg.in/Shopify/sarama.v1/acl_types.go b/vendor/gopkg.in/Shopify/sarama.v1/acl_types.go
index 72b7985..c10ad7b 100644
--- a/vendor/gopkg.in/Shopify/sarama.v1/acl_types.go
+++ b/vendor/gopkg.in/Shopify/sarama.v1/acl_types.go
@@ -1,50 +1,51 @@
 package sarama
 
-type AclOperation int
+type (
+	AclOperation int
+
+	AclPermissionType int
+
+	AclResourceType int
+
+	AclResourcePatternType int
+)
 
 // ref: https://github.com/apache/kafka/blob/trunk/clients/src/main/java/org/apache/kafka/common/acl/AclOperation.java
 const (
-	AclOperationUnknown         AclOperation = 0
-	AclOperationAny             AclOperation = 1
-	AclOperationAll             AclOperation = 2
-	AclOperationRead            AclOperation = 3
-	AclOperationWrite           AclOperation = 4
-	AclOperationCreate          AclOperation = 5
-	AclOperationDelete          AclOperation = 6
-	AclOperationAlter           AclOperation = 7
-	AclOperationDescribe        AclOperation = 8
-	AclOperationClusterAction   AclOperation = 9
-	AclOperationDescribeConfigs AclOperation = 10
-	AclOperationAlterConfigs    AclOperation = 11
-	AclOperationIdempotentWrite AclOperation = 12
+	AclOperationUnknown AclOperation = iota
+	AclOperationAny
+	AclOperationAll
+	AclOperationRead
+	AclOperationWrite
+	AclOperationCreate
+	AclOperationDelete
+	AclOperationAlter
+	AclOperationDescribe
+	AclOperationClusterAction
+	AclOperationDescribeConfigs
+	AclOperationAlterConfigs
+	AclOperationIdempotentWrite
 )
 
-type AclPermissionType int
-
 // ref: https://github.com/apache/kafka/blob/trunk/clients/src/main/java/org/apache/kafka/common/acl/AclPermissionType.java
 const (
-	AclPermissionUnknown AclPermissionType = 0
-	AclPermissionAny     AclPermissionType = 1
-	AclPermissionDeny    AclPermissionType = 2
-	AclPermissionAllow   AclPermissionType = 3
+	AclPermissionUnknown AclPermissionType = iota
+	AclPermissionAny
+	AclPermissionDeny
+	AclPermissionAllow
 )
 
-type AclResourceType int
-
 // ref: https://github.com/apache/kafka/blob/trunk/clients/src/main/java/org/apache/kafka/common/resource/ResourceType.java
 const (
-	AclResourceUnknown         AclResourceType = 0
-	AclResourceAny             AclResourceType = 1
-	AclResourceTopic           AclResourceType = 2
-	AclResourceGroup           AclResourceType = 3
-	AclResourceCluster         AclResourceType = 4
-	AclResourceTransactionalID AclResourceType = 5
+	AclResourceUnknown AclResourceType = iota
+	AclResourceAny
+	AclResourceTopic
+	AclResourceGroup
+	AclResourceCluster
+	AclResourceTransactionalID
 )
 
-type AclResourcePatternType int
-
 // ref: https://github.com/apache/kafka/blob/trunk/clients/src/main/java/org/apache/kafka/common/resource/PatternType.java
-
 const (
 	AclPatternUnknown AclResourcePatternType = iota
 	AclPatternAny
diff --git a/vendor/gopkg.in/Shopify/sarama.v1/add_offsets_to_txn_request.go b/vendor/gopkg.in/Shopify/sarama.v1/add_offsets_to_txn_request.go
index 6da166c..fc227ab 100644
--- a/vendor/gopkg.in/Shopify/sarama.v1/add_offsets_to_txn_request.go
+++ b/vendor/gopkg.in/Shopify/sarama.v1/add_offsets_to_txn_request.go
@@ -1,5 +1,6 @@
 package sarama
 
+//AddOffsetsToTxnRequest adds offsets to a transaction request
 type AddOffsetsToTxnRequest struct {
 	TransactionalID string
 	ProducerID      int64
diff --git a/vendor/gopkg.in/Shopify/sarama.v1/add_offsets_to_txn_response.go b/vendor/gopkg.in/Shopify/sarama.v1/add_offsets_to_txn_response.go
index 3a46151..c88c1f8 100644
--- a/vendor/gopkg.in/Shopify/sarama.v1/add_offsets_to_txn_response.go
+++ b/vendor/gopkg.in/Shopify/sarama.v1/add_offsets_to_txn_response.go
@@ -4,6 +4,7 @@
 	"time"
 )
 
+//AddOffsetsToTxnResponse is a response type for adding offsets to txns
 type AddOffsetsToTxnResponse struct {
 	ThrottleTime time.Duration
 	Err          KError
diff --git a/vendor/gopkg.in/Shopify/sarama.v1/add_partitions_to_txn_request.go b/vendor/gopkg.in/Shopify/sarama.v1/add_partitions_to_txn_request.go
index a8a5922..8d4b42e 100644
--- a/vendor/gopkg.in/Shopify/sarama.v1/add_partitions_to_txn_request.go
+++ b/vendor/gopkg.in/Shopify/sarama.v1/add_partitions_to_txn_request.go
@@ -1,5 +1,6 @@
 package sarama
 
+//AddPartitionsToTxnRequest is a add paartition request
 type AddPartitionsToTxnRequest struct {
 	TransactionalID string
 	ProducerID      int64
diff --git a/vendor/gopkg.in/Shopify/sarama.v1/add_partitions_to_txn_response.go b/vendor/gopkg.in/Shopify/sarama.v1/add_partitions_to_txn_response.go
index 581c556..eb4f23e 100644
--- a/vendor/gopkg.in/Shopify/sarama.v1/add_partitions_to_txn_response.go
+++ b/vendor/gopkg.in/Shopify/sarama.v1/add_partitions_to_txn_response.go
@@ -4,6 +4,7 @@
 	"time"
 )
 
+//AddPartitionsToTxnResponse is a partition errors to transaction type
 type AddPartitionsToTxnResponse struct {
 	ThrottleTime time.Duration
 	Errors       map[string][]*PartitionError
@@ -82,6 +83,7 @@
 	return V0_11_0_0
 }
 
+//PartitionError is a partition error type
 type PartitionError struct {
 	Partition int32
 	Err       KError
diff --git a/vendor/gopkg.in/Shopify/sarama.v1/admin.go b/vendor/gopkg.in/Shopify/sarama.v1/admin.go
index 18b055a..a4d1bc5 100644
--- a/vendor/gopkg.in/Shopify/sarama.v1/admin.go
+++ b/vendor/gopkg.in/Shopify/sarama.v1/admin.go
@@ -20,7 +20,7 @@
 	// List the topics available in the cluster with the default options.
 	ListTopics() (map[string]TopicDetail, error)
 
-	// Describe some topics in the cluster
+	// Describe some topics in the cluster.
 	DescribeTopics(topics []string) (metadata []*TopicMetadata, err error)
 
 	// Delete a topic. It may take several seconds after the DeleteTopic to returns success
@@ -78,12 +78,15 @@
 	// List the consumer groups available in the cluster.
 	ListConsumerGroups() (map[string]string, error)
 
-	// Describe the given consumer group
+	// Describe the given consumer groups.
 	DescribeConsumerGroups(groups []string) ([]*GroupDescription, error)
 
 	// List the consumer group offsets available in the cluster.
 	ListConsumerGroupOffsets(group string, topicPartitions map[string][]int32) (*OffsetFetchResponse, error)
 
+	// Delete a consumer group.
+	DeleteConsumerGroup(group string) error
+
 	// Get information about the nodes in the cluster
 	DescribeCluster() (brokers []*Broker, controllerID int32, err error)
 
@@ -131,7 +134,7 @@
 	}
 
 	if detail == nil {
-		return errors.New("You must specify topic details")
+		return errors.New("you must specify topic details")
 	}
 
 	topicDetails := make(map[string]*TopicDetail)
@@ -166,7 +169,7 @@
 	}
 
 	if topicErr.Err != ErrNoError {
-		return topicErr.Err
+		return topicErr
 	}
 
 	return nil
@@ -183,7 +186,9 @@
 		AllowAutoTopicCreation: false,
 	}
 
-	if ca.conf.Version.IsAtLeast(V0_11_0_0) {
+	if ca.conf.Version.IsAtLeast(V1_0_0_0) {
+		request.Version = 5
+	} else if ca.conf.Version.IsAtLeast(V0_11_0_0) {
 		request.Version = 4
 	}
 
@@ -358,7 +363,7 @@
 	}
 
 	if topicErr.Err != ErrNoError {
-		return topicErr.Err
+		return topicErr
 	}
 
 	return nil
@@ -606,9 +611,38 @@
 		partitions:    topicPartitions,
 	}
 
-	if ca.conf.Version.IsAtLeast(V0_8_2_2) {
+	if ca.conf.Version.IsAtLeast(V0_10_2_0) {
+		request.Version = 2
+	} else if ca.conf.Version.IsAtLeast(V0_8_2_2) {
 		request.Version = 1
 	}
 
 	return coordinator.FetchOffset(request)
 }
+
+func (ca *clusterAdmin) DeleteConsumerGroup(group string) error {
+	coordinator, err := ca.client.Coordinator(group)
+	if err != nil {
+		return err
+	}
+
+	request := &DeleteGroupsRequest{
+		Groups: []string{group},
+	}
+
+	resp, err := coordinator.DeleteGroups(request)
+	if err != nil {
+		return err
+	}
+
+	groupErr, ok := resp.GroupErrorCodes[group]
+	if !ok {
+		return ErrIncompleteResponse
+	}
+
+	if groupErr != ErrNoError {
+		return groupErr
+	}
+
+	return nil
+}
diff --git a/vendor/gopkg.in/Shopify/sarama.v1/alter_configs_request.go b/vendor/gopkg.in/Shopify/sarama.v1/alter_configs_request.go
index 48c44ea..26c275b 100644
--- a/vendor/gopkg.in/Shopify/sarama.v1/alter_configs_request.go
+++ b/vendor/gopkg.in/Shopify/sarama.v1/alter_configs_request.go
@@ -1,45 +1,47 @@
 package sarama
 
+//AlterConfigsRequest is an alter config request type
 type AlterConfigsRequest struct {
 	Resources    []*AlterConfigsResource
 	ValidateOnly bool
 }
 
+//AlterConfigsResource is an alter config resource type
 type AlterConfigsResource struct {
 	Type          ConfigResourceType
 	Name          string
 	ConfigEntries map[string]*string
 }
 
-func (acr *AlterConfigsRequest) encode(pe packetEncoder) error {
-	if err := pe.putArrayLength(len(acr.Resources)); err != nil {
+func (a *AlterConfigsRequest) encode(pe packetEncoder) error {
+	if err := pe.putArrayLength(len(a.Resources)); err != nil {
 		return err
 	}
 
-	for _, r := range acr.Resources {
+	for _, r := range a.Resources {
 		if err := r.encode(pe); err != nil {
 			return err
 		}
 	}
 
-	pe.putBool(acr.ValidateOnly)
+	pe.putBool(a.ValidateOnly)
 	return nil
 }
 
-func (acr *AlterConfigsRequest) decode(pd packetDecoder, version int16) error {
+func (a *AlterConfigsRequest) decode(pd packetDecoder, version int16) error {
 	resourceCount, err := pd.getArrayLength()
 	if err != nil {
 		return err
 	}
 
-	acr.Resources = make([]*AlterConfigsResource, resourceCount)
-	for i := range acr.Resources {
+	a.Resources = make([]*AlterConfigsResource, resourceCount)
+	for i := range a.Resources {
 		r := &AlterConfigsResource{}
 		err = r.decode(pd, version)
 		if err != nil {
 			return err
 		}
-		acr.Resources[i] = r
+		a.Resources[i] = r
 	}
 
 	validateOnly, err := pd.getBool()
@@ -47,22 +49,22 @@
 		return err
 	}
 
-	acr.ValidateOnly = validateOnly
+	a.ValidateOnly = validateOnly
 
 	return nil
 }
 
-func (ac *AlterConfigsResource) encode(pe packetEncoder) error {
-	pe.putInt8(int8(ac.Type))
+func (a *AlterConfigsResource) encode(pe packetEncoder) error {
+	pe.putInt8(int8(a.Type))
 
-	if err := pe.putString(ac.Name); err != nil {
+	if err := pe.putString(a.Name); err != nil {
 		return err
 	}
 
-	if err := pe.putArrayLength(len(ac.ConfigEntries)); err != nil {
+	if err := pe.putArrayLength(len(a.ConfigEntries)); err != nil {
 		return err
 	}
-	for configKey, configValue := range ac.ConfigEntries {
+	for configKey, configValue := range a.ConfigEntries {
 		if err := pe.putString(configKey); err != nil {
 			return err
 		}
@@ -74,18 +76,18 @@
 	return nil
 }
 
-func (ac *AlterConfigsResource) decode(pd packetDecoder, version int16) error {
+func (a *AlterConfigsResource) decode(pd packetDecoder, version int16) error {
 	t, err := pd.getInt8()
 	if err != nil {
 		return err
 	}
-	ac.Type = ConfigResourceType(t)
+	a.Type = ConfigResourceType(t)
 
 	name, err := pd.getString()
 	if err != nil {
 		return err
 	}
-	ac.Name = name
+	a.Name = name
 
 	n, err := pd.getArrayLength()
 	if err != nil {
@@ -93,13 +95,13 @@
 	}
 
 	if n > 0 {
-		ac.ConfigEntries = make(map[string]*string, n)
+		a.ConfigEntries = make(map[string]*string, n)
 		for i := 0; i < n; i++ {
 			configKey, err := pd.getString()
 			if err != nil {
 				return err
 			}
-			if ac.ConfigEntries[configKey], err = pd.getNullableString(); err != nil {
+			if a.ConfigEntries[configKey], err = pd.getNullableString(); err != nil {
 				return err
 			}
 		}
@@ -107,14 +109,14 @@
 	return err
 }
 
-func (acr *AlterConfigsRequest) key() int16 {
+func (a *AlterConfigsRequest) key() int16 {
 	return 33
 }
 
-func (acr *AlterConfigsRequest) version() int16 {
+func (a *AlterConfigsRequest) version() int16 {
 	return 0
 }
 
-func (acr *AlterConfigsRequest) requiredVersion() KafkaVersion {
+func (a *AlterConfigsRequest) requiredVersion() KafkaVersion {
 	return V0_11_0_0
 }
diff --git a/vendor/gopkg.in/Shopify/sarama.v1/alter_configs_response.go b/vendor/gopkg.in/Shopify/sarama.v1/alter_configs_response.go
index 29b09e1..3893663 100644
--- a/vendor/gopkg.in/Shopify/sarama.v1/alter_configs_response.go
+++ b/vendor/gopkg.in/Shopify/sarama.v1/alter_configs_response.go
@@ -2,11 +2,13 @@
 
 import "time"
 
+//AlterConfigsResponse is a reponse type for alter config
 type AlterConfigsResponse struct {
 	ThrottleTime time.Duration
 	Resources    []*AlterConfigsResourceResponse
 }
 
+//AlterConfigsResourceResponse is a reponse type for alter config resource
 type AlterConfigsResourceResponse struct {
 	ErrorCode int16
 	ErrorMsg  string
@@ -14,21 +16,21 @@
 	Name      string
 }
 
-func (ct *AlterConfigsResponse) encode(pe packetEncoder) error {
-	pe.putInt32(int32(ct.ThrottleTime / time.Millisecond))
+func (a *AlterConfigsResponse) encode(pe packetEncoder) error {
+	pe.putInt32(int32(a.ThrottleTime / time.Millisecond))
 
-	if err := pe.putArrayLength(len(ct.Resources)); err != nil {
+	if err := pe.putArrayLength(len(a.Resources)); err != nil {
 		return err
 	}
 
-	for i := range ct.Resources {
-		pe.putInt16(ct.Resources[i].ErrorCode)
-		err := pe.putString(ct.Resources[i].ErrorMsg)
+	for i := range a.Resources {
+		pe.putInt16(a.Resources[i].ErrorCode)
+		err := pe.putString(a.Resources[i].ErrorMsg)
 		if err != nil {
 			return nil
 		}
-		pe.putInt8(int8(ct.Resources[i].Type))
-		err = pe.putString(ct.Resources[i].Name)
+		pe.putInt8(int8(a.Resources[i].Type))
+		err = pe.putString(a.Resources[i].Name)
 		if err != nil {
 			return nil
 		}
@@ -37,59 +39,59 @@
 	return nil
 }
 
-func (acr *AlterConfigsResponse) decode(pd packetDecoder, version int16) error {
+func (a *AlterConfigsResponse) decode(pd packetDecoder, version int16) error {
 	throttleTime, err := pd.getInt32()
 	if err != nil {
 		return err
 	}
-	acr.ThrottleTime = time.Duration(throttleTime) * time.Millisecond
+	a.ThrottleTime = time.Duration(throttleTime) * time.Millisecond
 
 	responseCount, err := pd.getArrayLength()
 	if err != nil {
 		return err
 	}
 
-	acr.Resources = make([]*AlterConfigsResourceResponse, responseCount)
+	a.Resources = make([]*AlterConfigsResourceResponse, responseCount)
 
-	for i := range acr.Resources {
-		acr.Resources[i] = new(AlterConfigsResourceResponse)
+	for i := range a.Resources {
+		a.Resources[i] = new(AlterConfigsResourceResponse)
 
 		errCode, err := pd.getInt16()
 		if err != nil {
 			return err
 		}
-		acr.Resources[i].ErrorCode = errCode
+		a.Resources[i].ErrorCode = errCode
 
 		e, err := pd.getString()
 		if err != nil {
 			return err
 		}
-		acr.Resources[i].ErrorMsg = e
+		a.Resources[i].ErrorMsg = e
 
 		t, err := pd.getInt8()
 		if err != nil {
 			return err
 		}
-		acr.Resources[i].Type = ConfigResourceType(t)
+		a.Resources[i].Type = ConfigResourceType(t)
 
 		name, err := pd.getString()
 		if err != nil {
 			return err
 		}
-		acr.Resources[i].Name = name
+		a.Resources[i].Name = name
 	}
 
 	return nil
 }
 
-func (r *AlterConfigsResponse) key() int16 {
+func (a *AlterConfigsResponse) key() int16 {
 	return 32
 }
 
-func (r *AlterConfigsResponse) version() int16 {
+func (a *AlterConfigsResponse) version() int16 {
 	return 0
 }
 
-func (r *AlterConfigsResponse) requiredVersion() KafkaVersion {
+func (a *AlterConfigsResponse) requiredVersion() KafkaVersion {
 	return V0_11_0_0
 }
diff --git a/vendor/gopkg.in/Shopify/sarama.v1/api_versions_request.go b/vendor/gopkg.in/Shopify/sarama.v1/api_versions_request.go
index ab65f01..b33167c 100644
--- a/vendor/gopkg.in/Shopify/sarama.v1/api_versions_request.go
+++ b/vendor/gopkg.in/Shopify/sarama.v1/api_versions_request.go
@@ -1,24 +1,25 @@
 package sarama
 
+//ApiVersionsRequest ...
 type ApiVersionsRequest struct {
 }
 
-func (r *ApiVersionsRequest) encode(pe packetEncoder) error {
+func (a *ApiVersionsRequest) encode(pe packetEncoder) error {
 	return nil
 }
 
-func (r *ApiVersionsRequest) decode(pd packetDecoder, version int16) (err error) {
+func (a *ApiVersionsRequest) decode(pd packetDecoder, version int16) (err error) {
 	return nil
 }
 
-func (r *ApiVersionsRequest) key() int16 {
+func (a *ApiVersionsRequest) key() int16 {
 	return 18
 }
 
-func (r *ApiVersionsRequest) version() int16 {
+func (a *ApiVersionsRequest) version() int16 {
 	return 0
 }
 
-func (r *ApiVersionsRequest) requiredVersion() KafkaVersion {
+func (a *ApiVersionsRequest) requiredVersion() KafkaVersion {
 	return V0_10_0_0
 }
diff --git a/vendor/gopkg.in/Shopify/sarama.v1/api_versions_response.go b/vendor/gopkg.in/Shopify/sarama.v1/api_versions_response.go
index 23bc326..bb1f0b3 100644
--- a/vendor/gopkg.in/Shopify/sarama.v1/api_versions_response.go
+++ b/vendor/gopkg.in/Shopify/sarama.v1/api_versions_response.go
@@ -1,5 +1,6 @@
 package sarama
 
+//ApiVersionsResponseBlock is an api version reponse block type
 type ApiVersionsResponseBlock struct {
 	ApiKey     int16
 	MinVersion int16
@@ -31,6 +32,7 @@
 	return nil
 }
 
+//ApiVersionsResponse is an api version response type
 type ApiVersionsResponse struct {
 	Err         KError
 	ApiVersions []*ApiVersionsResponseBlock
diff --git a/vendor/gopkg.in/Shopify/sarama.v1/async_producer.go b/vendor/gopkg.in/Shopify/sarama.v1/async_producer.go
index 5174a35..11e0849 100644
--- a/vendor/gopkg.in/Shopify/sarama.v1/async_producer.go
+++ b/vendor/gopkg.in/Shopify/sarama.v1/async_producer.go
@@ -92,9 +92,8 @@
 }
 
 type asyncProducer struct {
-	client    Client
-	conf      *Config
-	ownClient bool
+	client Client
+	conf   *Config
 
 	errors                    chan *ProducerError
 	input, successes, retries chan *ProducerMessage
@@ -113,18 +112,19 @@
 	if err != nil {
 		return nil, err
 	}
-
-	p, err := NewAsyncProducerFromClient(client)
-	if err != nil {
-		return nil, err
-	}
-	p.(*asyncProducer).ownClient = true
-	return p, nil
+	return newAsyncProducer(client)
 }
 
 // NewAsyncProducerFromClient creates a new Producer using the given client. It is still
 // necessary to call Close() on the underlying client when shutting down this producer.
 func NewAsyncProducerFromClient(client Client) (AsyncProducer, error) {
+	// For clients passed in by the client, ensure we don't
+	// call Close() on it.
+	cli := &nopCloserClient{client}
+	return newAsyncProducer(cli)
+}
+
+func newAsyncProducer(client Client) (AsyncProducer, error) {
 	// Check that we are not dealing with a closed Client before processing any other arguments
 	if client.Closed() {
 		return nil, ErrClosedClient
@@ -191,10 +191,17 @@
 	// Partition is the partition that the message was sent to. This is only
 	// guaranteed to be defined if the message was successfully delivered.
 	Partition int32
-	// Timestamp is the timestamp assigned to the message by the broker. This
-	// is only guaranteed to be defined if the message was successfully
-	// delivered, RequiredAcks is not NoResponse, and the Kafka broker is at
-	// least version 0.10.0.
+	// Timestamp can vary in behaviour depending on broker configuration, being
+	// in either one of the CreateTime or LogAppendTime modes (default CreateTime),
+	// and requiring version at least 0.10.0.
+	//
+	// When configured to CreateTime, the timestamp is specified by the producer
+	// either by explicitly setting this field, or when the message is added
+	// to a produce set.
+	//
+	// When configured to LogAppendTime, the timestamp assigned to the message
+	// by the broker. This is only guaranteed to be defined if the message was
+	// successfully delivered and RequiredAcks is not NoResponse.
 	Timestamp time.Time
 
 	retries        int
@@ -999,11 +1006,9 @@
 
 	p.inFlight.Wait()
 
-	if p.ownClient {
-		err := p.client.Close()
-		if err != nil {
-			Logger.Println("producer/shutdown failed to close the embedded client:", err)
-		}
+	err := p.client.Close()
+	if err != nil {
+		Logger.Println("producer/shutdown failed to close the embedded client:", err)
 	}
 
 	close(p.input)
diff --git a/vendor/gopkg.in/Shopify/sarama.v1/balance_strategy.go b/vendor/gopkg.in/Shopify/sarama.v1/balance_strategy.go
index e78988d..2fce17f 100644
--- a/vendor/gopkg.in/Shopify/sarama.v1/balance_strategy.go
+++ b/vendor/gopkg.in/Shopify/sarama.v1/balance_strategy.go
@@ -24,7 +24,7 @@
 // --------------------------------------------------------------------
 
 // BalanceStrategy is used to balance topics and partitions
-// across memebers of a consumer group
+// across members of a consumer group
 type BalanceStrategy interface {
 	// Name uniquely identifies the strategy.
 	Name() string
@@ -78,7 +78,7 @@
 // Name implements BalanceStrategy.
 func (s *balanceStrategy) Name() string { return s.name }
 
-// Balance implements BalanceStrategy.
+// Plan implements BalanceStrategy.
 func (s *balanceStrategy) Plan(members map[string]ConsumerGroupMemberMetadata, topics map[string][]int32) (BalanceStrategyPlan, error) {
 	// Build members by topic map
 	mbt := make(map[string][]string)
diff --git a/vendor/gopkg.in/Shopify/sarama.v1/broker.go b/vendor/gopkg.in/Shopify/sarama.v1/broker.go
index 9129089..7b32a03 100644
--- a/vendor/gopkg.in/Shopify/sarama.v1/broker.go
+++ b/vendor/gopkg.in/Shopify/sarama.v1/broker.go
@@ -13,24 +13,25 @@
 	"sync/atomic"
 	"time"
 
-	"github.com/rcrowley/go-metrics"
+	metrics "github.com/rcrowley/go-metrics"
 )
 
 // Broker represents a single Kafka broker connection. All operations on this object are entirely concurrency-safe.
 type Broker struct {
-	id   int32
-	addr string
+	conf *Config
 	rack *string
 
-	conf          *Config
+	id            int32
+	addr          string
 	correlationID int32
 	conn          net.Conn
 	connErr       error
 	lock          sync.Mutex
 	opened        int32
+	responses     chan responsePromise
+	done          chan bool
 
-	responses chan responsePromise
-	done      chan bool
+	registeredMetrics []string
 
 	incomingByteRate       metrics.Meter
 	requestRate            metrics.Meter
@@ -46,6 +47,8 @@
 	brokerOutgoingByteRate metrics.Meter
 	brokerResponseRate     metrics.Meter
 	brokerResponseSize     metrics.Histogram
+
+	kerberosAuthenticator GSSAPIKerberosAuth
 }
 
 // SASLMechanism specifies the SASL mechanism the client uses to authenticate with the broker
@@ -56,6 +59,11 @@
 	SASLTypeOAuth = "OAUTHBEARER"
 	// SASLTypePlaintext represents the SASL/PLAIN mechanism
 	SASLTypePlaintext = "PLAIN"
+	// SASLTypeSCRAMSHA256 represents the SCRAM-SHA-256 mechanism.
+	SASLTypeSCRAMSHA256 = "SCRAM-SHA-256"
+	// SASLTypeSCRAMSHA512 represents the SCRAM-SHA-512 mechanism.
+	SASLTypeSCRAMSHA512 = "SCRAM-SHA-512"
+	SASLTypeGSSAPI      = "GSSAPI"
 	// SASLHandshakeV0 is v0 of the Kafka SASL handshake protocol. Client and
 	// server negotiate SASL auth using opaque packets.
 	SASLHandshakeV0 = int16(0)
@@ -92,6 +100,20 @@
 	Token() (*AccessToken, error)
 }
 
+// SCRAMClient is a an interface to a SCRAM
+// client implementation.
+type SCRAMClient interface {
+	// Begin prepares the client for the SCRAM exchange
+	// with the server with a user name and a password
+	Begin(userName, password, authzID string) error
+	// Step steps client through the SCRAM exchange. It is
+	// called repeatedly until it errors or `Done` returns true.
+	Step(challenge string) (response string, err error)
+	// Done should return true when the SCRAM conversation
+	// is over.
+	Done() bool
+}
+
 type responsePromise struct {
 	requestTime   time.Time
 	correlationID int32
@@ -137,6 +159,8 @@
 
 		if conf.Net.TLS.Enable {
 			b.conn, b.connErr = tls.DialWithDialer(&dialer, "tcp", b.addr, conf.Net.TLS.Config)
+		} else if conf.Net.Proxy.Enable {
+			b.conn, b.connErr = conf.Net.Proxy.Dialer.Dial("tcp", b.addr)
 		} else {
 			b.conn, b.connErr = dialer.Dial("tcp", b.addr)
 		}
@@ -161,13 +185,7 @@
 		// Do not gather metrics for seeded broker (only used during bootstrap) because they share
 		// the same id (-1) and are already exposed through the global metrics above
 		if b.id >= 0 {
-			b.brokerIncomingByteRate = getOrRegisterBrokerMeter("incoming-byte-rate", b, conf.MetricRegistry)
-			b.brokerRequestRate = getOrRegisterBrokerMeter("request-rate", b, conf.MetricRegistry)
-			b.brokerRequestSize = getOrRegisterBrokerHistogram("request-size", b, conf.MetricRegistry)
-			b.brokerRequestLatency = getOrRegisterBrokerHistogram("request-latency-in-ms", b, conf.MetricRegistry)
-			b.brokerOutgoingByteRate = getOrRegisterBrokerMeter("outgoing-byte-rate", b, conf.MetricRegistry)
-			b.brokerResponseRate = getOrRegisterBrokerMeter("response-rate", b, conf.MetricRegistry)
-			b.brokerResponseSize = getOrRegisterBrokerHistogram("response-size", b, conf.MetricRegistry)
+			b.registerMetrics()
 		}
 
 		if conf.Net.SASL.Enable {
@@ -210,6 +228,7 @@
 	return b.conn != nil, b.connErr
 }
 
+//Close closes the broker resources
 func (b *Broker) Close() error {
 	b.lock.Lock()
 	defer b.lock.Unlock()
@@ -228,12 +247,7 @@
 	b.done = nil
 	b.responses = nil
 
-	if b.id >= 0 {
-		b.conf.MetricRegistry.Unregister(getMetricNameForBroker("incoming-byte-rate", b))
-		b.conf.MetricRegistry.Unregister(getMetricNameForBroker("request-rate", b))
-		b.conf.MetricRegistry.Unregister(getMetricNameForBroker("outgoing-byte-rate", b))
-		b.conf.MetricRegistry.Unregister(getMetricNameForBroker("response-rate", b))
-	}
+	b.unregisterMetrics()
 
 	if err == nil {
 		Logger.Printf("Closed connection to broker %s\n", b.addr)
@@ -267,6 +281,7 @@
 	return *b.rack
 }
 
+//GetMetadata send a metadata request and returns a metadata response or error
 func (b *Broker) GetMetadata(request *MetadataRequest) (*MetadataResponse, error) {
 	response := new(MetadataResponse)
 
@@ -279,6 +294,7 @@
 	return response, nil
 }
 
+//GetConsumerMetadata send a consumer metadata request and returns a consumer metadata response or error
 func (b *Broker) GetConsumerMetadata(request *ConsumerMetadataRequest) (*ConsumerMetadataResponse, error) {
 	response := new(ConsumerMetadataResponse)
 
@@ -291,6 +307,7 @@
 	return response, nil
 }
 
+//FindCoordinator sends a find coordinate request and returns a response or error
 func (b *Broker) FindCoordinator(request *FindCoordinatorRequest) (*FindCoordinatorResponse, error) {
 	response := new(FindCoordinatorResponse)
 
@@ -303,6 +320,7 @@
 	return response, nil
 }
 
+//GetAvailableOffsets return an offset response or error
 func (b *Broker) GetAvailableOffsets(request *OffsetRequest) (*OffsetResponse, error) {
 	response := new(OffsetResponse)
 
@@ -315,9 +333,12 @@
 	return response, nil
 }
 
+//Produce returns a produce response or error
 func (b *Broker) Produce(request *ProduceRequest) (*ProduceResponse, error) {
-	var response *ProduceResponse
-	var err error
+	var (
+		response *ProduceResponse
+		err      error
+	)
 
 	if request.RequiredAcks == NoResponse {
 		err = b.sendAndReceive(request, nil)
@@ -333,11 +354,11 @@
 	return response, nil
 }
 
+//Fetch returns a FetchResponse or error
 func (b *Broker) Fetch(request *FetchRequest) (*FetchResponse, error) {
 	response := new(FetchResponse)
 
 	err := b.sendAndReceive(request, response)
-
 	if err != nil {
 		return nil, err
 	}
@@ -345,11 +366,11 @@
 	return response, nil
 }
 
+//CommitOffset return an Offset commit reponse or error
 func (b *Broker) CommitOffset(request *OffsetCommitRequest) (*OffsetCommitResponse, error) {
 	response := new(OffsetCommitResponse)
 
 	err := b.sendAndReceive(request, response)
-
 	if err != nil {
 		return nil, err
 	}
@@ -357,11 +378,11 @@
 	return response, nil
 }
 
+//FetchOffset returns an offset fetch response or error
 func (b *Broker) FetchOffset(request *OffsetFetchRequest) (*OffsetFetchResponse, error) {
 	response := new(OffsetFetchResponse)
 
 	err := b.sendAndReceive(request, response)
-
 	if err != nil {
 		return nil, err
 	}
@@ -369,6 +390,7 @@
 	return response, nil
 }
 
+//JoinGroup returns a join group response or error
 func (b *Broker) JoinGroup(request *JoinGroupRequest) (*JoinGroupResponse, error) {
 	response := new(JoinGroupResponse)
 
@@ -380,6 +402,7 @@
 	return response, nil
 }
 
+//SyncGroup returns a sync group response or error
 func (b *Broker) SyncGroup(request *SyncGroupRequest) (*SyncGroupResponse, error) {
 	response := new(SyncGroupResponse)
 
@@ -391,6 +414,7 @@
 	return response, nil
 }
 
+//LeaveGroup return a leave group response or error
 func (b *Broker) LeaveGroup(request *LeaveGroupRequest) (*LeaveGroupResponse, error) {
 	response := new(LeaveGroupResponse)
 
@@ -402,6 +426,7 @@
 	return response, nil
 }
 
+//Heartbeat returns a heartbeat response or error
 func (b *Broker) Heartbeat(request *HeartbeatRequest) (*HeartbeatResponse, error) {
 	response := new(HeartbeatResponse)
 
@@ -413,6 +438,7 @@
 	return response, nil
 }
 
+//ListGroups return a list group response or error
 func (b *Broker) ListGroups(request *ListGroupsRequest) (*ListGroupsResponse, error) {
 	response := new(ListGroupsResponse)
 
@@ -424,6 +450,7 @@
 	return response, nil
 }
 
+//DescribeGroups return describe group response or error
 func (b *Broker) DescribeGroups(request *DescribeGroupsRequest) (*DescribeGroupsResponse, error) {
 	response := new(DescribeGroupsResponse)
 
@@ -435,6 +462,7 @@
 	return response, nil
 }
 
+//ApiVersions return api version response or error
 func (b *Broker) ApiVersions(request *ApiVersionsRequest) (*ApiVersionsResponse, error) {
 	response := new(ApiVersionsResponse)
 
@@ -446,6 +474,7 @@
 	return response, nil
 }
 
+//CreateTopics send a create topic request and returns create topic response
 func (b *Broker) CreateTopics(request *CreateTopicsRequest) (*CreateTopicsResponse, error) {
 	response := new(CreateTopicsResponse)
 
@@ -457,6 +486,7 @@
 	return response, nil
 }
 
+//DeleteTopics sends a delete topic request and returns delete topic response
 func (b *Broker) DeleteTopics(request *DeleteTopicsRequest) (*DeleteTopicsResponse, error) {
 	response := new(DeleteTopicsResponse)
 
@@ -468,6 +498,8 @@
 	return response, nil
 }
 
+//CreatePartitions sends a create partition request and returns create
+//partitions response or error
 func (b *Broker) CreatePartitions(request *CreatePartitionsRequest) (*CreatePartitionsResponse, error) {
 	response := new(CreatePartitionsResponse)
 
@@ -479,6 +511,8 @@
 	return response, nil
 }
 
+//DeleteRecords send a request to delete records and return delete record
+//response or error
 func (b *Broker) DeleteRecords(request *DeleteRecordsRequest) (*DeleteRecordsResponse, error) {
 	response := new(DeleteRecordsResponse)
 
@@ -490,6 +524,7 @@
 	return response, nil
 }
 
+//DescribeAcls sends a describe acl request and returns a response or error
 func (b *Broker) DescribeAcls(request *DescribeAclsRequest) (*DescribeAclsResponse, error) {
 	response := new(DescribeAclsResponse)
 
@@ -501,6 +536,7 @@
 	return response, nil
 }
 
+//CreateAcls sends a create acl request and returns a response or error
 func (b *Broker) CreateAcls(request *CreateAclsRequest) (*CreateAclsResponse, error) {
 	response := new(CreateAclsResponse)
 
@@ -512,6 +548,7 @@
 	return response, nil
 }
 
+//DeleteAcls sends a delete acl request and returns a response or error
 func (b *Broker) DeleteAcls(request *DeleteAclsRequest) (*DeleteAclsResponse, error) {
 	response := new(DeleteAclsResponse)
 
@@ -523,6 +560,7 @@
 	return response, nil
 }
 
+//InitProducerID sends an init producer request and returns a response or error
 func (b *Broker) InitProducerID(request *InitProducerIDRequest) (*InitProducerIDResponse, error) {
 	response := new(InitProducerIDResponse)
 
@@ -534,6 +572,8 @@
 	return response, nil
 }
 
+//AddPartitionsToTxn send a request to add partition to txn and returns
+//a response or error
 func (b *Broker) AddPartitionsToTxn(request *AddPartitionsToTxnRequest) (*AddPartitionsToTxnResponse, error) {
 	response := new(AddPartitionsToTxnResponse)
 
@@ -545,6 +585,8 @@
 	return response, nil
 }
 
+//AddOffsetsToTxn sends a request to add offsets to txn and returns a response
+//or error
 func (b *Broker) AddOffsetsToTxn(request *AddOffsetsToTxnRequest) (*AddOffsetsToTxnResponse, error) {
 	response := new(AddOffsetsToTxnResponse)
 
@@ -556,6 +598,7 @@
 	return response, nil
 }
 
+//EndTxn sends a request to end txn and returns a response or error
 func (b *Broker) EndTxn(request *EndTxnRequest) (*EndTxnResponse, error) {
 	response := new(EndTxnResponse)
 
@@ -567,6 +610,8 @@
 	return response, nil
 }
 
+//TxnOffsetCommit sends a request to commit transaction offsets and returns
+//a response or error
 func (b *Broker) TxnOffsetCommit(request *TxnOffsetCommitRequest) (*TxnOffsetCommitResponse, error) {
 	response := new(TxnOffsetCommitResponse)
 
@@ -578,6 +623,8 @@
 	return response, nil
 }
 
+//DescribeConfigs sends a request to describe config and returns a response or
+//error
 func (b *Broker) DescribeConfigs(request *DescribeConfigsRequest) (*DescribeConfigsResponse, error) {
 	response := new(DescribeConfigsResponse)
 
@@ -589,6 +636,7 @@
 	return response, nil
 }
 
+//AlterConfigs sends a request to alter config and return a response or error
 func (b *Broker) AlterConfigs(request *AlterConfigsRequest) (*AlterConfigsResponse, error) {
 	response := new(AlterConfigsResponse)
 
@@ -600,6 +648,7 @@
 	return response, nil
 }
 
+//DeleteGroups sends a request to delete groups and returns a response or error
 func (b *Broker) DeleteGroups(request *DeleteGroupsRequest) (*DeleteGroupsResponse, error) {
 	response := new(DeleteGroupsResponse)
 
@@ -638,7 +687,7 @@
 
 	requestTime := time.Now()
 	bytes, err := b.conn.Write(buf)
-	b.updateOutgoingCommunicationMetrics(bytes)
+	b.updateOutgoingCommunicationMetrics(bytes) //TODO: should it be after error check
 	if err != nil {
 		return nil, err
 	}
@@ -658,7 +707,6 @@
 
 func (b *Broker) sendAndReceive(req protocolBody, res versionedDecoder) error {
 	promise, err := b.send(req, res != nil)
-
 	if err != nil {
 		return err
 	}
@@ -707,11 +755,11 @@
 }
 
 func (b *Broker) encode(pe packetEncoder, version int16) (err error) {
-
 	host, portstr, err := net.SplitHostPort(b.addr)
 	if err != nil {
 		return err
 	}
+
 	port, err := strconv.Atoi(portstr)
 	if err != nil {
 		return err
@@ -739,6 +787,7 @@
 func (b *Broker) responseReceiver() {
 	var dead error
 	header := make([]byte, 8)
+
 	for response := range b.responses {
 		if dead != nil {
 			response.errors <- dead
@@ -793,14 +842,28 @@
 }
 
 func (b *Broker) authenticateViaSASL() error {
-	if b.conf.Net.SASL.Mechanism == SASLTypeOAuth {
+	switch b.conf.Net.SASL.Mechanism {
+	case SASLTypeOAuth:
 		return b.sendAndReceiveSASLOAuth(b.conf.Net.SASL.TokenProvider)
+	case SASLTypeSCRAMSHA256, SASLTypeSCRAMSHA512:
+		return b.sendAndReceiveSASLSCRAMv1()
+	case SASLTypeGSSAPI:
+		return b.sendAndReceiveKerberos()
+	default:
+		return b.sendAndReceiveSASLPlainAuth()
 	}
-	return b.sendAndReceiveSASLPlainAuth()
 }
 
-func (b *Broker) sendAndReceiveSASLHandshake(saslType string, version int16) error {
-	rb := &SaslHandshakeRequest{Mechanism: saslType, Version: version}
+func (b *Broker) sendAndReceiveKerberos() error {
+	b.kerberosAuthenticator.Config = &b.conf.Net.SASL.GSSAPI
+	if b.kerberosAuthenticator.NewKerberosClientFunc == nil {
+		b.kerberosAuthenticator.NewKerberosClientFunc = NewKerberosClient
+	}
+	return b.kerberosAuthenticator.Authorize(b)
+}
+
+func (b *Broker) sendAndReceiveSASLHandshake(saslType SASLMechanism, version int16) error {
+	rb := &SaslHandshakeRequest{Mechanism: string(saslType), Version: version}
 
 	req := &request{correlationID: b.correlationID, clientID: b.conf.ClientID, body: rb}
 	buf, err := encode(req, b.conf.MetricRegistry)
@@ -828,6 +891,7 @@
 		Logger.Printf("Failed to read SASL handshake header : %s\n", err.Error())
 		return err
 	}
+
 	length := binary.BigEndian.Uint32(header[:4])
 	payload := make([]byte, length-4)
 	n, err := io.ReadFull(b.conn, payload)
@@ -835,23 +899,29 @@
 		Logger.Printf("Failed to read SASL handshake payload : %s\n", err.Error())
 		return err
 	}
+
 	b.updateIncomingCommunicationMetrics(n+8, time.Since(requestTime))
 	res := &SaslHandshakeResponse{}
+
 	err = versionedDecode(payload, res, 0)
 	if err != nil {
 		Logger.Printf("Failed to parse SASL handshake : %s\n", err.Error())
 		return err
 	}
+
 	if res.Err != ErrNoError {
 		Logger.Printf("Invalid SASL Mechanism : %s\n", res.Err.Error())
 		return res.Err
 	}
-	Logger.Print("Successful SASL handshake")
+
+	Logger.Print("Successful SASL handshake. Available mechanisms: ", res.EnabledMechanisms)
 	return nil
 }
 
-// Kafka 0.10.0 plans to support SASL Plain and Kerberos as per PR #812 (KIP-43)/(JIRA KAFKA-3149)
-// Some hosted kafka services such as IBM Message Hub already offer SASL/PLAIN auth with Kafka 0.9
+// Kafka 0.10.x supported SASL PLAIN/Kerberos via KAFKA-3149 (KIP-43).
+// Kafka 1.x.x onward added a SaslAuthenticate request/response message which
+// wraps the SASL flow in the Kafka protocol, which allows for returning
+// meaningful errors on authentication failure.
 //
 // In SASL Plain, Kafka expects the auth header to be in the following format
 // Message format (from https://tools.ietf.org/html/rfc4616):
@@ -865,17 +935,34 @@
 //   SAFE      = UTF1 / UTF2 / UTF3 / UTF4
 //                  ;; any UTF-8 encoded Unicode character except NUL
 //
+// With SASL v0 handshake and auth then:
 // When credentials are valid, Kafka returns a 4 byte array of null characters.
-// When credentials are invalid, Kafka closes the connection. This does not seem to be the ideal way
-// of responding to bad credentials but thats how its being done today.
+// When credentials are invalid, Kafka closes the connection.
+//
+// With SASL v1 handshake and auth then:
+// When credentials are invalid, Kafka replies with a SaslAuthenticate response
+// containing an error code and message detailing the authentication failure.
 func (b *Broker) sendAndReceiveSASLPlainAuth() error {
+	// default to V0 to allow for backward compatability when SASL is enabled
+	// but not the handshake
 	if b.conf.Net.SASL.Handshake {
-		handshakeErr := b.sendAndReceiveSASLHandshake(SASLTypePlaintext, SASLHandshakeV0)
+
+		handshakeErr := b.sendAndReceiveSASLHandshake(SASLTypePlaintext, b.conf.Net.SASL.Version)
 		if handshakeErr != nil {
 			Logger.Printf("Error while performing SASL handshake %s\n", b.addr)
 			return handshakeErr
 		}
 	}
+
+	if b.conf.Net.SASL.Version == SASLHandshakeV1 {
+		return b.sendAndReceiveV1SASLPlainAuth()
+	}
+	return b.sendAndReceiveV0SASLPlainAuth()
+}
+
+// sendAndReceiveV0SASLPlainAuth flows the v0 sasl auth NOT wrapped in the kafka protocol
+func (b *Broker) sendAndReceiveV0SASLPlainAuth() error {
+
 	length := 1 + len(b.conf.Net.SASL.User) + 1 + len(b.conf.Net.SASL.Password)
 	authBytes := make([]byte, length+4) //4 byte length header + auth data
 	binary.BigEndian.PutUint32(authBytes, uint32(length))
@@ -909,36 +996,59 @@
 	return nil
 }
 
+// sendAndReceiveV1SASLPlainAuth flows the v1 sasl authentication using the kafka protocol
+func (b *Broker) sendAndReceiveV1SASLPlainAuth() error {
+	correlationID := b.correlationID
+
+	requestTime := time.Now()
+
+	bytesWritten, err := b.sendSASLPlainAuthClientResponse(correlationID)
+
+	b.updateOutgoingCommunicationMetrics(bytesWritten)
+
+	if err != nil {
+		Logger.Printf("Failed to write SASL auth header to broker %s: %s\n", b.addr, err.Error())
+		return err
+	}
+
+	b.correlationID++
+
+	bytesRead, err := b.receiveSASLServerResponse(correlationID)
+	b.updateIncomingCommunicationMetrics(bytesRead, time.Since(requestTime))
+
+	// With v1 sasl we get an error message set in the response we can return
+	if err != nil {
+		Logger.Printf("Error returned from broker during SASL flow %s: %s\n", b.addr, err.Error())
+		return err
+	}
+
+	return nil
+}
+
 // sendAndReceiveSASLOAuth performs the authentication flow as described by KIP-255
 // https://cwiki.apache.org/confluence/pages/viewpage.action?pageId=75968876
 func (b *Broker) sendAndReceiveSASLOAuth(provider AccessTokenProvider) error {
-
 	if err := b.sendAndReceiveSASLHandshake(SASLTypeOAuth, SASLHandshakeV1); err != nil {
 		return err
 	}
 
 	token, err := provider.Token()
-
 	if err != nil {
 		return err
 	}
 
 	requestTime := time.Now()
-
 	correlationID := b.correlationID
 
 	bytesWritten, err := b.sendSASLOAuthBearerClientResponse(token, correlationID)
-
 	if err != nil {
 		return err
 	}
 
 	b.updateOutgoingCommunicationMetrics(bytesWritten)
-
 	b.correlationID++
 
-	bytesRead, err := b.receiveSASLOAuthBearerServerResponse(correlationID)
-
+	bytesRead, err := b.receiveSASLServerResponse(correlationID)
 	if err != nil {
 		return err
 	}
@@ -949,15 +1059,107 @@
 	return nil
 }
 
+func (b *Broker) sendAndReceiveSASLSCRAMv1() error {
+	if err := b.sendAndReceiveSASLHandshake(b.conf.Net.SASL.Mechanism, SASLHandshakeV1); err != nil {
+		return err
+	}
+
+	scramClient := b.conf.Net.SASL.SCRAMClientGeneratorFunc()
+	if err := scramClient.Begin(b.conf.Net.SASL.User, b.conf.Net.SASL.Password, b.conf.Net.SASL.SCRAMAuthzID); err != nil {
+		return fmt.Errorf("failed to start SCRAM exchange with the server: %s", err.Error())
+	}
+
+	msg, err := scramClient.Step("")
+	if err != nil {
+		return fmt.Errorf("failed to advance the SCRAM exchange: %s", err.Error())
+
+	}
+
+	for !scramClient.Done() {
+		requestTime := time.Now()
+		correlationID := b.correlationID
+		bytesWritten, err := b.sendSaslAuthenticateRequest(correlationID, []byte(msg))
+		if err != nil {
+			Logger.Printf("Failed to write SASL auth header to broker %s: %s\n", b.addr, err.Error())
+			return err
+		}
+
+		b.updateOutgoingCommunicationMetrics(bytesWritten)
+		b.correlationID++
+		challenge, err := b.receiveSaslAuthenticateResponse(correlationID)
+		if err != nil {
+			Logger.Printf("Failed to read response while authenticating with SASL to broker %s: %s\n", b.addr, err.Error())
+			return err
+		}
+
+		b.updateIncomingCommunicationMetrics(len(challenge), time.Since(requestTime))
+		msg, err = scramClient.Step(string(challenge))
+		if err != nil {
+			Logger.Println("SASL authentication failed", err)
+			return err
+		}
+	}
+
+	Logger.Println("SASL authentication succeeded")
+	return nil
+}
+
+func (b *Broker) sendSaslAuthenticateRequest(correlationID int32, msg []byte) (int, error) {
+	rb := &SaslAuthenticateRequest{msg}
+	req := &request{correlationID: correlationID, clientID: b.conf.ClientID, body: rb}
+	buf, err := encode(req, b.conf.MetricRegistry)
+	if err != nil {
+		return 0, err
+	}
+
+	if err := b.conn.SetWriteDeadline(time.Now().Add(b.conf.Net.WriteTimeout)); err != nil {
+		return 0, err
+	}
+
+	return b.conn.Write(buf)
+}
+
+func (b *Broker) receiveSaslAuthenticateResponse(correlationID int32) ([]byte, error) {
+	buf := make([]byte, responseLengthSize+correlationIDSize)
+	_, err := io.ReadFull(b.conn, buf)
+	if err != nil {
+		return nil, err
+	}
+
+	header := responseHeader{}
+	err = decode(buf, &header)
+	if err != nil {
+		return nil, err
+	}
+
+	if header.correlationID != correlationID {
+		return nil, fmt.Errorf("correlation ID didn't match, wanted %d, got %d", b.correlationID, header.correlationID)
+	}
+
+	buf = make([]byte, header.length-correlationIDSize)
+	_, err = io.ReadFull(b.conn, buf)
+	if err != nil {
+		return nil, err
+	}
+
+	res := &SaslAuthenticateResponse{}
+	if err := versionedDecode(buf, res, 0); err != nil {
+		return nil, err
+	}
+	if res.Err != ErrNoError {
+		return nil, res.Err
+	}
+	return res.SaslAuthBytes, nil
+}
+
 // Build SASL/OAUTHBEARER initial client response as described by RFC-7628
 // https://tools.ietf.org/html/rfc7628
 func buildClientInitialResponse(token *AccessToken) ([]byte, error) {
-
 	var ext string
 
 	if token.Extensions != nil && len(token.Extensions) > 0 {
 		if _, ok := token.Extensions[SASLExtKeyAuth]; ok {
-			return []byte{}, fmt.Errorf("The extension `%s` is invalid", SASLExtKeyAuth)
+			return []byte{}, fmt.Errorf("the extension `%s` is invalid", SASLExtKeyAuth)
 		}
 		ext = "\x01" + mapToString(token.Extensions, "=", "\x01")
 	}
@@ -970,7 +1172,6 @@
 // mapToString returns a list of key-value pairs ordered by key.
 // keyValSep separates the key from the value. elemSep separates each pair.
 func mapToString(extensions map[string]string, keyValSep string, elemSep string) string {
-
 	buf := make([]string, 0, len(extensions))
 
 	for k, v := range extensions {
@@ -982,10 +1183,25 @@
 	return strings.Join(buf, elemSep)
 }
 
+func (b *Broker) sendSASLPlainAuthClientResponse(correlationID int32) (int, error) {
+	authBytes := []byte("\x00" + b.conf.Net.SASL.User + "\x00" + b.conf.Net.SASL.Password)
+	rb := &SaslAuthenticateRequest{authBytes}
+	req := &request{correlationID: correlationID, clientID: b.conf.ClientID, body: rb}
+	buf, err := encode(req, b.conf.MetricRegistry)
+	if err != nil {
+		return 0, err
+	}
+
+	err = b.conn.SetWriteDeadline(time.Now().Add(b.conf.Net.WriteTimeout))
+	if err != nil {
+		Logger.Printf("Failed to set write deadline when doing SASL auth with broker %s: %s\n", b.addr, err.Error())
+		return 0, err
+	}
+	return b.conn.Write(buf)
+}
+
 func (b *Broker) sendSASLOAuthBearerClientResponse(token *AccessToken, correlationID int32) (int, error) {
-
 	initialResp, err := buildClientInitialResponse(token)
-
 	if err != nil {
 		return 0, err
 	}
@@ -995,7 +1211,6 @@
 	req := &request{correlationID: correlationID, clientID: b.conf.ClientID, body: rb}
 
 	buf, err := encode(req, b.conf.MetricRegistry)
-
 	if err != nil {
 		return 0, err
 	}
@@ -1007,12 +1222,11 @@
 	return b.conn.Write(buf)
 }
 
-func (b *Broker) receiveSASLOAuthBearerServerResponse(correlationID int32) (int, error) {
+func (b *Broker) receiveSASLServerResponse(correlationID int32) (int, error) {
 
-	buf := make([]byte, 8)
+	buf := make([]byte, responseLengthSize+correlationIDSize)
 
 	bytesRead, err := io.ReadFull(b.conn, buf)
-
 	if err != nil {
 		return bytesRead, err
 	}
@@ -1020,7 +1234,6 @@
 	header := responseHeader{}
 
 	err = decode(buf, &header)
-
 	if err != nil {
 		return bytesRead, err
 	}
@@ -1029,12 +1242,10 @@
 		return bytesRead, fmt.Errorf("correlation ID didn't match, wanted %d, got %d", b.correlationID, header.correlationID)
 	}
 
-	buf = make([]byte, header.length-4)
+	buf = make([]byte, header.length-correlationIDSize)
 
 	c, err := io.ReadFull(b.conn, buf)
-
 	bytesRead += c
-
 	if err != nil {
 		return bytesRead, err
 	}
@@ -1045,10 +1256,6 @@
 		return bytesRead, err
 	}
 
-	if err != nil {
-		return bytesRead, err
-	}
-
 	if res.Err != ErrNoError {
 		return bytesRead, res.Err
 	}
@@ -1063,14 +1270,17 @@
 func (b *Broker) updateIncomingCommunicationMetrics(bytes int, requestLatency time.Duration) {
 	b.updateRequestLatencyMetrics(requestLatency)
 	b.responseRate.Mark(1)
+
 	if b.brokerResponseRate != nil {
 		b.brokerResponseRate.Mark(1)
 	}
+
 	responseSize := int64(bytes)
 	b.incomingByteRate.Mark(responseSize)
 	if b.brokerIncomingByteRate != nil {
 		b.brokerIncomingByteRate.Mark(responseSize)
 	}
+
 	b.responseSize.Update(responseSize)
 	if b.brokerResponseSize != nil {
 		b.brokerResponseSize.Update(responseSize)
@@ -1080,9 +1290,11 @@
 func (b *Broker) updateRequestLatencyMetrics(requestLatency time.Duration) {
 	requestLatencyInMs := int64(requestLatency / time.Millisecond)
 	b.requestLatency.Update(requestLatencyInMs)
+
 	if b.brokerRequestLatency != nil {
 		b.brokerRequestLatency.Update(requestLatencyInMs)
 	}
+
 }
 
 func (b *Broker) updateOutgoingCommunicationMetrics(bytes int) {
@@ -1090,13 +1302,44 @@
 	if b.brokerRequestRate != nil {
 		b.brokerRequestRate.Mark(1)
 	}
+
 	requestSize := int64(bytes)
 	b.outgoingByteRate.Mark(requestSize)
 	if b.brokerOutgoingByteRate != nil {
 		b.brokerOutgoingByteRate.Mark(requestSize)
 	}
+
 	b.requestSize.Update(requestSize)
 	if b.brokerRequestSize != nil {
 		b.brokerRequestSize.Update(requestSize)
 	}
+
+}
+
+func (b *Broker) registerMetrics() {
+	b.brokerIncomingByteRate = b.registerMeter("incoming-byte-rate")
+	b.brokerRequestRate = b.registerMeter("request-rate")
+	b.brokerRequestSize = b.registerHistogram("request-size")
+	b.brokerRequestLatency = b.registerHistogram("request-latency-in-ms")
+	b.brokerOutgoingByteRate = b.registerMeter("outgoing-byte-rate")
+	b.brokerResponseRate = b.registerMeter("response-rate")
+	b.brokerResponseSize = b.registerHistogram("response-size")
+}
+
+func (b *Broker) unregisterMetrics() {
+	for _, name := range b.registeredMetrics {
+		b.conf.MetricRegistry.Unregister(name)
+	}
+}
+
+func (b *Broker) registerMeter(name string) metrics.Meter {
+	nameForBroker := getMetricNameForBroker(name, b)
+	b.registeredMetrics = append(b.registeredMetrics, nameForBroker)
+	return metrics.GetOrRegisterMeter(nameForBroker, b.conf.MetricRegistry)
+}
+
+func (b *Broker) registerHistogram(name string) metrics.Histogram {
+	nameForBroker := getMetricNameForBroker(name, b)
+	b.registeredMetrics = append(b.registeredMetrics, nameForBroker)
+	return getOrRegisterHistogram(nameForBroker, b.conf.MetricRegistry)
 }
diff --git a/vendor/gopkg.in/Shopify/sarama.v1/client.go b/vendor/gopkg.in/Shopify/sarama.v1/client.go
index 0016f8f..c4c54b2 100644
--- a/vendor/gopkg.in/Shopify/sarama.v1/client.go
+++ b/vendor/gopkg.in/Shopify/sarama.v1/client.go
@@ -46,6 +46,10 @@
 	// the partition leader.
 	InSyncReplicas(topic string, partitionID int32) ([]int32, error)
 
+	// OfflineReplicas returns the set of all offline replica IDs for the given
+	// partition. Offline replicas are replicas which are offline
+	OfflineReplicas(topic string, partitionID int32) ([]int32, error)
+
 	// RefreshMetadata takes a list of topics and queries the cluster to refresh the
 	// available metadata for those topics. If no topics are provided, it will refresh
 	// metadata for all topics.
@@ -288,7 +292,8 @@
 		partitions = client.cachedPartitions(topic, allPartitions)
 	}
 
-	if partitions == nil {
+	// no partitions found after refresh metadata
+	if len(partitions) == 0 {
 		return nil, ErrUnknownTopicOrPartition
 	}
 
@@ -373,6 +378,31 @@
 	return dupInt32Slice(metadata.Isr), nil
 }
 
+func (client *client) OfflineReplicas(topic string, partitionID int32) ([]int32, error) {
+	if client.Closed() {
+		return nil, ErrClosedClient
+	}
+
+	metadata := client.cachedMetadata(topic, partitionID)
+
+	if metadata == nil {
+		err := client.RefreshMetadata(topic)
+		if err != nil {
+			return nil, err
+		}
+		metadata = client.cachedMetadata(topic, partitionID)
+	}
+
+	if metadata == nil {
+		return nil, ErrUnknownTopicOrPartition
+	}
+
+	if metadata.Err == ErrReplicaNotAvailable {
+		return dupInt32Slice(metadata.OfflineReplicas), metadata.Err
+	}
+	return dupInt32Slice(metadata.OfflineReplicas), nil
+}
+
 func (client *client) Leader(topic string, partitionID int32) (*Broker, error) {
 	if client.Closed() {
 		return nil, ErrClosedClient
@@ -405,7 +435,11 @@
 		}
 	}
 
-	return client.tryRefreshMetadata(topics, client.conf.Metadata.Retry.Max)
+	deadline := time.Time{}
+	if client.conf.Metadata.Timeout > 0 {
+		deadline = time.Now().Add(client.conf.Metadata.Timeout)
+	}
+	return client.tryRefreshMetadata(topics, client.conf.Metadata.Retry.Max, deadline)
 }
 
 func (client *client) GetOffset(topic string, partitionID int32, time int64) (int64, error) {
@@ -707,32 +741,47 @@
 	return nil
 }
 
-func (client *client) tryRefreshMetadata(topics []string, attemptsRemaining int) error {
+func (client *client) tryRefreshMetadata(topics []string, attemptsRemaining int, deadline time.Time) error {
+	pastDeadline := func(backoff time.Duration) bool {
+		if !deadline.IsZero() && time.Now().Add(backoff).After(deadline) {
+			// we are past the deadline
+			return true
+		}
+		return false
+	}
 	retry := func(err error) error {
 		if attemptsRemaining > 0 {
 			backoff := client.computeBackoff(attemptsRemaining)
+			if pastDeadline(backoff) {
+				Logger.Println("client/metadata skipping last retries as we would go past the metadata timeout")
+				return err
+			}
 			Logger.Printf("client/metadata retrying after %dms... (%d attempts remaining)\n", client.conf.Metadata.Retry.Backoff/time.Millisecond, attemptsRemaining)
 			if backoff > 0 {
 				time.Sleep(backoff)
 			}
-			return client.tryRefreshMetadata(topics, attemptsRemaining-1)
+			return client.tryRefreshMetadata(topics, attemptsRemaining-1, deadline)
 		}
 		return err
 	}
 
-	for broker := client.any(); broker != nil; broker = client.any() {
+	broker := client.any()
+	for ; broker != nil && !pastDeadline(0); broker = client.any() {
+		allowAutoTopicCreation := true
 		if len(topics) > 0 {
 			Logger.Printf("client/metadata fetching metadata for %v from broker %s\n", topics, broker.addr)
 		} else {
+			allowAutoTopicCreation = false
 			Logger.Printf("client/metadata fetching metadata for all topics from broker %s\n", broker.addr)
 		}
 
-		req := &MetadataRequest{Topics: topics}
-		if client.conf.Version.IsAtLeast(V0_10_0_0) {
+		req := &MetadataRequest{Topics: topics, AllowAutoTopicCreation: allowAutoTopicCreation}
+		if client.conf.Version.IsAtLeast(V1_0_0_0) {
+			req.Version = 5
+		} else if client.conf.Version.IsAtLeast(V0_10_0_0) {
 			req.Version = 1
 		}
 		response, err := broker.GetMetadata(req)
-
 		switch err.(type) {
 		case nil:
 			allKnownMetaData := len(topics) == 0
@@ -747,6 +796,18 @@
 		case PacketEncodingError:
 			// didn't even send, return the error
 			return err
+
+		case KError:
+			// if SASL auth error return as this _should_ be a non retryable err for all brokers
+			if err.(KError) == ErrSASLAuthenticationFailed {
+				Logger.Println("client/metadata failed SASL authentication")
+				return err
+			}
+			// else remove that broker and try again
+			Logger.Printf("client/metadata got error from broker %d while fetching metadata: %v\n", broker.ID(), err)
+			_ = broker.Close()
+			client.deregisterBroker(broker)
+
 		default:
 			// some other error, remove that broker and try again
 			Logger.Printf("client/metadata got error from broker %d while fetching metadata: %v\n", broker.ID(), err)
@@ -755,6 +816,11 @@
 		}
 	}
 
+	if broker != nil {
+		Logger.Println("client/metadata not fetching metadata from broker %s as we would go past the metadata timeout\n", broker.addr)
+		return retry(ErrOutOfBrokers)
+	}
+
 	Logger.Println("client/metadata no available broker to send metadata request to")
 	client.resurrectDeadBrokers()
 	return retry(ErrOutOfBrokers)
@@ -792,7 +858,7 @@
 
 		switch topic.Err {
 		case ErrNoError:
-			break
+			// no-op
 		case ErrInvalidTopic, ErrTopicAuthorizationFailed: // don't retry, don't store partial results
 			err = topic.Err
 			continue
@@ -802,7 +868,6 @@
 			continue
 		case ErrLeaderNotAvailable: // retry, but store partial partition results
 			retry = true
-			break
 		default: // don't retry, don't store partial results
 			Logger.Printf("Unexpected topic-level metadata error: %s", topic.Err)
 			err = topic.Err
@@ -847,9 +912,8 @@
 		maxRetries := client.conf.Metadata.Retry.Max
 		retries := maxRetries - attemptsRemaining
 		return client.conf.Metadata.Retry.BackoffFunc(retries, maxRetries)
-	} else {
-		return client.conf.Metadata.Retry.Backoff
 	}
+	return client.conf.Metadata.Retry.Backoff
 }
 
 func (client *client) getConsumerMetadata(consumerGroup string, attemptsRemaining int) (*FindCoordinatorResponse, error) {
@@ -911,3 +975,18 @@
 	client.resurrectDeadBrokers()
 	return retry(ErrOutOfBrokers)
 }
+
+// nopCloserClient embeds an existing Client, but disables
+// the Close method (yet all other methods pass
+// through unchanged). This is for use in larger structs
+// where it is undesirable to close the client that was
+// passed in by the caller.
+type nopCloserClient struct {
+	Client
+}
+
+// Close intercepts and purposely does not call the underlying
+// client's Close() method.
+func (ncc *nopCloserClient) Close() error {
+	return nil
+}
diff --git a/vendor/gopkg.in/Shopify/sarama.v1/config.go b/vendor/gopkg.in/Shopify/sarama.v1/config.go
index 9495b7f..e2e6513 100644
--- a/vendor/gopkg.in/Shopify/sarama.v1/config.go
+++ b/vendor/gopkg.in/Shopify/sarama.v1/config.go
@@ -10,6 +10,7 @@
 	"time"
 
 	"github.com/rcrowley/go-metrics"
+	"golang.org/x/net/proxy"
 )
 
 const defaultClientID = "sarama"
@@ -57,18 +58,28 @@
 			// SASLMechanism is the name of the enabled SASL mechanism.
 			// Possible values: OAUTHBEARER, PLAIN (defaults to PLAIN).
 			Mechanism SASLMechanism
+			// Version is the SASL Protocol Version to use
+			// Kafka > 1.x should use V1, except on Azure EventHub which use V0
+			Version int16
 			// Whether or not to send the Kafka SASL handshake first if enabled
 			// (defaults to true). You should only set this to false if you're using
 			// a non-Kafka SASL proxy.
 			Handshake bool
-			//username and password for SASL/PLAIN authentication
+			//username and password for SASL/PLAIN  or SASL/SCRAM authentication
 			User     string
 			Password string
+			// authz id used for SASL/SCRAM authentication
+			SCRAMAuthzID string
+			// SCRAMClientGeneratorFunc is a generator of a user provided implementation of a SCRAM
+			// client used to perform the SCRAM exchange with the server.
+			SCRAMClientGeneratorFunc func() SCRAMClient
 			// TokenProvider is a user-defined callback for generating
 			// access tokens for SASL/OAUTHBEARER auth. See the
 			// AccessTokenProvider interface docs for proper implementation
 			// guidelines.
 			TokenProvider AccessTokenProvider
+
+			GSSAPI GSSAPIConfig
 		}
 
 		// KeepAlive specifies the keep-alive period for an active network connection.
@@ -80,6 +91,14 @@
 		// network being dialed.
 		// If nil, a local address is automatically chosen.
 		LocalAddr net.Addr
+
+		Proxy struct {
+			// Whether or not to use proxy when connecting to the broker
+			// (defaults to false).
+			Enable bool
+			// The proxy dialer to use enabled (defaults to nil).
+			Dialer proxy.Dialer
+		}
 	}
 
 	// Metadata is the namespace for metadata management properties used by the
@@ -107,6 +126,13 @@
 		// and usually more convenient, but can take up a substantial amount of
 		// memory if you have many topics and partitions. Defaults to true.
 		Full bool
+
+		// How long to wait for a successful metadata response.
+		// Disabled by default which means a metadata request against an unreachable
+		// cluster (all brokers are unreachable or unresponsive) can take up to
+		// `Net.[Dial|Read]Timeout * BrokerCount * (Metadata.Retry.Max + 1) + Metadata.Retry.Backoff * Metadata.Retry.Max`
+		// to fail.
+		Timeout time.Duration
 	}
 
 	// Producer is the namespace for configuration related to producing messages,
@@ -333,6 +359,11 @@
 				Max int
 			}
 		}
+
+		// IsolationLevel support 2 mode:
+		// 	- use `ReadUncommitted` (default) to consume and return all messages in message channel
+		//	- use `ReadCommitted` to hide messages that are part of an aborted transaction
+		IsolationLevel IsolationLevel
 	}
 
 	// A user-provided string sent with every request to the brokers for logging,
@@ -370,6 +401,7 @@
 	c.Net.ReadTimeout = 30 * time.Second
 	c.Net.WriteTimeout = 30 * time.Second
 	c.Net.SASL.Handshake = true
+	c.Net.SASL.Version = SASLHandshakeV0
 
 	c.Metadata.Retry.Max = 3
 	c.Metadata.Retry.Backoff = 250 * time.Millisecond
@@ -414,10 +446,10 @@
 // ConfigurationError if the specified values don't make sense.
 func (c *Config) Validate() error {
 	// some configuration values should be warned on but not fail completely, do those first
-	if c.Net.TLS.Enable == false && c.Net.TLS.Config != nil {
+	if !c.Net.TLS.Enable && c.Net.TLS.Config != nil {
 		Logger.Println("Net.TLS is disabled but a non-nil configuration was provided.")
 	}
-	if c.Net.SASL.Enable == false {
+	if !c.Net.SASL.Enable {
 		if c.Net.SASL.User != "" {
 			Logger.Println("Net.SASL is disabled but a non-empty username was provided.")
 		}
@@ -475,22 +507,62 @@
 	case c.Net.KeepAlive < 0:
 		return ConfigurationError("Net.KeepAlive must be >= 0")
 	case c.Net.SASL.Enable:
-		// For backwards compatibility, empty mechanism value defaults to PLAIN
-		isSASLPlain := len(c.Net.SASL.Mechanism) == 0 || c.Net.SASL.Mechanism == SASLTypePlaintext
-		if isSASLPlain {
+		if c.Net.SASL.Mechanism == "" {
+			c.Net.SASL.Mechanism = SASLTypePlaintext
+		}
+
+		switch c.Net.SASL.Mechanism {
+		case SASLTypePlaintext:
 			if c.Net.SASL.User == "" {
 				return ConfigurationError("Net.SASL.User must not be empty when SASL is enabled")
 			}
 			if c.Net.SASL.Password == "" {
 				return ConfigurationError("Net.SASL.Password must not be empty when SASL is enabled")
 			}
-		} else if c.Net.SASL.Mechanism == SASLTypeOAuth {
+		case SASLTypeOAuth:
 			if c.Net.SASL.TokenProvider == nil {
-				return ConfigurationError("An AccessTokenProvider instance must be provided to Net.SASL.User.TokenProvider")
+				return ConfigurationError("An AccessTokenProvider instance must be provided to Net.SASL.TokenProvider")
 			}
-		} else {
-			msg := fmt.Sprintf("The SASL mechanism configuration is invalid. Possible values are `%s` and `%s`",
-				SASLTypeOAuth, SASLTypePlaintext)
+		case SASLTypeSCRAMSHA256, SASLTypeSCRAMSHA512:
+			if c.Net.SASL.User == "" {
+				return ConfigurationError("Net.SASL.User must not be empty when SASL is enabled")
+			}
+			if c.Net.SASL.Password == "" {
+				return ConfigurationError("Net.SASL.Password must not be empty when SASL is enabled")
+			}
+			if c.Net.SASL.SCRAMClientGeneratorFunc == nil {
+				return ConfigurationError("A SCRAMClientGeneratorFunc function must be provided to Net.SASL.SCRAMClientGeneratorFunc")
+			}
+		case SASLTypeGSSAPI:
+			if c.Net.SASL.GSSAPI.ServiceName == "" {
+				return ConfigurationError("Net.SASL.GSSAPI.ServiceName must not be empty when GSS-API mechanism is used")
+			}
+
+			if c.Net.SASL.GSSAPI.AuthType == KRB5_USER_AUTH {
+				if c.Net.SASL.GSSAPI.Password == "" {
+					return ConfigurationError("Net.SASL.GSSAPI.Password must not be empty when GSS-API " +
+						"mechanism is used and Net.SASL.GSSAPI.AuthType = KRB5_USER_AUTH")
+				}
+			} else if c.Net.SASL.GSSAPI.AuthType == KRB5_KEYTAB_AUTH {
+				if c.Net.SASL.GSSAPI.KeyTabPath == "" {
+					return ConfigurationError("Net.SASL.GSSAPI.KeyTabPath must not be empty when GSS-API mechanism is used" +
+						" and  Net.SASL.GSSAPI.AuthType = KRB5_KEYTAB_AUTH")
+				}
+			} else {
+				return ConfigurationError("Net.SASL.GSSAPI.AuthType is invalid. Possible values are KRB5_USER_AUTH and KRB5_KEYTAB_AUTH")
+			}
+			if c.Net.SASL.GSSAPI.KerberosConfigPath == "" {
+				return ConfigurationError("Net.SASL.GSSAPI.KerberosConfigPath must not be empty when GSS-API mechanism is used")
+			}
+			if c.Net.SASL.GSSAPI.Username == "" {
+				return ConfigurationError("Net.SASL.GSSAPI.Username must not be empty when GSS-API mechanism is used")
+			}
+			if c.Net.SASL.GSSAPI.Realm == "" {
+				return ConfigurationError("Net.SASL.GSSAPI.Realm must not be empty when GSS-API mechanism is used")
+			}
+		default:
+			msg := fmt.Sprintf("The SASL mechanism configuration is invalid. Possible values are `%s`, `%s`, `%s`, `%s` and `%s`",
+				SASLTypeOAuth, SASLTypePlaintext, SASLTypeSCRAMSHA256, SASLTypeSCRAMSHA512, SASLTypeGSSAPI)
 			return ConfigurationError(msg)
 		}
 	}
@@ -584,6 +656,13 @@
 		return ConfigurationError("Consumer.Offsets.Initial must be OffsetOldest or OffsetNewest")
 	case c.Consumer.Offsets.Retry.Max < 0:
 		return ConfigurationError("Consumer.Offsets.Retry.Max must be >= 0")
+	case c.Consumer.IsolationLevel != ReadUncommitted && c.Consumer.IsolationLevel != ReadCommitted:
+		return ConfigurationError("Consumer.IsolationLevel must be ReadUncommitted or ReadCommitted")
+	}
+
+	// validate IsolationLevel
+	if c.Consumer.IsolationLevel == ReadCommitted && !c.Version.IsAtLeast(V0_11_0_0) {
+		return ConfigurationError("ReadCommitted requires Version >= V0_11_0_0")
 	}
 
 	// validate the Consumer Group values
diff --git a/vendor/gopkg.in/Shopify/sarama.v1/config_resource_type.go b/vendor/gopkg.in/Shopify/sarama.v1/config_resource_type.go
index 848cc9c..5399d75 100644
--- a/vendor/gopkg.in/Shopify/sarama.v1/config_resource_type.go
+++ b/vendor/gopkg.in/Shopify/sarama.v1/config_resource_type.go
@@ -1,15 +1,22 @@
 package sarama
 
+//ConfigResourceType is a type for config resource
 type ConfigResourceType int8
 
 // Taken from :
 // https://cwiki.apache.org/confluence/display/KAFKA/KIP-133%3A+Describe+and+Alter+Configs+Admin+APIs#KIP-133:DescribeandAlterConfigsAdminAPIs-WireFormattypes
 
 const (
-	UnknownResource ConfigResourceType = 0
-	AnyResource     ConfigResourceType = 1
-	TopicResource   ConfigResourceType = 2
-	GroupResource   ConfigResourceType = 3
-	ClusterResource ConfigResourceType = 4
-	BrokerResource  ConfigResourceType = 5
+	//UnknownResource constant type
+	UnknownResource ConfigResourceType = iota
+	//AnyResource constant type
+	AnyResource
+	//TopicResource constant type
+	TopicResource
+	//GroupResource constant type
+	GroupResource
+	//ClusterResource constant type
+	ClusterResource
+	//BrokerResource constant type
+	BrokerResource
 )
diff --git a/vendor/gopkg.in/Shopify/sarama.v1/consumer.go b/vendor/gopkg.in/Shopify/sarama.v1/consumer.go
index ce72ff1..72c4d7c 100644
--- a/vendor/gopkg.in/Shopify/sarama.v1/consumer.go
+++ b/vendor/gopkg.in/Shopify/sarama.v1/consumer.go
@@ -3,20 +3,24 @@
 import (
 	"errors"
 	"fmt"
+	"math"
 	"sync"
 	"sync/atomic"
 	"time"
+
+	"github.com/rcrowley/go-metrics"
 )
 
 // ConsumerMessage encapsulates a Kafka message returned by the consumer.
 type ConsumerMessage struct {
-	Key, Value     []byte
-	Topic          string
-	Partition      int32
-	Offset         int64
+	Headers        []*RecordHeader // only set if kafka is version 0.11+
 	Timestamp      time.Time       // only set if kafka is version 0.10+, inner message timestamp
 	BlockTimestamp time.Time       // only set if kafka is version 0.10+, outer (compressed) block timestamp
-	Headers        []*RecordHeader // only set if kafka is version 0.11+
+
+	Key, Value []byte
+	Topic      string
+	Partition  int32
+	Offset     int64
 }
 
 // ConsumerError is what is provided to the user when an error occurs.
@@ -43,13 +47,7 @@
 // Consumer manages PartitionConsumers which process Kafka messages from brokers. You MUST call Close()
 // on a consumer to avoid leaks, it will not be garbage-collected automatically when it passes out of
 // scope.
-//
-// Sarama's Consumer type does not currently support automatic consumer-group rebalancing and offset tracking.
-// For Zookeeper-based tracking (Kafka 0.8.2 and earlier), the https://github.com/wvanbergen/kafka library
-// builds on Sarama to add this support. For Kafka-based tracking (Kafka 0.9 and later), the
-// https://github.com/bsm/sarama-cluster library builds on Sarama to add this support.
 type Consumer interface {
-
 	// Topics returns the set of available topics as retrieved from the cluster
 	// metadata. This method is the same as Client.Topics(), and is provided for
 	// convenience.
@@ -75,13 +73,11 @@
 }
 
 type consumer struct {
-	client    Client
-	conf      *Config
-	ownClient bool
-
-	lock            sync.Mutex
+	conf            *Config
 	children        map[string]map[int32]*partitionConsumer
 	brokerConsumers map[*Broker]*brokerConsumer
+	client          Client
+	lock            sync.Mutex
 }
 
 // NewConsumer creates a new consumer using the given broker addresses and configuration.
@@ -90,18 +86,19 @@
 	if err != nil {
 		return nil, err
 	}
-
-	c, err := NewConsumerFromClient(client)
-	if err != nil {
-		return nil, err
-	}
-	c.(*consumer).ownClient = true
-	return c, nil
+	return newConsumer(client)
 }
 
 // NewConsumerFromClient creates a new consumer using the given client. It is still
 // necessary to call Close() on the underlying client when shutting down this consumer.
 func NewConsumerFromClient(client Client) (Consumer, error) {
+	// For clients passed in by the client, ensure we don't
+	// call Close() on it.
+	cli := &nopCloserClient{client}
+	return newConsumer(cli)
+}
+
+func newConsumer(client Client) (Consumer, error) {
 	// Check that we are not dealing with a closed Client before processing any other arguments
 	if client.Closed() {
 		return nil, ErrClosedClient
@@ -118,10 +115,7 @@
 }
 
 func (c *consumer) Close() error {
-	if c.ownClient {
-		return c.client.Close()
-	}
-	return nil
+	return c.client.Close()
 }
 
 func (c *consumer) Topics() ([]string, error) {
@@ -261,12 +255,11 @@
 // or a separate goroutine. Check out the Consumer examples to see implementations of these different approaches.
 //
 // To terminate such a for/range loop while the loop is executing, call AsyncClose. This will kick off the process of
-// consumer tear-down & return imediately. Continue to loop, servicing the Messages channel until the teardown process
+// consumer tear-down & return immediately. Continue to loop, servicing the Messages channel until the teardown process
 // AsyncClose initiated closes it (thus terminating the for/range loop). If you've already ceased reading Messages, call
 // Close; this will signal the PartitionConsumer's goroutines to begin shutting down (just like AsyncClose), but will
 // also drain the Messages channel, harvest all errors & return them once cleanup has completed.
 type PartitionConsumer interface {
-
 	// AsyncClose initiates a shutdown of the PartitionConsumer. This method will return immediately, after which you
 	// should continue to service the 'Messages' and 'Errors' channels until they are empty. It is required to call this
 	// function, or Close before a consumer object passes out of scope, as it will otherwise leak memory. You must call
@@ -298,24 +291,22 @@
 
 type partitionConsumer struct {
 	highWaterMarkOffset int64 // must be at the top of the struct because https://golang.org/pkg/sync/atomic/#pkg-note-BUG
-	consumer            *consumer
-	conf                *Config
-	topic               string
-	partition           int32
 
+	consumer *consumer
+	conf     *Config
 	broker   *brokerConsumer
 	messages chan *ConsumerMessage
 	errors   chan *ConsumerError
 	feeder   chan *FetchResponse
 
 	trigger, dying chan none
-	responseResult error
 	closeOnce      sync.Once
-
-	fetchSize int32
-	offset    int64
-
-	retries int32
+	topic          string
+	partition      int32
+	responseResult error
+	fetchSize      int32
+	offset         int64
+	retries        int32
 }
 
 var errTimedOut = errors.New("timed out feeding messages to the user") // not user-facing
@@ -338,9 +329,8 @@
 	if child.conf.Consumer.Retry.BackoffFunc != nil {
 		retries := atomic.AddInt32(&child.retries, 1)
 		return child.conf.Consumer.Retry.BackoffFunc(int(retries))
-	} else {
-		return child.conf.Consumer.Retry.Backoff
 	}
+	return child.conf.Consumer.Retry.Backoff
 }
 
 func (child *partitionConsumer) dispatcher() {
@@ -432,12 +422,6 @@
 func (child *partitionConsumer) Close() error {
 	child.AsyncClose()
 
-	go withRecover(func() {
-		for range child.messages {
-			// drain
-		}
-	})
-
 	var errors ConsumerErrors
 	for err := range child.errors {
 		errors = append(errors, err)
@@ -469,14 +453,22 @@
 		for i, msg := range msgs {
 		messageSelect:
 			select {
+			case <-child.dying:
+				child.broker.acks.Done()
+				continue feederLoop
 			case child.messages <- msg:
 				firstAttempt = true
 			case <-expiryTicker.C:
 				if !firstAttempt {
 					child.responseResult = errTimedOut
 					child.broker.acks.Done()
+				remainingLoop:
 					for _, msg = range msgs[i:] {
-						child.messages <- msg
+						select {
+						case child.messages <- msg:
+						case <-child.dying:
+							break remainingLoop
+						}
 					}
 					child.broker.input <- child
 					continue feederLoop
@@ -532,7 +524,8 @@
 }
 
 func (child *partitionConsumer) parseRecords(batch *RecordBatch) ([]*ConsumerMessage, error) {
-	var messages []*ConsumerMessage
+	messages := make([]*ConsumerMessage, 0, len(batch.Records))
+
 	for _, rec := range batch.Records {
 		offset := batch.FirstOffset + rec.OffsetDelta
 		if offset < child.offset {
@@ -560,6 +553,23 @@
 }
 
 func (child *partitionConsumer) parseResponse(response *FetchResponse) ([]*ConsumerMessage, error) {
+	var (
+		metricRegistry          = child.conf.MetricRegistry
+		consumerBatchSizeMetric metrics.Histogram
+	)
+
+	if metricRegistry != nil {
+		consumerBatchSizeMetric = getOrRegisterHistogram("consumer-batch-size", metricRegistry)
+	}
+
+	// If request was throttled and empty we log and return without error
+	if response.ThrottleTime != time.Duration(0) && len(response.Blocks) == 0 {
+		Logger.Printf(
+			"consumer/broker/%d FetchResponse throttled %v\n",
+			child.broker.broker.ID(), response.ThrottleTime)
+		return nil, nil
+	}
+
 	block := response.GetBlock(child.topic, child.partition)
 	if block == nil {
 		return nil, ErrIncompleteResponse
@@ -573,6 +583,9 @@
 	if err != nil {
 		return nil, err
 	}
+
+	consumerBatchSizeMetric.Update(int64(nRecs))
+
 	if nRecs == 0 {
 		partialTrailingMessage, err := block.isPartial()
 		if err != nil {
@@ -587,6 +600,10 @@
 				child.offset++ // skip this one so we can keep processing future messages
 			} else {
 				child.fetchSize *= 2
+				// check int32 overflow
+				if child.fetchSize < 0 {
+					child.fetchSize = math.MaxInt32
+				}
 				if child.conf.Consumer.Fetch.Max > 0 && child.fetchSize > child.conf.Consumer.Fetch.Max {
 					child.fetchSize = child.conf.Consumer.Fetch.Max
 				}
@@ -600,6 +617,12 @@
 	child.fetchSize = child.conf.Consumer.Fetch.Default
 	atomic.StoreInt64(&child.highWaterMarkOffset, block.HighWaterMarkOffset)
 
+	// abortedProducerIDs contains producerID which message should be ignored as uncommitted
+	// - producerID are added when the partitionConsumer iterate over the offset at which an aborted transaction begins (abortedTransaction.FirstOffset)
+	// - producerID are removed when partitionConsumer iterate over an aborted controlRecord, meaning the aborted transaction for this producer is over
+	abortedProducerIDs := make(map[int64]struct{}, len(block.AbortedTransactions))
+	abortedTransactions := block.getAbortedTransactions()
+
 	messages := []*ConsumerMessage{}
 	for _, records := range block.RecordsSet {
 		switch records.recordsType {
@@ -611,13 +634,55 @@
 
 			messages = append(messages, messageSetMessages...)
 		case defaultRecords:
+			// Consume remaining abortedTransaction up to last offset of current batch
+			for _, txn := range abortedTransactions {
+				if txn.FirstOffset > records.RecordBatch.LastOffset() {
+					break
+				}
+				abortedProducerIDs[txn.ProducerID] = struct{}{}
+				// Pop abortedTransactions so that we never add it again
+				abortedTransactions = abortedTransactions[1:]
+			}
+
 			recordBatchMessages, err := child.parseRecords(records.RecordBatch)
 			if err != nil {
 				return nil, err
 			}
-			if control, err := records.isControl(); err != nil || control {
+
+			// Parse and commit offset but do not expose messages that are:
+			// - control records
+			// - part of an aborted transaction when set to `ReadCommitted`
+
+			// control record
+			isControl, err := records.isControl()
+			if err != nil {
+				// I don't know why there is this continue in case of error to begin with
+				// Safe bet is to ignore control messages if ReadUncommitted
+				// and block on them in case of error and ReadCommitted
+				if child.conf.Consumer.IsolationLevel == ReadCommitted {
+					return nil, err
+				}
 				continue
 			}
+			if isControl {
+				controlRecord, err := records.getControlRecord()
+				if err != nil {
+					return nil, err
+				}
+
+				if controlRecord.Type == ControlRecordAbort {
+					delete(abortedProducerIDs, records.RecordBatch.ProducerID)
+				}
+				continue
+			}
+
+			// filter aborted transactions
+			if child.conf.Consumer.IsolationLevel == ReadCommitted {
+				_, isAborted := abortedProducerIDs[records.RecordBatch.ProducerID]
+				if records.RecordBatch.IsTransactional && isAborted {
+					continue
+				}
+			}
 
 			messages = append(messages, recordBatchMessages...)
 		default:
@@ -628,15 +693,13 @@
 	return messages, nil
 }
 
-// brokerConsumer
-
 type brokerConsumer struct {
 	consumer         *consumer
 	broker           *Broker
 	input            chan *partitionConsumer
 	newSubscriptions chan []*partitionConsumer
-	wait             chan none
 	subscriptions    map[*partitionConsumer]none
+	wait             chan none
 	acks             sync.WaitGroup
 	refs             int
 }
@@ -658,14 +721,14 @@
 	return bc
 }
 
+// The subscriptionManager constantly accepts new subscriptions on `input` (even when the main subscriptionConsumer
+// goroutine is in the middle of a network request) and batches it up. The main worker goroutine picks
+// up a batch of new subscriptions between every network request by reading from `newSubscriptions`, so we give
+// it nil if no new subscriptions are available. We also write to `wait` only when new subscriptions is available,
+// so the main goroutine can block waiting for work if it has none.
 func (bc *brokerConsumer) subscriptionManager() {
 	var buffer []*partitionConsumer
 
-	// The subscriptionManager constantly accepts new subscriptions on `input` (even when the main subscriptionConsumer
-	// goroutine is in the middle of a network request) and batches it up. The main worker goroutine picks
-	// up a batch of new subscriptions between every network request by reading from `newSubscriptions`, so we give
-	// it nil if no new subscriptions are available. We also write to `wait` only when new subscriptions is available,
-	// so the main goroutine can block waiting for work if it has none.
 	for {
 		if len(buffer) > 0 {
 			select {
@@ -698,10 +761,10 @@
 	close(bc.newSubscriptions)
 }
 
+//subscriptionConsumer ensures we will get nil right away if no new subscriptions is available
 func (bc *brokerConsumer) subscriptionConsumer() {
 	<-bc.wait // wait for our first piece of work
 
-	// the subscriptionConsumer ensures we will get nil right away if no new subscriptions is available
 	for newSubscriptions := range bc.newSubscriptions {
 		bc.updateSubscriptions(newSubscriptions)
 
@@ -742,20 +805,20 @@
 			close(child.trigger)
 			delete(bc.subscriptions, child)
 		default:
-			break
+			// no-op
 		}
 	}
 }
 
+//handleResponses handles the response codes left for us by our subscriptions, and abandons ones that have been closed
 func (bc *brokerConsumer) handleResponses() {
-	// handles the response codes left for us by our subscriptions, and abandons ones that have been closed
 	for child := range bc.subscriptions {
 		result := child.responseResult
 		child.responseResult = nil
 
 		switch result {
 		case nil:
-			break
+			// no-op
 		case errTimedOut:
 			Logger.Printf("consumer/broker/%d abandoned subscription to %s/%d because consuming was taking too long\n",
 				bc.broker.ID(), child.topic, child.partition)
@@ -822,7 +885,7 @@
 	}
 	if bc.consumer.conf.Version.IsAtLeast(V0_11_0_0) {
 		request.Version = 4
-		request.Isolation = ReadUncommitted // We don't support yet transactions.
+		request.Isolation = bc.consumer.conf.Consumer.IsolationLevel
 	}
 
 	for child := range bc.subscriptions {
diff --git a/vendor/gopkg.in/Shopify/sarama.v1/consumer_group.go b/vendor/gopkg.in/Shopify/sarama.v1/consumer_group.go
index 8c8babc..8de9513 100644
--- a/vendor/gopkg.in/Shopify/sarama.v1/consumer_group.go
+++ b/vendor/gopkg.in/Shopify/sarama.v1/consumer_group.go
@@ -52,8 +52,7 @@
 }
 
 type consumerGroup struct {
-	client    Client
-	ownClient bool
+	client Client
 
 	config   *Config
 	consumer Consumer
@@ -73,20 +72,24 @@
 		return nil, err
 	}
 
-	c, err := NewConsumerGroupFromClient(groupID, client)
+	c, err := newConsumerGroup(groupID, client)
 	if err != nil {
 		_ = client.Close()
-		return nil, err
 	}
-
-	c.(*consumerGroup).ownClient = true
-	return c, nil
+	return c, err
 }
 
 // NewConsumerGroupFromClient creates a new consumer group using the given client. It is still
 // necessary to call Close() on the underlying client when shutting down this consumer.
 // PLEASE NOTE: consumer groups can only re-use but not share clients.
 func NewConsumerGroupFromClient(groupID string, client Client) (ConsumerGroup, error) {
+	// For clients passed in by the client, ensure we don't
+	// call Close() on it.
+	cli := &nopCloserClient{client}
+	return newConsumerGroup(groupID, cli)
+}
+
+func newConsumerGroup(groupID string, client Client) (ConsumerGroup, error) {
 	config := client.Config()
 	if !config.Version.IsAtLeast(V0_10_2_0) {
 		return nil, ConfigurationError("consumer groups require Version to be >= V0_10_2_0")
@@ -131,10 +134,8 @@
 			err = e
 		}
 
-		if c.ownClient {
-			if e := c.client.Close(); e != nil {
-				err = e
-			}
+		if e := c.client.Close(); e != nil {
+			err = e
 		}
 	})
 	return
@@ -162,14 +163,8 @@
 		return err
 	}
 
-	// Get coordinator
-	coordinator, err := c.client.Coordinator(c.groupID)
-	if err != nil {
-		return err
-	}
-
 	// Init session
-	sess, err := c.newSession(ctx, coordinator, topics, handler, c.config.Consumer.Group.Rebalance.Retry.Max)
+	sess, err := c.newSession(ctx, topics, handler, c.config.Consumer.Group.Rebalance.Retry.Max)
 	if err == ErrClosedClient {
 		return ErrClosedConsumerGroup
 	} else if err != nil {
@@ -183,7 +178,33 @@
 	return sess.release(true)
 }
 
-func (c *consumerGroup) newSession(ctx context.Context, coordinator *Broker, topics []string, handler ConsumerGroupHandler, retries int) (*consumerGroupSession, error) {
+func (c *consumerGroup) retryNewSession(ctx context.Context, topics []string, handler ConsumerGroupHandler, retries int, refreshCoordinator bool) (*consumerGroupSession, error) {
+	select {
+	case <-c.closed:
+		return nil, ErrClosedConsumerGroup
+	case <-time.After(c.config.Consumer.Group.Rebalance.Retry.Backoff):
+	}
+
+	if refreshCoordinator {
+		err := c.client.RefreshCoordinator(c.groupID)
+		if err != nil {
+			return c.retryNewSession(ctx, topics, handler, retries, true)
+		}
+	}
+
+	return c.newSession(ctx, topics, handler, retries-1)
+}
+
+func (c *consumerGroup) newSession(ctx context.Context, topics []string, handler ConsumerGroupHandler, retries int) (*consumerGroupSession, error) {
+	coordinator, err := c.client.Coordinator(c.groupID)
+	if err != nil {
+		if retries <= 0 {
+			return nil, err
+		}
+
+		return c.retryNewSession(ctx, topics, handler, retries, true)
+	}
+
 	// Join consumer group
 	join, err := c.joinGroupRequest(coordinator, topics)
 	if err != nil {
@@ -195,19 +216,19 @@
 		c.memberID = join.MemberId
 	case ErrUnknownMemberId, ErrIllegalGeneration: // reset member ID and retry immediately
 		c.memberID = ""
-		return c.newSession(ctx, coordinator, topics, handler, retries)
+		return c.newSession(ctx, topics, handler, retries)
+	case ErrNotCoordinatorForConsumer: // retry after backoff with coordinator refresh
+		if retries <= 0 {
+			return nil, join.Err
+		}
+
+		return c.retryNewSession(ctx, topics, handler, retries, true)
 	case ErrRebalanceInProgress: // retry after backoff
 		if retries <= 0 {
 			return nil, join.Err
 		}
 
-		select {
-		case <-c.closed:
-			return nil, ErrClosedConsumerGroup
-		case <-time.After(c.config.Consumer.Group.Rebalance.Retry.Backoff):
-		}
-
-		return c.newSession(ctx, coordinator, topics, handler, retries-1)
+		return c.retryNewSession(ctx, topics, handler, retries, false)
 	default:
 		return nil, join.Err
 	}
@@ -236,19 +257,19 @@
 	case ErrNoError:
 	case ErrUnknownMemberId, ErrIllegalGeneration: // reset member ID and retry immediately
 		c.memberID = ""
-		return c.newSession(ctx, coordinator, topics, handler, retries)
+		return c.newSession(ctx, topics, handler, retries)
+	case ErrNotCoordinatorForConsumer: // retry after backoff with coordinator refresh
+		if retries <= 0 {
+			return nil, sync.Err
+		}
+
+		return c.retryNewSession(ctx, topics, handler, retries, true)
 	case ErrRebalanceInProgress: // retry after backoff
 		if retries <= 0 {
 			return nil, sync.Err
 		}
 
-		select {
-		case <-c.closed:
-			return nil, ErrClosedConsumerGroup
-		case <-time.After(c.config.Consumer.Group.Rebalance.Retry.Backoff):
-		}
-
-		return c.newSession(ctx, coordinator, topics, handler, retries-1)
+		return c.retryNewSession(ctx, topics, handler, retries, false)
 	default:
 		return nil, sync.Err
 	}
@@ -613,7 +634,7 @@
 	s.releaseOnce.Do(func() {
 		if withCleanup {
 			if e := s.handler.Cleanup(s); e != nil {
-				s.parent.handleError(err, "", -1)
+				s.parent.handleError(e, "", -1)
 				err = e
 			}
 		}
diff --git a/vendor/gopkg.in/Shopify/sarama.v1/control_record.go b/vendor/gopkg.in/Shopify/sarama.v1/control_record.go
new file mode 100644
index 0000000..9b75ab5
--- /dev/null
+++ b/vendor/gopkg.in/Shopify/sarama.v1/control_record.go
@@ -0,0 +1,72 @@
+package sarama
+
+//ControlRecordType ...
+type ControlRecordType int
+
+const (
+	//ControlRecordAbort is a control record for abort
+	ControlRecordAbort ControlRecordType = iota
+	//ControlRecordCommit is a control record for commit
+	ControlRecordCommit
+	//ControlRecordUnknown is a control record of unknown type
+	ControlRecordUnknown
+)
+
+// Control records are returned as a record by fetchRequest
+// However unlike "normal" records, they mean nothing application wise.
+// They only serve internal logic for supporting transactions.
+type ControlRecord struct {
+	Version          int16
+	CoordinatorEpoch int32
+	Type             ControlRecordType
+}
+
+func (cr *ControlRecord) decode(key, value packetDecoder) error {
+	var err error
+	cr.Version, err = value.getInt16()
+	if err != nil {
+		return err
+	}
+
+	cr.CoordinatorEpoch, err = value.getInt32()
+	if err != nil {
+		return err
+	}
+
+	// There a version for the value part AND the key part. And I have no idea if they are supposed to match or not
+	// Either way, all these version can only be 0 for now
+	cr.Version, err = key.getInt16()
+	if err != nil {
+		return err
+	}
+
+	recordType, err := key.getInt16()
+	if err != nil {
+		return err
+	}
+
+	switch recordType {
+	case 0:
+		cr.Type = ControlRecordAbort
+	case 1:
+		cr.Type = ControlRecordCommit
+	default:
+		// from JAVA implementation:
+		// UNKNOWN is used to indicate a control type which the client is not aware of and should be ignored
+		cr.Type = ControlRecordUnknown
+	}
+	return nil
+}
+
+func (cr *ControlRecord) encode(key, value packetEncoder) {
+	value.putInt16(cr.Version)
+	value.putInt32(cr.CoordinatorEpoch)
+	key.putInt16(cr.Version)
+
+	switch cr.Type {
+	case ControlRecordAbort:
+		key.putInt16(0)
+	case ControlRecordCommit:
+		key.putInt16(1)
+	}
+}
diff --git a/vendor/gopkg.in/Shopify/sarama.v1/crc32_field.go b/vendor/gopkg.in/Shopify/sarama.v1/crc32_field.go
index 1f14443..38189a3 100644
--- a/vendor/gopkg.in/Shopify/sarama.v1/crc32_field.go
+++ b/vendor/gopkg.in/Shopify/sarama.v1/crc32_field.go
@@ -4,6 +4,7 @@
 	"encoding/binary"
 	"fmt"
 	"hash/crc32"
+	"sync"
 )
 
 type crcPolynomial int8
@@ -13,6 +14,22 @@
 	crcCastagnoli
 )
 
+var crc32FieldPool = sync.Pool{}
+
+func acquireCrc32Field(polynomial crcPolynomial) *crc32Field {
+	val := crc32FieldPool.Get()
+	if val != nil {
+		c := val.(*crc32Field)
+		c.polynomial = polynomial
+		return c
+	}
+	return newCRC32Field(polynomial)
+}
+
+func releaseCrc32Field(c *crc32Field) {
+	crc32FieldPool.Put(c)
+}
+
 var castagnoliTable = crc32.MakeTable(crc32.Castagnoli)
 
 // crc32Field implements the pushEncoder and pushDecoder interfaces for calculating CRC32s.
diff --git a/vendor/gopkg.in/Shopify/sarama.v1/create_partitions_response.go b/vendor/gopkg.in/Shopify/sarama.v1/create_partitions_response.go
index abd621c..bb18204 100644
--- a/vendor/gopkg.in/Shopify/sarama.v1/create_partitions_response.go
+++ b/vendor/gopkg.in/Shopify/sarama.v1/create_partitions_response.go
@@ -1,6 +1,9 @@
 package sarama
 
-import "time"
+import (
+	"fmt"
+	"time"
+)
 
 type CreatePartitionsResponse struct {
 	ThrottleTime         time.Duration
@@ -69,6 +72,14 @@
 	ErrMsg *string
 }
 
+func (t *TopicPartitionError) Error() string {
+	text := t.Err.Error()
+	if t.ErrMsg != nil {
+		text = fmt.Sprintf("%s - %s", text, *t.ErrMsg)
+	}
+	return text
+}
+
 func (t *TopicPartitionError) encode(pe packetEncoder) error {
 	pe.putInt16(int16(t.Err))
 
diff --git a/vendor/gopkg.in/Shopify/sarama.v1/create_topics_response.go b/vendor/gopkg.in/Shopify/sarama.v1/create_topics_response.go
index 66207e0..a493e02 100644
--- a/vendor/gopkg.in/Shopify/sarama.v1/create_topics_response.go
+++ b/vendor/gopkg.in/Shopify/sarama.v1/create_topics_response.go
@@ -1,6 +1,9 @@
 package sarama
 
-import "time"
+import (
+	"fmt"
+	"time"
+)
 
 type CreateTopicsResponse struct {
 	Version      int16
@@ -83,6 +86,14 @@
 	ErrMsg *string
 }
 
+func (t *TopicError) Error() string {
+	text := t.Err.Error()
+	if t.ErrMsg != nil {
+		text = fmt.Sprintf("%s - %s", text, *t.ErrMsg)
+	}
+	return text
+}
+
 func (t *TopicError) encode(pe packetEncoder, version int16) error {
 	pe.putInt16(int16(t.Err))
 
diff --git a/vendor/gopkg.in/Shopify/sarama.v1/describe_configs_response.go b/vendor/gopkg.in/Shopify/sarama.v1/describe_configs_response.go
index 63fb6ea..5737232 100644
--- a/vendor/gopkg.in/Shopify/sarama.v1/describe_configs_response.go
+++ b/vendor/gopkg.in/Shopify/sarama.v1/describe_configs_response.go
@@ -26,12 +26,12 @@
 }
 
 const (
-	SourceUnknown              ConfigSource = 0
-	SourceTopic                ConfigSource = 1
-	SourceDynamicBroker        ConfigSource = 2
-	SourceDynamicDefaultBroker ConfigSource = 3
-	SourceStaticBroker         ConfigSource = 4
-	SourceDefault              ConfigSource = 5
+	SourceUnknown ConfigSource = iota
+	SourceTopic
+	SourceDynamicBroker
+	SourceDynamicDefaultBroker
+	SourceStaticBroker
+	SourceDefault
 )
 
 type DescribeConfigsResponse struct {
diff --git a/vendor/gopkg.in/Shopify/sarama.v1/dev.yml b/vendor/gopkg.in/Shopify/sarama.v1/dev.yml
index 97eed3a..3f4d569 100644
--- a/vendor/gopkg.in/Shopify/sarama.v1/dev.yml
+++ b/vendor/gopkg.in/Shopify/sarama.v1/dev.yml
@@ -2,7 +2,7 @@
 
 up:
   - go:
-      version: '1.11'
+      version: '1.12'
 
 commands:
   test:
diff --git a/vendor/gopkg.in/Shopify/sarama.v1/errors.go b/vendor/gopkg.in/Shopify/sarama.v1/errors.go
index 87a4c61..8ecb652 100644
--- a/vendor/gopkg.in/Shopify/sarama.v1/errors.go
+++ b/vendor/gopkg.in/Shopify/sarama.v1/errors.go
@@ -161,6 +161,11 @@
 	ErrFencedLeaderEpoch                  KError = 74
 	ErrUnknownLeaderEpoch                 KError = 75
 	ErrUnsupportedCompressionType         KError = 76
+	ErrStaleBrokerEpoch                   KError = 77
+	ErrOffsetNotAvailable                 KError = 78
+	ErrMemberIdRequired                   KError = 79
+	ErrPreferredLeaderNotAvailable        KError = 80
+	ErrGroupMaxSizeReached                KError = 81
 )
 
 func (err KError) Error() string {
@@ -323,6 +328,16 @@
 		return "kafka server: The leader epoch in the request is newer than the epoch on the broker."
 	case ErrUnsupportedCompressionType:
 		return "kafka server: The requesting client does not support the compression type of given partition."
+	case ErrStaleBrokerEpoch:
+		return "kafka server: Broker epoch has changed"
+	case ErrOffsetNotAvailable:
+		return "kafka server: The leader high watermark has not caught up from a recent leader election so the offsets cannot be guaranteed to be monotonically increasing"
+	case ErrMemberIdRequired:
+		return "kafka server: The group member needs to have a valid member id before actually entering a consumer group"
+	case ErrPreferredLeaderNotAvailable:
+		return "kafka server: The preferred leader was not available"
+	case ErrGroupMaxSizeReached:
+		return "kafka server: Consumer group The consumer group has reached its max size. already has the configured maximum number of members."
 	}
 
 	return fmt.Sprintf("Unknown error, how did this happen? Error code = %d", err)
diff --git a/vendor/gopkg.in/Shopify/sarama.v1/fetch_request.go b/vendor/gopkg.in/Shopify/sarama.v1/fetch_request.go
index 462ab8a..4db9ddd 100644
--- a/vendor/gopkg.in/Shopify/sarama.v1/fetch_request.go
+++ b/vendor/gopkg.in/Shopify/sarama.v1/fetch_request.go
@@ -36,8 +36,8 @@
 type IsolationLevel int8
 
 const (
-	ReadUncommitted IsolationLevel = 0
-	ReadCommitted   IsolationLevel = 1
+	ReadUncommitted IsolationLevel = iota
+	ReadCommitted
 )
 
 func (r *FetchRequest) encode(pe packetEncoder) (err error) {
diff --git a/vendor/gopkg.in/Shopify/sarama.v1/fetch_response.go b/vendor/gopkg.in/Shopify/sarama.v1/fetch_response.go
index 9df99c1..3afc187 100644
--- a/vendor/gopkg.in/Shopify/sarama.v1/fetch_response.go
+++ b/vendor/gopkg.in/Shopify/sarama.v1/fetch_response.go
@@ -1,6 +1,7 @@
 package sarama
 
 import (
+	"sort"
 	"time"
 )
 
@@ -185,6 +186,17 @@
 	return pe.pop()
 }
 
+func (b *FetchResponseBlock) getAbortedTransactions() []*AbortedTransaction {
+	// I can't find any doc that guarantee the field `fetchResponse.AbortedTransactions` is ordered
+	// plus Java implementation use a PriorityQueue based on `FirstOffset`. I guess we have to order it ourself
+	at := b.AbortedTransactions
+	sort.Slice(
+		at,
+		func(i, j int) bool { return at[i].FirstOffset < at[j].FirstOffset },
+	)
+	return at
+}
+
 type FetchResponse struct {
 	Blocks        map[string]map[int32]*FetchResponseBlock
 	ThrottleTime  time.Duration
@@ -385,6 +397,65 @@
 	batch.addRecord(rec)
 }
 
+// AddRecordBatchWithTimestamp is similar to AddRecordWithTimestamp
+// But instead of appending 1 record to a batch, it append a new batch containing 1 record to the fetchResponse
+// Since transaction are handled on batch level (the whole batch is either committed or aborted), use this to test transactions
+func (r *FetchResponse) AddRecordBatchWithTimestamp(topic string, partition int32, key, value Encoder, offset int64, producerID int64, isTransactional bool, timestamp time.Time) {
+	frb := r.getOrCreateBlock(topic, partition)
+	kb, vb := encodeKV(key, value)
+
+	records := newDefaultRecords(&RecordBatch{Version: 2, LogAppendTime: r.LogAppendTime, FirstTimestamp: timestamp, MaxTimestamp: r.Timestamp})
+	batch := &RecordBatch{
+		Version:         2,
+		LogAppendTime:   r.LogAppendTime,
+		FirstTimestamp:  timestamp,
+		MaxTimestamp:    r.Timestamp,
+		FirstOffset:     offset,
+		LastOffsetDelta: 0,
+		ProducerID:      producerID,
+		IsTransactional: isTransactional,
+	}
+	rec := &Record{Key: kb, Value: vb, OffsetDelta: 0, TimestampDelta: timestamp.Sub(batch.FirstTimestamp)}
+	batch.addRecord(rec)
+	records.RecordBatch = batch
+
+	frb.RecordsSet = append(frb.RecordsSet, &records)
+}
+
+func (r *FetchResponse) AddControlRecordWithTimestamp(topic string, partition int32, offset int64, producerID int64, recordType ControlRecordType, timestamp time.Time) {
+	frb := r.getOrCreateBlock(topic, partition)
+
+	// batch
+	batch := &RecordBatch{
+		Version:         2,
+		LogAppendTime:   r.LogAppendTime,
+		FirstTimestamp:  timestamp,
+		MaxTimestamp:    r.Timestamp,
+		FirstOffset:     offset,
+		LastOffsetDelta: 0,
+		ProducerID:      producerID,
+		IsTransactional: true,
+		Control:         true,
+	}
+
+	// records
+	records := newDefaultRecords(nil)
+	records.RecordBatch = batch
+
+	// record
+	crAbort := ControlRecord{
+		Version: 0,
+		Type:    recordType,
+	}
+	crKey := &realEncoder{raw: make([]byte, 4)}
+	crValue := &realEncoder{raw: make([]byte, 6)}
+	crAbort.encode(crKey, crValue)
+	rec := &Record{Key: ByteEncoder(crKey.raw), Value: ByteEncoder(crValue.raw), OffsetDelta: 0, TimestampDelta: timestamp.Sub(batch.FirstTimestamp)}
+	batch.addRecord(rec)
+
+	frb.RecordsSet = append(frb.RecordsSet, &records)
+}
+
 func (r *FetchResponse) AddMessage(topic string, partition int32, key, value Encoder, offset int64) {
 	r.AddMessageWithTimestamp(topic, partition, key, value, offset, time.Time{}, 0)
 }
@@ -393,6 +464,15 @@
 	r.AddRecordWithTimestamp(topic, partition, key, value, offset, time.Time{})
 }
 
+func (r *FetchResponse) AddRecordBatch(topic string, partition int32, key, value Encoder, offset int64, producerID int64, isTransactional bool) {
+	r.AddRecordBatchWithTimestamp(topic, partition, key, value, offset, producerID, isTransactional, time.Time{})
+}
+
+func (r *FetchResponse) AddControlRecord(topic string, partition int32, offset int64, producerID int64, recordType ControlRecordType) {
+	// define controlRecord key and value
+	r.AddControlRecordWithTimestamp(topic, partition, offset, producerID, recordType, time.Time{})
+}
+
 func (r *FetchResponse) SetLastOffsetDelta(topic string, partition int32, offset int32) {
 	frb := r.getOrCreateBlock(topic, partition)
 	if len(frb.RecordsSet) == 0 {
diff --git a/vendor/gopkg.in/Shopify/sarama.v1/find_coordinator_request.go b/vendor/gopkg.in/Shopify/sarama.v1/find_coordinator_request.go
index 0ab5cb5..ff2ad20 100644
--- a/vendor/gopkg.in/Shopify/sarama.v1/find_coordinator_request.go
+++ b/vendor/gopkg.in/Shopify/sarama.v1/find_coordinator_request.go
@@ -3,8 +3,8 @@
 type CoordinatorType int8
 
 const (
-	CoordinatorGroup       CoordinatorType = 0
-	CoordinatorTransaction CoordinatorType = 1
+	CoordinatorGroup CoordinatorType = iota
+	CoordinatorTransaction
 )
 
 type FindCoordinatorRequest struct {
diff --git a/vendor/gopkg.in/Shopify/sarama.v1/go.mod b/vendor/gopkg.in/Shopify/sarama.v1/go.mod
index 3715129..8c45155 100644
--- a/vendor/gopkg.in/Shopify/sarama.v1/go.mod
+++ b/vendor/gopkg.in/Shopify/sarama.v1/go.mod
@@ -1,13 +1,24 @@
 module github.com/Shopify/sarama
 
 require (
-	github.com/DataDog/zstd v1.3.5
+	github.com/DataDog/zstd v1.3.6-0.20190409195224-796139022798
 	github.com/Shopify/toxiproxy v2.1.4+incompatible
 	github.com/davecgh/go-spew v1.1.1
 	github.com/eapache/go-resiliency v1.1.0
 	github.com/eapache/go-xerial-snappy v0.0.0-20180814174437-776d5712da21
 	github.com/eapache/queue v1.1.0
-	github.com/golang/snappy v0.0.0-20180518054509-2e65f85255db // indirect
-	github.com/pierrec/lz4 v2.0.5+incompatible
+	github.com/golang/snappy v0.0.1 // indirect
+	github.com/hashicorp/go-uuid v1.0.1 // indirect
+	github.com/jcmturner/gofork v0.0.0-20190328161633-dc7c13fece03
+	github.com/pierrec/lz4 v0.0.0-20190327172049-315a67e90e41
 	github.com/rcrowley/go-metrics v0.0.0-20181016184325-3113b8401b8a
+	github.com/stretchr/testify v1.3.0
+	github.com/xdg/scram v0.0.0-20180814205039-7eeb5667e42c
+	github.com/xdg/stringprep v1.0.0 // indirect
+	golang.org/x/crypto v0.0.0-20190404164418-38d8ce5564a5 // indirect
+	golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3
+	gopkg.in/jcmturner/aescts.v1 v1.0.1 // indirect
+	gopkg.in/jcmturner/dnsutils.v1 v1.0.1 // indirect
+	gopkg.in/jcmturner/gokrb5.v7 v7.2.3
+	gopkg.in/jcmturner/rpc.v1 v1.1.0 // indirect
 )
diff --git a/vendor/gopkg.in/Shopify/sarama.v1/go.sum b/vendor/gopkg.in/Shopify/sarama.v1/go.sum
index 58e2e91..4dbc6d2 100644
--- a/vendor/gopkg.in/Shopify/sarama.v1/go.sum
+++ b/vendor/gopkg.in/Shopify/sarama.v1/go.sum
@@ -1,7 +1,8 @@
-github.com/DataDog/zstd v1.3.5 h1:DtpNbljikUepEPD16hD4LvIcmhnhdLTiW/5pHgbmp14=
-github.com/DataDog/zstd v1.3.5/go.mod h1:1jcaCB/ufaK+sKp1NBhlGmpz41jOoPQ35bpF36t7BBo=
+github.com/DataDog/zstd v1.3.6-0.20190409195224-796139022798 h1:2T/jmrHeTezcCM58lvEQXs0UpQJCo5SoGAcg+mbSTIg=
+github.com/DataDog/zstd v1.3.6-0.20190409195224-796139022798/go.mod h1:1jcaCB/ufaK+sKp1NBhlGmpz41jOoPQ35bpF36t7BBo=
 github.com/Shopify/toxiproxy v2.1.4+incompatible h1:TKdv8HiTLgE5wdJuEML90aBgNWsokNbMijUGhmcoBJc=
 github.com/Shopify/toxiproxy v2.1.4+incompatible/go.mod h1:OXgGpZ6Cli1/URJOF1DMxUHB2q5Ap20/P/eIdh4G0pI=
+github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/eapache/go-resiliency v1.1.0 h1:1NtRmCAqadE2FN4ZcN6g90TP3uk8cg9rn9eNK2197aU=
@@ -10,9 +11,41 @@
 github.com/eapache/go-xerial-snappy v0.0.0-20180814174437-776d5712da21/go.mod h1:+020luEh2TKB4/GOp8oxxtq0Daoen/Cii55CzbTV6DU=
 github.com/eapache/queue v1.1.0 h1:YOEu7KNc61ntiQlcEeUIoDTJ2o8mQznoNvUhiigpIqc=
 github.com/eapache/queue v1.1.0/go.mod h1:6eCeP0CKFpHLu8blIFXhExK/dRa7WDZfr6jVFPTqq+I=
-github.com/golang/snappy v0.0.0-20180518054509-2e65f85255db h1:woRePGFeVFfLKN/pOkfl+p/TAqKOfFu+7KPlMVpok/w=
-github.com/golang/snappy v0.0.0-20180518054509-2e65f85255db/go.mod h1:/XxbfmMg8lxefKM7IXC3fBNl/7bRcc72aCRzEWrmP2Q=
-github.com/pierrec/lz4 v2.0.5+incompatible h1:2xWsjqPFWcplujydGg4WmhC/6fZqK42wMM8aXeqhl0I=
-github.com/pierrec/lz4 v2.0.5+incompatible/go.mod h1:pdkljMzZIN41W+lC3N2tnIh5sFi+IEE17M5jbnwPHcY=
+github.com/golang/snappy v0.0.1 h1:Qgr9rKW7uDUkrbSmQeiDsGa8SjGyCOGtuasMWwvp2P4=
+github.com/golang/snappy v0.0.1/go.mod h1:/XxbfmMg8lxefKM7IXC3fBNl/7bRcc72aCRzEWrmP2Q=
+github.com/hashicorp/go-uuid v1.0.1 h1:fv1ep09latC32wFoVwnqcnKJGnMSdBanPczbHAYm1BE=
+github.com/hashicorp/go-uuid v1.0.1/go.mod h1:6SBZvOh/SIDV7/2o3Jml5SYk/TvGqwFJ/bN7x4byOro=
+github.com/jcmturner/gofork v0.0.0-20190328161633-dc7c13fece03 h1:FUwcHNlEqkqLjLBdCp5PRlCFijNjvcYANOZXzCfXwCM=
+github.com/jcmturner/gofork v0.0.0-20190328161633-dc7c13fece03/go.mod h1:MK8+TM0La+2rjBD4jE12Kj1pCCxK7d2LK/UM3ncEo0o=
+github.com/pierrec/lz4 v0.0.0-20190327172049-315a67e90e41 h1:GeinFsrjWz97fAxVUEd748aV0cYL+I6k44gFJTCVvpU=
+github.com/pierrec/lz4 v0.0.0-20190327172049-315a67e90e41/go.mod h1:3/3N9NVKO0jef7pBehbT1qWhCMrIgbYNnFAZCqQ5LRc=
+github.com/pkg/profile v1.2.1/go.mod h1:hJw3o1OdXxsrSjjVksARp5W95eeEaEfptyVZyv6JUPA=
+github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
+github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/rcrowley/go-metrics v0.0.0-20181016184325-3113b8401b8a h1:9ZKAASQSHhDYGoxY8uLVpewe1GDZ2vu2Tr/vTdVAkFQ=
 github.com/rcrowley/go-metrics v0.0.0-20181016184325-3113b8401b8a/go.mod h1:bCqnVzQkZxMG4s8nGwiZ5l3QUCyqpo9Y+/ZMZ9VjZe4=
+github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
+github.com/stretchr/testify v1.3.0 h1:TivCn/peBQ7UY8ooIcPgZFpTNSz0Q2U6UrFlUfqbe0Q=
+github.com/stretchr/testify v1.3.0/go.mod h1:M5WIy9Dh21IEIfnGCwXGc5bZfKNJtfHm1UVUgZn+9EI=
+github.com/xdg/scram v0.0.0-20180814205039-7eeb5667e42c h1:u40Z8hqBAAQyv+vATcGgV0YCnDjqSL7/q/JyPhhJSPk=
+github.com/xdg/scram v0.0.0-20180814205039-7eeb5667e42c/go.mod h1:lB8K/P019DLNhemzwFU4jHLhdvlE6uDZjXFejJXr49I=
+github.com/xdg/stringprep v1.0.0 h1:d9X0esnoa3dFsV0FG35rAT0RIhYFlPq7MiP+DW89La0=
+github.com/xdg/stringprep v1.0.0/go.mod h1:Jhud4/sHMO4oL310DaZAKk9ZaJ08SJfe+sJh0HrGL1Y=
+golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2 h1:VklqNMn3ovrHsnt90PveolxSbWFaJdECFbxSq0Mqo2M=
+golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
+golang.org/x/crypto v0.0.0-20190404164418-38d8ce5564a5 h1:bselrhR0Or1vomJZC8ZIjWtbDmn9OYFLX5Ik9alpJpE=
+golang.org/x/crypto v0.0.0-20190404164418-38d8ce5564a5/go.mod h1:WFFai1msRO1wXaEeE5yQxYXgSfI8pQAWXbQop6sCtWE=
+golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3 h1:0GoQqolDA55aaLxZyTzK/Y2ePZzZTUrRacwib7cNsYQ=
+golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
+golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
+golang.org/x/sys v0.0.0-20190403152447-81d4e9dc473e/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/text v0.3.0 h1:g61tztE5qeGQ89tm6NTjjM9VPIm088od1l6aSorWRWg=
+golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
+gopkg.in/jcmturner/aescts.v1 v1.0.1 h1:cVVZBK2b1zY26haWB4vbBiZrfFQnfbTVrE3xZq6hrEw=
+gopkg.in/jcmturner/aescts.v1 v1.0.1/go.mod h1:nsR8qBOg+OucoIW+WMhB3GspUQXq9XorLnQb9XtvcOo=
+gopkg.in/jcmturner/dnsutils.v1 v1.0.1 h1:cIuC1OLRGZrld+16ZJvvZxVJeKPsvd5eUIvxfoN5hSM=
+gopkg.in/jcmturner/dnsutils.v1 v1.0.1/go.mod h1:m3v+5svpVOhtFAP/wSz+yzh4Mc0Fg7eRhxkJMWSIz9Q=
+gopkg.in/jcmturner/gokrb5.v7 v7.2.3 h1:hHMV/yKPwMnJhPuPx7pH2Uw/3Qyf+thJYlisUc44010=
+gopkg.in/jcmturner/gokrb5.v7 v7.2.3/go.mod h1:l8VISx+WGYp+Fp7KRbsiUuXTTOnxIc3Tuvyavf11/WM=
+gopkg.in/jcmturner/rpc.v1 v1.1.0 h1:QHIUxTX1ISuAv9dD2wJ9HWQVuWDX/Zc0PfeC2tjc4rU=
+gopkg.in/jcmturner/rpc.v1 v1.1.0/go.mod h1:YIdkC4XfD6GXbzje11McwsDuOlZQSb9W4vfLvuNnlv8=
diff --git a/vendor/gopkg.in/Shopify/sarama.v1/gssapi_kerberos.go b/vendor/gopkg.in/Shopify/sarama.v1/gssapi_kerberos.go
new file mode 100644
index 0000000..49b632d
--- /dev/null
+++ b/vendor/gopkg.in/Shopify/sarama.v1/gssapi_kerberos.go
@@ -0,0 +1,257 @@
+package sarama
+
+import (
+	"encoding/binary"
+	"fmt"
+	"github.com/jcmturner/gofork/encoding/asn1"
+	"gopkg.in/jcmturner/gokrb5.v7/asn1tools"
+	"gopkg.in/jcmturner/gokrb5.v7/gssapi"
+	"gopkg.in/jcmturner/gokrb5.v7/iana/chksumtype"
+	"gopkg.in/jcmturner/gokrb5.v7/iana/keyusage"
+	"gopkg.in/jcmturner/gokrb5.v7/messages"
+	"gopkg.in/jcmturner/gokrb5.v7/types"
+	"io"
+	"strings"
+	"time"
+)
+
+const (
+	TOK_ID_KRB_AP_REQ   = 256
+	GSS_API_GENERIC_TAG = 0x60
+	KRB5_USER_AUTH      = 1
+	KRB5_KEYTAB_AUTH    = 2
+	GSS_API_INITIAL     = 1
+	GSS_API_VERIFY      = 2
+	GSS_API_FINISH      = 3
+)
+
+type GSSAPIConfig struct {
+	AuthType           int
+	KeyTabPath         string
+	KerberosConfigPath string
+	ServiceName        string
+	Username           string
+	Password           string
+	Realm              string
+}
+
+type GSSAPIKerberosAuth struct {
+	Config                *GSSAPIConfig
+	ticket                messages.Ticket
+	encKey                types.EncryptionKey
+	NewKerberosClientFunc func(config *GSSAPIConfig) (KerberosClient, error)
+	step                  int
+}
+
+type KerberosClient interface {
+	Login() error
+	GetServiceTicket(spn string) (messages.Ticket, types.EncryptionKey, error)
+	Domain() string
+	CName() types.PrincipalName
+	Destroy()
+}
+
+/*
+*
+* Appends length in big endian before payload, and send it to kafka
+*
+ */
+
+func (krbAuth *GSSAPIKerberosAuth) writePackage(broker *Broker, payload []byte) (int, error) {
+	length := len(payload)
+	finalPackage := make([]byte, length+4) //4 byte length header + payload
+	copy(finalPackage[4:], payload)
+	binary.BigEndian.PutUint32(finalPackage, uint32(length))
+	bytes, err := broker.conn.Write(finalPackage)
+	if err != nil {
+		return bytes, err
+	}
+	return bytes, nil
+}
+
+/*
+*
+* Read length (4 bytes) and then read the payload
+*
+ */
+
+func (krbAuth *GSSAPIKerberosAuth) readPackage(broker *Broker) ([]byte, int, error) {
+	bytesRead := 0
+	lengthInBytes := make([]byte, 4)
+	bytes, err := io.ReadFull(broker.conn, lengthInBytes)
+	if err != nil {
+		return nil, bytesRead, err
+	}
+	bytesRead += bytes
+	payloadLength := binary.BigEndian.Uint32(lengthInBytes)
+	payloadBytes := make([]byte, payloadLength)         // buffer for read..
+	bytes, err = io.ReadFull(broker.conn, payloadBytes) // read bytes
+	if err != nil {
+		return payloadBytes, bytesRead, err
+	}
+	bytesRead += bytes
+	return payloadBytes, bytesRead, nil
+}
+
+func (krbAuth *GSSAPIKerberosAuth) newAuthenticatorChecksum() []byte {
+	a := make([]byte, 24)
+	flags := []int{gssapi.ContextFlagInteg, gssapi.ContextFlagConf}
+	binary.LittleEndian.PutUint32(a[:4], 16)
+	for _, i := range flags {
+		f := binary.LittleEndian.Uint32(a[20:24])
+		f |= uint32(i)
+		binary.LittleEndian.PutUint32(a[20:24], f)
+	}
+	return a
+}
+
+/*
+*
+* Construct Kerberos AP_REQ package, conforming to RFC-4120
+* https://tools.ietf.org/html/rfc4120#page-84
+*
+ */
+func (krbAuth *GSSAPIKerberosAuth) createKrb5Token(
+	domain string, cname types.PrincipalName,
+	ticket messages.Ticket,
+	sessionKey types.EncryptionKey) ([]byte, error) {
+	auth, err := types.NewAuthenticator(domain, cname)
+	if err != nil {
+		return nil, err
+	}
+	auth.Cksum = types.Checksum{
+		CksumType: chksumtype.GSSAPI,
+		Checksum:  krbAuth.newAuthenticatorChecksum(),
+	}
+	APReq, err := messages.NewAPReq(
+		ticket,
+		sessionKey,
+		auth,
+	)
+	if err != nil {
+		return nil, err
+	}
+	aprBytes := make([]byte, 2)
+	binary.BigEndian.PutUint16(aprBytes, TOK_ID_KRB_AP_REQ)
+	tb, err := APReq.Marshal()
+	if err != nil {
+		return nil, err
+	}
+	aprBytes = append(aprBytes, tb...)
+	return aprBytes, nil
+}
+
+/*
+*
+*	Append the GSS-API header to the payload, conforming to RFC-2743
+*	Section 3.1, Mechanism-Independent Token Format
+*
+*	https://tools.ietf.org/html/rfc2743#page-81
+*
+*	GSSAPIHeader + <specific mechanism payload>
+*
+ */
+func (krbAuth *GSSAPIKerberosAuth) appendGSSAPIHeader(payload []byte) ([]byte, error) {
+	oidBytes, err := asn1.Marshal(gssapi.OID(gssapi.OIDKRB5))
+	if err != nil {
+		return nil, err
+	}
+	tkoLengthBytes := asn1tools.MarshalLengthBytes(len(oidBytes) + len(payload))
+	GSSHeader := append([]byte{GSS_API_GENERIC_TAG}, tkoLengthBytes...)
+	GSSHeader = append(GSSHeader, oidBytes...)
+	GSSPackage := append(GSSHeader, payload...)
+	return GSSPackage, nil
+}
+
+func (krbAuth *GSSAPIKerberosAuth) initSecContext(bytes []byte, kerberosClient KerberosClient) ([]byte, error) {
+	switch krbAuth.step {
+	case GSS_API_INITIAL:
+		aprBytes, err := krbAuth.createKrb5Token(
+			kerberosClient.Domain(),
+			kerberosClient.CName(),
+			krbAuth.ticket,
+			krbAuth.encKey)
+		if err != nil {
+			return nil, err
+		}
+		krbAuth.step = GSS_API_VERIFY
+		return krbAuth.appendGSSAPIHeader(aprBytes)
+	case GSS_API_VERIFY:
+		wrapTokenReq := gssapi.WrapToken{}
+		if err := wrapTokenReq.Unmarshal(bytes, true); err != nil {
+			return nil, err
+		}
+		// Validate response.
+		isValid, err := wrapTokenReq.Verify(krbAuth.encKey, keyusage.GSSAPI_ACCEPTOR_SEAL)
+		if !isValid {
+			return nil, err
+		}
+
+		wrapTokenResponse, err := gssapi.NewInitiatorWrapToken(wrapTokenReq.Payload, krbAuth.encKey)
+		if err != nil {
+			return nil, err
+		}
+		krbAuth.step = GSS_API_FINISH
+		return wrapTokenResponse.Marshal()
+	}
+	return nil, nil
+}
+
+/* This does the handshake for authorization */
+func (krbAuth *GSSAPIKerberosAuth) Authorize(broker *Broker) error {
+
+	kerberosClient, err := krbAuth.NewKerberosClientFunc(krbAuth.Config)
+	if err != nil {
+		Logger.Printf("Kerberos client error: %s", err)
+		return err
+	}
+
+	err = kerberosClient.Login()
+	if err != nil {
+		Logger.Printf("Kerberos client error: %s", err)
+		return err
+	}
+	// Construct SPN using serviceName and host
+	// SPN format: <SERVICE>/<FQDN>
+
+	host := strings.SplitN(broker.addr, ":", 2)[0] // Strip port part
+	spn := fmt.Sprintf("%s/%s", broker.conf.Net.SASL.GSSAPI.ServiceName, host)
+
+	ticket, encKey, err := kerberosClient.GetServiceTicket(spn)
+
+	if err != nil {
+		Logger.Printf("Error getting Kerberos service ticket : %s", err)
+		return err
+	}
+	krbAuth.ticket = ticket
+	krbAuth.encKey = encKey
+	krbAuth.step = GSS_API_INITIAL
+	var receivedBytes []byte = nil
+	defer kerberosClient.Destroy()
+	for {
+		packBytes, err := krbAuth.initSecContext(receivedBytes, kerberosClient)
+		if err != nil {
+			Logger.Printf("Error while performing GSSAPI Kerberos Authentication: %s\n", err)
+			return err
+		}
+		requestTime := time.Now()
+		bytesWritten, err := krbAuth.writePackage(broker, packBytes)
+		if err != nil {
+			Logger.Printf("Error while performing GSSAPI Kerberos Authentication: %s\n", err)
+			return err
+		}
+		broker.updateOutgoingCommunicationMetrics(bytesWritten)
+		if krbAuth.step == GSS_API_VERIFY {
+			var bytesRead = 0
+			receivedBytes, bytesRead, err = krbAuth.readPackage(broker)
+			requestLatency := time.Since(requestTime)
+			broker.updateIncomingCommunicationMetrics(bytesRead, requestLatency)
+			if err != nil {
+				Logger.Printf("Error while performing GSSAPI Kerberos Authentication: %s\n", err)
+				return err
+			}
+		} else if krbAuth.step == GSS_API_FINISH {
+			return nil
+		}
+	}
+}
diff --git a/vendor/gopkg.in/Shopify/sarama.v1/kerberos_client.go b/vendor/gopkg.in/Shopify/sarama.v1/kerberos_client.go
new file mode 100644
index 0000000..91b998f
--- /dev/null
+++ b/vendor/gopkg.in/Shopify/sarama.v1/kerberos_client.go
@@ -0,0 +1,51 @@
+package sarama
+
+import (
+	krb5client "gopkg.in/jcmturner/gokrb5.v7/client"
+	krb5config "gopkg.in/jcmturner/gokrb5.v7/config"
+	"gopkg.in/jcmturner/gokrb5.v7/keytab"
+	"gopkg.in/jcmturner/gokrb5.v7/types"
+)
+
+type KerberosGoKrb5Client struct {
+	krb5client.Client
+}
+
+func (c *KerberosGoKrb5Client) Domain() string {
+	return c.Credentials.Domain()
+}
+
+func (c *KerberosGoKrb5Client) CName() types.PrincipalName {
+	return c.Credentials.CName()
+}
+
+/*
+*
+* Create kerberos client used to obtain TGT and TGS tokens
+* used gokrb5 library, which is a pure go kerberos client with
+* some GSS-API capabilities, and SPNEGO support. Kafka does not use SPNEGO
+* it uses pure Kerberos 5 solution (RFC-4121 and RFC-4120).
+*
+ */
+func NewKerberosClient(config *GSSAPIConfig) (KerberosClient, error) {
+	cfg, err := krb5config.Load(config.KerberosConfigPath)
+	if err != nil {
+		return nil, err
+	}
+	return createClient(config, cfg)
+}
+
+func createClient(config *GSSAPIConfig, cfg *krb5config.Config) (KerberosClient, error) {
+	var client *krb5client.Client
+	if config.AuthType == KRB5_KEYTAB_AUTH {
+		kt, err := keytab.Load(config.KeyTabPath)
+		if err != nil {
+			return nil, err
+		}
+		client = krb5client.NewClientWithKeytab(config.Username, config.Realm, kt, cfg)
+	} else {
+		client = krb5client.NewClientWithPassword(config.Username,
+			config.Realm, config.Password, cfg)
+	}
+	return &KerberosGoKrb5Client{*client}, nil
+}
diff --git a/vendor/gopkg.in/Shopify/sarama.v1/length_field.go b/vendor/gopkg.in/Shopify/sarama.v1/length_field.go
index da199a7..7d864f6 100644
--- a/vendor/gopkg.in/Shopify/sarama.v1/length_field.go
+++ b/vendor/gopkg.in/Shopify/sarama.v1/length_field.go
@@ -1,6 +1,9 @@
 package sarama
 
-import "encoding/binary"
+import (
+	"encoding/binary"
+	"sync"
+)
 
 // LengthField implements the PushEncoder and PushDecoder interfaces for calculating 4-byte lengths.
 type lengthField struct {
@@ -8,6 +11,20 @@
 	length      int32
 }
 
+var lengthFieldPool = sync.Pool{}
+
+func acquireLengthField() *lengthField {
+	val := lengthFieldPool.Get()
+	if val != nil {
+		return val.(*lengthField)
+	}
+	return &lengthField{}
+}
+
+func releaseLengthField(m *lengthField) {
+	lengthFieldPool.Put(m)
+}
+
 func (l *lengthField) decode(pd packetDecoder) error {
 	var err error
 	l.length, err = pd.getInt32()
diff --git a/vendor/gopkg.in/Shopify/sarama.v1/message.go b/vendor/gopkg.in/Shopify/sarama.v1/message.go
index f64c79b..7c54748 100644
--- a/vendor/gopkg.in/Shopify/sarama.v1/message.go
+++ b/vendor/gopkg.in/Shopify/sarama.v1/message.go
@@ -5,37 +5,44 @@
 	"time"
 )
 
-// The lowest 3 bits contain the compression codec used for the message
-const compressionCodecMask int8 = 0x07
+const (
+	//CompressionNone no compression
+	CompressionNone CompressionCodec = iota
+	//CompressionGZIP compression using GZIP
+	CompressionGZIP
+	//CompressionSnappy compression using snappy
+	CompressionSnappy
+	//CompressionLZ4 compression using LZ4
+	CompressionLZ4
+	//CompressionZSTD compression using ZSTD
+	CompressionZSTD
 
-// Bit 3 set for "LogAppend" timestamps
-const timestampTypeMask = 0x08
+	// The lowest 3 bits contain the compression codec used for the message
+	compressionCodecMask int8 = 0x07
+
+	// Bit 3 set for "LogAppend" timestamps
+	timestampTypeMask = 0x08
+
+	// CompressionLevelDefault is the constant to use in CompressionLevel
+	// to have the default compression level for any codec. The value is picked
+	// that we don't use any existing compression levels.
+	CompressionLevelDefault = -1000
+)
 
 // CompressionCodec represents the various compression codecs recognized by Kafka in messages.
 type CompressionCodec int8
 
-const (
-	CompressionNone   CompressionCodec = 0
-	CompressionGZIP   CompressionCodec = 1
-	CompressionSnappy CompressionCodec = 2
-	CompressionLZ4    CompressionCodec = 3
-	CompressionZSTD   CompressionCodec = 4
-)
-
 func (cc CompressionCodec) String() string {
 	return []string{
 		"none",
 		"gzip",
 		"snappy",
 		"lz4",
+		"zstd",
 	}[int(cc)]
 }
 
-// CompressionLevelDefault is the constant to use in CompressionLevel
-// to have the default compression level for any codec. The value is picked
-// that we don't use any existing compression levels.
-const CompressionLevelDefault = -1000
-
+//Message is a kafka message type
 type Message struct {
 	Codec            CompressionCodec // codec used to compress the message contents
 	CompressionLevel int              // compression level
@@ -96,7 +103,10 @@
 }
 
 func (m *Message) decode(pd packetDecoder) (err error) {
-	err = pd.push(newCRC32Field(crcIEEE))
+	crc32Decoder := acquireCrc32Field(crcIEEE)
+	defer releaseCrc32Field(crc32Decoder)
+
+	err = pd.push(crc32Decoder)
 	if err != nil {
 		return err
 	}
diff --git a/vendor/gopkg.in/Shopify/sarama.v1/message_set.go b/vendor/gopkg.in/Shopify/sarama.v1/message_set.go
index 600c7c4..6523ec2 100644
--- a/vendor/gopkg.in/Shopify/sarama.v1/message_set.go
+++ b/vendor/gopkg.in/Shopify/sarama.v1/message_set.go
@@ -29,7 +29,10 @@
 		return err
 	}
 
-	if err = pd.push(&lengthField{}); err != nil {
+	lengthDecoder := acquireLengthField()
+	defer releaseLengthField(lengthDecoder)
+
+	if err = pd.push(lengthDecoder); err != nil {
 		return err
 	}
 
diff --git a/vendor/gopkg.in/Shopify/sarama.v1/metadata_request.go b/vendor/gopkg.in/Shopify/sarama.v1/metadata_request.go
index 17dc428..1b590d3 100644
--- a/vendor/gopkg.in/Shopify/sarama.v1/metadata_request.go
+++ b/vendor/gopkg.in/Shopify/sarama.v1/metadata_request.go
@@ -37,15 +37,8 @@
 	if err != nil {
 		return err
 	}
-	if size < 0 {
-		return nil
-	} else {
-		topicCount := size
-		if topicCount == 0 {
-			return nil
-		}
-
-		r.Topics = make([]string, topicCount)
+	if size > 0 {
+		r.Topics = make([]string, size)
 		for i := range r.Topics {
 			topic, err := pd.getString()
 			if err != nil {
diff --git a/vendor/gopkg.in/Shopify/sarama.v1/metadata_response.go b/vendor/gopkg.in/Shopify/sarama.v1/metadata_response.go
index c402d05..b2d532e 100644
--- a/vendor/gopkg.in/Shopify/sarama.v1/metadata_response.go
+++ b/vendor/gopkg.in/Shopify/sarama.v1/metadata_response.go
@@ -296,7 +296,7 @@
 	return tmatch
 }
 
-func (r *MetadataResponse) AddTopicPartition(topic string, partition, brokerID int32, replicas, isr []int32, err KError) {
+func (r *MetadataResponse) AddTopicPartition(topic string, partition, brokerID int32, replicas, isr []int32, offline []int32, err KError) {
 	tmatch := r.AddTopic(topic, ErrNoError)
 	var pmatch *PartitionMetadata
 
@@ -316,6 +316,7 @@
 	pmatch.Leader = brokerID
 	pmatch.Replicas = replicas
 	pmatch.Isr = isr
+	pmatch.OfflineReplicas = offline
 	pmatch.Err = err
 
 }
diff --git a/vendor/gopkg.in/Shopify/sarama.v1/metrics.go b/vendor/gopkg.in/Shopify/sarama.v1/metrics.go
index 4869708..90e5a87 100644
--- a/vendor/gopkg.in/Shopify/sarama.v1/metrics.go
+++ b/vendor/gopkg.in/Shopify/sarama.v1/metrics.go
@@ -28,14 +28,6 @@
 	return fmt.Sprintf(name+"-for-broker-%d", broker.ID())
 }
 
-func getOrRegisterBrokerMeter(name string, broker *Broker, r metrics.Registry) metrics.Meter {
-	return metrics.GetOrRegisterMeter(getMetricNameForBroker(name, broker), r)
-}
-
-func getOrRegisterBrokerHistogram(name string, broker *Broker, r metrics.Registry) metrics.Histogram {
-	return getOrRegisterHistogram(getMetricNameForBroker(name, broker), r)
-}
-
 func getMetricNameForTopic(name string, topic string) string {
 	// Convert dot to _ since reporters like Graphite typically use dot to represent hierarchy
 	// cf. KAFKA-1902 and KAFKA-2337
diff --git a/vendor/gopkg.in/Shopify/sarama.v1/mockbroker.go b/vendor/gopkg.in/Shopify/sarama.v1/mockbroker.go
index 55ef1e2..4ed46a6 100644
--- a/vendor/gopkg.in/Shopify/sarama.v1/mockbroker.go
+++ b/vendor/gopkg.in/Shopify/sarama.v1/mockbroker.go
@@ -18,6 +18,8 @@
 	expectationTimeout = 500 * time.Millisecond
 )
 
+type GSSApiHandlerFunc func([]byte) []byte
+
 type requestHandlerFunc func(req *request) (res encoder)
 
 // RequestNotifierFunc is invoked when a mock broker processes a request successfully
@@ -49,18 +51,19 @@
 // It is not necessary to prefix message length or correlation ID to your
 // response bytes, the server does that automatically as a convenience.
 type MockBroker struct {
-	brokerID     int32
-	port         int32
-	closing      chan none
-	stopper      chan none
-	expectations chan encoder
-	listener     net.Listener
-	t            TestReporter
-	latency      time.Duration
-	handler      requestHandlerFunc
-	notifier     RequestNotifierFunc
-	history      []RequestResponse
-	lock         sync.Mutex
+	brokerID      int32
+	port          int32
+	closing       chan none
+	stopper       chan none
+	expectations  chan encoder
+	listener      net.Listener
+	t             TestReporter
+	latency       time.Duration
+	handler       requestHandlerFunc
+	notifier      RequestNotifierFunc
+	history       []RequestResponse
+	lock          sync.Mutex
+	gssApiHandler GSSApiHandlerFunc
 }
 
 // RequestResponse represents a Request/Response pair processed by MockBroker.
@@ -173,6 +176,43 @@
 	Logger.Printf("*** mockbroker/%d: listener closed, err=%v", b.BrokerID(), err)
 }
 
+func (b *MockBroker) SetGSSAPIHandler(handler GSSApiHandlerFunc) {
+	b.gssApiHandler = handler
+}
+
+func (b *MockBroker) readToBytes(r io.Reader) ([]byte, error) {
+	var (
+		bytesRead   int
+		lengthBytes = make([]byte, 4)
+	)
+
+	if _, err := io.ReadFull(r, lengthBytes); err != nil {
+		return nil, err
+	}
+
+	bytesRead += len(lengthBytes)
+	length := int32(binary.BigEndian.Uint32(lengthBytes))
+
+	if length <= 4 || length > MaxRequestSize {
+		return nil, PacketDecodingError{fmt.Sprintf("message of length %d too large or too small", length)}
+	}
+
+	encodedReq := make([]byte, length)
+	if _, err := io.ReadFull(r, encodedReq); err != nil {
+		return nil, err
+	}
+
+	bytesRead += len(encodedReq)
+
+	fullBytes := append(lengthBytes, encodedReq...)
+
+	return fullBytes, nil
+}
+
+func (b *MockBroker) isGSSAPI(buffer []byte) bool {
+	return buffer[4] == 0x60 || bytes.Equal(buffer[4:6], []byte{0x05, 0x04})
+}
+
 func (b *MockBroker) handleRequests(conn net.Conn, idx int, wg *sync.WaitGroup) {
 	defer wg.Done()
 	defer func() {
@@ -192,59 +232,92 @@
 	}()
 
 	resHeader := make([]byte, 8)
+	var bytesWritten int
+	var bytesRead int
 	for {
-		req, bytesRead, err := decodeRequest(conn)
+
+		buffer, err := b.readToBytes(conn)
 		if err != nil {
-			Logger.Printf("*** mockbroker/%d/%d: invalid request: err=%+v, %+v", b.brokerID, idx, err, spew.Sdump(req))
+			Logger.Printf("*** mockbroker/%d/%d: invalid request: err=%+v, %+v", b.brokerID, idx, err, spew.Sdump(buffer))
 			b.serverError(err)
 			break
 		}
 
-		if b.latency > 0 {
-			time.Sleep(b.latency)
-		}
+		bytesWritten = 0
+		if !b.isGSSAPI(buffer) {
 
-		b.lock.Lock()
-		res := b.handler(req)
-		b.history = append(b.history, RequestResponse{req.body, res})
-		b.lock.Unlock()
-
-		if res == nil {
-			Logger.Printf("*** mockbroker/%d/%d: ignored %v", b.brokerID, idx, spew.Sdump(req))
-			continue
-		}
-		Logger.Printf("*** mockbroker/%d/%d: served %v -> %v", b.brokerID, idx, req, res)
-
-		encodedRes, err := encode(res, nil)
-		if err != nil {
-			b.serverError(err)
-			break
-		}
-		if len(encodedRes) == 0 {
-			b.lock.Lock()
-			if b.notifier != nil {
-				b.notifier(bytesRead, 0)
+			req, br, err := decodeRequest(bytes.NewReader(buffer))
+			bytesRead = br
+			if err != nil {
+				Logger.Printf("*** mockbroker/%d/%d: invalid request: err=%+v, %+v", b.brokerID, idx, err, spew.Sdump(req))
+				b.serverError(err)
+				break
 			}
-			b.lock.Unlock()
-			continue
-		}
 
-		binary.BigEndian.PutUint32(resHeader, uint32(len(encodedRes)+4))
-		binary.BigEndian.PutUint32(resHeader[4:], uint32(req.correlationID))
-		if _, err = conn.Write(resHeader); err != nil {
-			b.serverError(err)
-			break
-		}
-		if _, err = conn.Write(encodedRes); err != nil {
-			b.serverError(err)
-			break
+			if b.latency > 0 {
+				time.Sleep(b.latency)
+			}
+
+			b.lock.Lock()
+			res := b.handler(req)
+			b.history = append(b.history, RequestResponse{req.body, res})
+			b.lock.Unlock()
+
+			if res == nil {
+				Logger.Printf("*** mockbroker/%d/%d: ignored %v", b.brokerID, idx, spew.Sdump(req))
+				continue
+			}
+			Logger.Printf("*** mockbroker/%d/%d: served %v -> %v", b.brokerID, idx, req, res)
+
+			encodedRes, err := encode(res, nil)
+			if err != nil {
+				b.serverError(err)
+				break
+			}
+			if len(encodedRes) == 0 {
+				b.lock.Lock()
+				if b.notifier != nil {
+					b.notifier(bytesRead, 0)
+				}
+				b.lock.Unlock()
+				continue
+			}
+
+			binary.BigEndian.PutUint32(resHeader, uint32(len(encodedRes)+4))
+			binary.BigEndian.PutUint32(resHeader[4:], uint32(req.correlationID))
+			if _, err = conn.Write(resHeader); err != nil {
+				b.serverError(err)
+				break
+			}
+			if _, err = conn.Write(encodedRes); err != nil {
+				b.serverError(err)
+				break
+			}
+			bytesWritten = len(resHeader) + len(encodedRes)
+
+		} else {
+			// GSSAPI is not part of kafka protocol, but is supported for authentication proposes.
+			// Don't support history for this kind of request as is only used for test GSSAPI authentication mechanism
+			b.lock.Lock()
+			res := b.gssApiHandler(buffer)
+			b.lock.Unlock()
+			if res == nil {
+				Logger.Printf("*** mockbroker/%d/%d: ignored %v", b.brokerID, idx, spew.Sdump(buffer))
+				continue
+			}
+			if _, err = conn.Write(res); err != nil {
+				b.serverError(err)
+				break
+			}
+			bytesWritten = len(res)
 		}
 
 		b.lock.Lock()
 		if b.notifier != nil {
-			b.notifier(bytesRead, len(resHeader)+len(encodedRes))
+			b.notifier(bytesRead, bytesWritten)
 		}
 		b.lock.Unlock()
+
 	}
 	Logger.Printf("*** mockbroker/%d/%d: connection closed, err=%v", b.BrokerID(), idx, err)
 }
diff --git a/vendor/gopkg.in/Shopify/sarama.v1/mockkerberos.go b/vendor/gopkg.in/Shopify/sarama.v1/mockkerberos.go
new file mode 100644
index 0000000..affeb2d
--- /dev/null
+++ b/vendor/gopkg.in/Shopify/sarama.v1/mockkerberos.go
@@ -0,0 +1,123 @@
+package sarama
+
+import (
+	"encoding/binary"
+	"encoding/hex"
+	"gopkg.in/jcmturner/gokrb5.v7/credentials"
+	"gopkg.in/jcmturner/gokrb5.v7/gssapi"
+	"gopkg.in/jcmturner/gokrb5.v7/iana/keyusage"
+	"gopkg.in/jcmturner/gokrb5.v7/messages"
+	"gopkg.in/jcmturner/gokrb5.v7/types"
+)
+
+type KafkaGSSAPIHandler struct {
+	client         *MockKerberosClient
+	badResponse    bool
+	badKeyChecksum bool
+}
+
+func (h *KafkaGSSAPIHandler) MockKafkaGSSAPI(buffer []byte) []byte {
+	// Default payload used for verify
+	err := h.client.Login() // Mock client construct keys when login
+	if err != nil {
+		return nil
+	}
+	if h.badResponse { // Returns trash
+		return []byte{0x00, 0x00, 0x00, 0x01, 0xAD}
+	}
+
+	var pack = gssapi.WrapToken{
+		Flags:     KRB5_USER_AUTH,
+		EC:        12,
+		RRC:       0,
+		SndSeqNum: 3398292281,
+		Payload:   []byte{0x11, 0x00}, // 1100
+	}
+	// Compute checksum
+	if h.badKeyChecksum {
+		pack.CheckSum = []byte{0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF}
+	} else {
+		err = pack.SetCheckSum(h.client.ASRep.DecryptedEncPart.Key, keyusage.GSSAPI_ACCEPTOR_SEAL)
+		if err != nil {
+			return nil
+		}
+	}
+
+	packBytes, err := pack.Marshal()
+	if err != nil {
+		return nil
+	}
+	lenBytes := len(packBytes)
+	response := make([]byte, lenBytes+4)
+	copy(response[4:], packBytes)
+	binary.BigEndian.PutUint32(response, uint32(lenBytes))
+	return response
+}
+
+type MockKerberosClient struct {
+	asReqBytes  string
+	asRepBytes  string
+	ASRep       messages.ASRep
+	credentials *credentials.Credentials
+	mockError   error
+	errorStage  string
+}
+
+func (c *MockKerberosClient) Login() error {
+	if c.errorStage == "login" && c.mockError != nil {
+		return c.mockError
+	}
+	c.asRepBytes = "6b8202e9308202e5a003020105a10302010ba22b30293027a103020113a220041e301c301aa003020112a1131b114" +
+		"558414d504c452e434f4d636c69656e74a30d1b0b4558414d504c452e434f4da4133011a003020101a10a30081b06636c69656e7" +
+		"4a5820156618201523082014ea003020105a10d1b0b4558414d504c452e434f4da220301ea003020102a11730151b066b7262746" +
+		"7741b0b4558414d504c452e434f4da382011430820110a003020112a103020101a28201020481ffdb9891175d106818e61008c51" +
+		"d0b3462bca92f3bf9d4cfa82de4c4d7aff9994ec87c573e3a3d54dcb2bb79618c76f2bf4a3d006f90d5bdbd049bc18f48be39203" +
+		"549ca02acaf63f292b12404f9b74c34b83687119d8f56552ccc0c50ebee2a53bb114c1b4619bb1d5d31f0f49b4d40a08a9b4c046" +
+		"2e1398d0b648be1c0e50c552ad16e1d8d8e74263dd0bf0ec591e4797dfd40a9a1be4ae830d03a306e053fd7586fef84ffc5e4a83" +
+		"7c3122bf3e6a40fe87e84019f6283634461b955712b44a5f7386c278bff94ec2c2dc0403247e29c2450e853471ceababf9b8911f" +
+		"997f2e3010b046d2c49eb438afb0f4c210821e80d4ffa4c9521eb895dcd68610b3feaa682012c30820128a003020112a282011f0" +
+		"482011bce73cbce3f1dd17661c412005f0f2257c756fe8e98ff97e6ec24b7bab66e5fd3a3827aeeae4757af0c6e892948122d8b2" +
+		"03c8df48df0ef5d142d0e416d688f11daa0fcd63d96bdd431d02b8e951c664eeff286a2be62383d274a04016d5f0e141da58cb86" +
+		"331de64063062f4f885e8e9ce5b181ca2fdc67897c5995e0ae1ae0c171a64493ff7bd91bc6d89cd4fce1e2b3ea0a10e34b0d5eda" +
+		"aa38ee727b50c5632ed1d2f2b457908e616178d0d80b72af209fb8ac9dbaa1768fa45931392b36b6d8c12400f8ded2efaa0654d0" +
+		"da1db966e8b5aab4706c800f95d559664646041fdb38b411c62fc0fbe0d25083a28562b0e1c8df16e62e9d5626b0addee489835f" +
+		"eedb0f26c05baa596b69b17f47920aa64b29dc77cfcc97ba47885"
+	apRepBytes, err := hex.DecodeString(c.asRepBytes)
+	if err != nil {
+		return err
+	}
+	err = c.ASRep.Unmarshal(apRepBytes)
+	if err != nil {
+		return err
+	}
+	c.credentials = credentials.New("client", "EXAMPLE.COM").WithPassword("qwerty")
+	_, err = c.ASRep.DecryptEncPart(c.credentials)
+	if err != nil {
+		return err
+	}
+	return nil
+}
+
+func (c *MockKerberosClient) GetServiceTicket(spn string) (messages.Ticket, types.EncryptionKey, error) {
+	if c.errorStage == "service_ticket" && c.mockError != nil {
+		return messages.Ticket{}, types.EncryptionKey{}, c.mockError
+	}
+	return c.ASRep.Ticket, c.ASRep.DecryptedEncPart.Key, nil
+}
+
+func (c *MockKerberosClient) Domain() string {
+	return "EXAMPLE.COM"
+}
+func (c *MockKerberosClient) CName() types.PrincipalName {
+	var p = types.PrincipalName{
+		NameType: KRB5_USER_AUTH,
+		NameString: []string{
+			"kafka",
+			"kafka",
+		},
+	}
+	return p
+}
+func (c *MockKerberosClient) Destroy() {
+	// Do nothing.
+}
diff --git a/vendor/gopkg.in/Shopify/sarama.v1/mockresponses.go b/vendor/gopkg.in/Shopify/sarama.v1/mockresponses.go
index 348c223..c78f0ac 100644
--- a/vendor/gopkg.in/Shopify/sarama.v1/mockresponses.go
+++ b/vendor/gopkg.in/Shopify/sarama.v1/mockresponses.go
@@ -2,6 +2,7 @@
 
 import (
 	"fmt"
+	"strings"
 )
 
 // TestReporter has methods matching go's testing.T to avoid importing
@@ -177,7 +178,7 @@
 
 	// Generate set of replicas
 	replicas := []int32{}
-
+	offlineReplicas := []int32{}
 	for _, brokerID := range mmr.brokers {
 		replicas = append(replicas, brokerID)
 	}
@@ -185,14 +186,14 @@
 	if len(metadataRequest.Topics) == 0 {
 		for topic, partitions := range mmr.leaders {
 			for partition, brokerID := range partitions {
-				metadataResponse.AddTopicPartition(topic, partition, brokerID, replicas, replicas, ErrNoError)
+				metadataResponse.AddTopicPartition(topic, partition, brokerID, replicas, replicas, offlineReplicas, ErrNoError)
 			}
 		}
 		return metadataResponse
 	}
 	for _, topic := range metadataRequest.Topics {
 		for partition, brokerID := range mmr.leaders[topic] {
-			metadataResponse.AddTopicPartition(topic, partition, brokerID, replicas, replicas, ErrNoError)
+			metadataResponse.AddTopicPartition(topic, partition, brokerID, replicas, replicas, offlineReplicas, ErrNoError)
 		}
 	}
 	return metadataResponse
@@ -573,6 +574,7 @@
 // MockOffsetFetchResponse is a `OffsetFetchResponse` builder.
 type MockOffsetFetchResponse struct {
 	offsets map[string]map[string]map[int32]*OffsetFetchResponseBlock
+	error   KError
 	t       TestReporter
 }
 
@@ -598,15 +600,25 @@
 	return mr
 }
 
+func (mr *MockOffsetFetchResponse) SetError(kerror KError) *MockOffsetFetchResponse {
+	mr.error = kerror
+	return mr
+}
+
 func (mr *MockOffsetFetchResponse) For(reqBody versionedDecoder) encoder {
 	req := reqBody.(*OffsetFetchRequest)
 	group := req.ConsumerGroup
-	res := &OffsetFetchResponse{}
+	res := &OffsetFetchResponse{Version: req.Version}
+
 	for topic, partitions := range mr.offsets[group] {
 		for partition, block := range partitions {
 			res.AddBlock(topic, partition, block)
 		}
 	}
+
+	if res.Version >= 2 {
+		res.Err = mr.error
+	}
 	return res
 }
 
@@ -620,10 +632,20 @@
 
 func (mr *MockCreateTopicsResponse) For(reqBody versionedDecoder) encoder {
 	req := reqBody.(*CreateTopicsRequest)
-	res := &CreateTopicsResponse{}
+	res := &CreateTopicsResponse{
+		Version: req.Version,
+	}
 	res.TopicErrors = make(map[string]*TopicError)
 
-	for topic, _ := range req.TopicDetails {
+	for topic := range req.TopicDetails {
+		if res.Version >= 1 && strings.HasPrefix(topic, "_") {
+			msg := "insufficient permissions to create topic with reserved prefix"
+			res.TopicErrors[topic] = &TopicError{
+				Err:    ErrTopicAuthorizationFailed,
+				ErrMsg: &msg,
+			}
+			continue
+		}
 		res.TopicErrors[topic] = &TopicError{Err: ErrNoError}
 	}
 	return res
@@ -661,7 +683,15 @@
 	res := &CreatePartitionsResponse{}
 	res.TopicPartitionErrors = make(map[string]*TopicPartitionError)
 
-	for topic, _ := range req.TopicPartitions {
+	for topic := range req.TopicPartitions {
+		if strings.HasPrefix(topic, "_") {
+			msg := "insufficient permissions to create partition on topic with reserved prefix"
+			res.TopicPartitionErrors[topic] = &TopicPartitionError{
+				Err:    ErrTopicAuthorizationFailed,
+				ErrMsg: &msg,
+			}
+			continue
+		}
 		res.TopicPartitionErrors[topic] = &TopicPartitionError{Err: ErrNoError}
 	}
 	return res
@@ -682,7 +712,7 @@
 
 	for topic, deleteRecordRequestTopic := range req.Topics {
 		partitions := make(map[int32]*DeleteRecordsResponsePartition)
-		for partition, _ := range deleteRecordRequestTopic.PartitionOffsets {
+		for partition := range deleteRecordRequestTopic.PartitionOffsets {
 			partitions[partition] = &DeleteRecordsResponsePartition{Err: ErrNoError}
 		}
 		res.Topics[topic] = &DeleteRecordsResponseTopic{Partitions: partitions}
@@ -866,3 +896,26 @@
 	}
 	return res
 }
+
+type MockDeleteGroupsResponse struct {
+	deletedGroups []string
+}
+
+func NewMockDeleteGroupsRequest(t TestReporter) *MockDeleteGroupsResponse {
+	return &MockDeleteGroupsResponse{}
+}
+
+func (m *MockDeleteGroupsResponse) SetDeletedGroups(groups []string) *MockDeleteGroupsResponse {
+	m.deletedGroups = groups
+	return m
+}
+
+func (m *MockDeleteGroupsResponse) For(reqBody versionedDecoder) encoder {
+	resp := &DeleteGroupsResponse{
+		GroupErrorCodes: map[string]KError{},
+	}
+	for _, group := range m.deletedGroups {
+		resp.GroupErrorCodes[group] = ErrNoError
+	}
+	return resp
+}
diff --git a/vendor/gopkg.in/Shopify/sarama.v1/offset_commit_request.go b/vendor/gopkg.in/Shopify/sarama.v1/offset_commit_request.go
index 1ec583e..5732ed9 100644
--- a/vendor/gopkg.in/Shopify/sarama.v1/offset_commit_request.go
+++ b/vendor/gopkg.in/Shopify/sarama.v1/offset_commit_request.go
@@ -200,11 +200,11 @@
 func (r *OffsetCommitRequest) Offset(topic string, partitionID int32) (int64, string, error) {
 	partitions := r.blocks[topic]
 	if partitions == nil {
-		return 0, "", errors.New("No such offset")
+		return 0, "", errors.New("no such offset")
 	}
 	block := partitions[partitionID]
 	if block == nil {
-		return 0, "", errors.New("No such offset")
+		return 0, "", errors.New("no such offset")
 	}
 	return block.offset, block.metadata, nil
 }
diff --git a/vendor/gopkg.in/Shopify/sarama.v1/offset_manager.go b/vendor/gopkg.in/Shopify/sarama.v1/offset_manager.go
index 2432f7b..923972f 100644
--- a/vendor/gopkg.in/Shopify/sarama.v1/offset_manager.go
+++ b/vendor/gopkg.in/Shopify/sarama.v1/offset_manager.go
@@ -333,7 +333,6 @@
 				pom.handleError(err)
 			case ErrOffsetsLoadInProgress:
 				// nothing wrong but we didn't commit, we'll get it next time round
-				break
 			case ErrUnknownTopicOrPartition:
 				// let the user know *and* try redispatching - if topic-auto-create is
 				// enabled, redispatching should trigger a metadata req and create the
@@ -576,6 +575,6 @@
 
 func (pom *partitionOffsetManager) release() {
 	pom.releaseOnce.Do(func() {
-		go close(pom.errors)
+		close(pom.errors)
 	})
 }
diff --git a/vendor/gopkg.in/Shopify/sarama.v1/packet_decoder.go b/vendor/gopkg.in/Shopify/sarama.v1/packet_decoder.go
index 74805cc..9be854c 100644
--- a/vendor/gopkg.in/Shopify/sarama.v1/packet_decoder.go
+++ b/vendor/gopkg.in/Shopify/sarama.v1/packet_decoder.go
@@ -27,6 +27,7 @@
 	remaining() int
 	getSubset(length int) (packetDecoder, error)
 	peek(offset, length int) (packetDecoder, error) // similar to getSubset, but it doesn't advance the offset
+	peekInt8(offset int) (int8, error)              // similar to peek, but just one byte
 
 	// Stacks, see PushDecoder
 	push(in pushDecoder) error
diff --git a/vendor/gopkg.in/Shopify/sarama.v1/produce_set.go b/vendor/gopkg.in/Shopify/sarama.v1/produce_set.go
index 4b42d9c..bba0f7e 100644
--- a/vendor/gopkg.in/Shopify/sarama.v1/produce_set.go
+++ b/vendor/gopkg.in/Shopify/sarama.v1/produce_set.go
@@ -81,7 +81,7 @@
 
 	if ps.parent.conf.Version.IsAtLeast(V0_11_0_0) {
 		if ps.parent.conf.Producer.Idempotent && msg.sequenceNumber < set.recordsToSend.RecordBatch.FirstSequence {
-			return errors.New("Assertion failed: Message out of sequence added to a batch")
+			return errors.New("assertion failed: message out of sequence added to a batch")
 		}
 		// We are being conservative here to avoid having to prep encode the record
 		size += maximumRecordOverhead
diff --git a/vendor/gopkg.in/Shopify/sarama.v1/real_decoder.go b/vendor/gopkg.in/Shopify/sarama.v1/real_decoder.go
index 23045e7..085cbb3 100644
--- a/vendor/gopkg.in/Shopify/sarama.v1/real_decoder.go
+++ b/vendor/gopkg.in/Shopify/sarama.v1/real_decoder.go
@@ -290,6 +290,14 @@
 	return &realDecoder{raw: rd.raw[off : off+length]}, nil
 }
 
+func (rd *realDecoder) peekInt8(offset int) (int8, error) {
+	const byteLen = 1
+	if rd.remaining() < offset+byteLen {
+		return -1, ErrInsufficientData
+	}
+	return int8(rd.raw[rd.off+offset]), nil
+}
+
 // stacks
 
 func (rd *realDecoder) push(in pushDecoder) error {
diff --git a/vendor/gopkg.in/Shopify/sarama.v1/record.go b/vendor/gopkg.in/Shopify/sarama.v1/record.go
index cded308..cdccfe3 100644
--- a/vendor/gopkg.in/Shopify/sarama.v1/record.go
+++ b/vendor/gopkg.in/Shopify/sarama.v1/record.go
@@ -6,10 +6,12 @@
 )
 
 const (
+	isTransactionalMask   = 0x10
 	controlMask           = 0x20
 	maximumRecordOverhead = 5*binary.MaxVarintLen32 + binary.MaxVarintLen64 + 1
 )
 
+//RecordHeader stores key and value for a record header
 type RecordHeader struct {
 	Key   []byte
 	Value []byte
@@ -33,15 +35,16 @@
 	return nil
 }
 
+//Record is kafka record type
 type Record struct {
+	Headers []*RecordHeader
+
 	Attributes     int8
 	TimestampDelta time.Duration
 	OffsetDelta    int64
 	Key            []byte
 	Value          []byte
-	Headers        []*RecordHeader
-
-	length varintLengthField
+	length         varintLengthField
 }
 
 func (r *Record) encode(pe packetEncoder) error {
diff --git a/vendor/gopkg.in/Shopify/sarama.v1/record_batch.go b/vendor/gopkg.in/Shopify/sarama.v1/record_batch.go
index a36f7e6..c653763 100644
--- a/vendor/gopkg.in/Shopify/sarama.v1/record_batch.go
+++ b/vendor/gopkg.in/Shopify/sarama.v1/record_batch.go
@@ -45,11 +45,16 @@
 	FirstSequence         int32
 	Records               []*Record
 	PartialTrailingRecord bool
+	IsTransactional       bool
 
 	compressedRecords []byte
 	recordsLen        int // uncompressed records size
 }
 
+func (b *RecordBatch) LastOffset() int64 {
+	return b.FirstOffset + int64(b.LastOffsetDelta)
+}
+
 func (b *RecordBatch) encode(pe packetEncoder) error {
 	if b.Version != 2 {
 		return PacketEncodingError{fmt.Sprintf("unsupported compression codec (%d)", b.Codec)}
@@ -111,7 +116,10 @@
 		return err
 	}
 
-	if err = pd.push(&crc32Field{polynomial: crcCastagnoli}); err != nil {
+	crc32Decoder := acquireCrc32Field(crcCastagnoli)
+	defer releaseCrc32Field(crc32Decoder)
+
+	if err = pd.push(crc32Decoder); err != nil {
 		return err
 	}
 
@@ -122,6 +130,7 @@
 	b.Codec = CompressionCodec(int8(attributes) & compressionCodecMask)
 	b.Control = attributes&controlMask == controlMask
 	b.LogAppendTime = attributes&timestampTypeMask == timestampTypeMask
+	b.IsTransactional = attributes&isTransactionalMask == isTransactionalMask
 
 	if b.LastOffsetDelta, err = pd.getInt32(); err != nil {
 		return err
@@ -205,6 +214,9 @@
 	if b.LogAppendTime {
 		attr |= timestampTypeMask
 	}
+	if b.IsTransactional {
+		attr |= isTransactionalMask
+	}
 	return attr
 }
 
diff --git a/vendor/gopkg.in/Shopify/sarama.v1/records.go b/vendor/gopkg.in/Shopify/sarama.v1/records.go
index 192f592..98160c7 100644
--- a/vendor/gopkg.in/Shopify/sarama.v1/records.go
+++ b/vendor/gopkg.in/Shopify/sarama.v1/records.go
@@ -185,10 +185,20 @@
 }
 
 func magicValue(pd packetDecoder) (int8, error) {
-	dec, err := pd.peek(magicOffset, magicLength)
-	if err != nil {
-		return 0, err
+	return pd.peekInt8(magicOffset)
+}
+
+func (r *Records) getControlRecord() (ControlRecord, error) {
+	if r.RecordBatch == nil || len(r.RecordBatch.Records) <= 0 {
+		return ControlRecord{}, fmt.Errorf("cannot get control record, record batch is empty")
 	}
 
-	return dec.getInt8()
+	firstRecord := r.RecordBatch.Records[0]
+	controlRecord := ControlRecord{}
+	err := controlRecord.decode(&realDecoder{raw: firstRecord.Key}, &realDecoder{raw: firstRecord.Value})
+	if err != nil {
+		return ControlRecord{}, err
+	}
+
+	return controlRecord, nil
 }
diff --git a/vendor/gopkg.in/Shopify/sarama.v1/request.go b/vendor/gopkg.in/Shopify/sarama.v1/request.go
index f7eea59..5ed8ca4 100644
--- a/vendor/gopkg.in/Shopify/sarama.v1/request.go
+++ b/vendor/gopkg.in/Shopify/sarama.v1/request.go
@@ -20,51 +20,67 @@
 	body          protocolBody
 }
 
-func (r *request) encode(pe packetEncoder) (err error) {
+func (r *request) encode(pe packetEncoder) error {
 	pe.push(&lengthField{})
 	pe.putInt16(r.body.key())
 	pe.putInt16(r.body.version())
 	pe.putInt32(r.correlationID)
-	err = pe.putString(r.clientID)
+
+	err := pe.putString(r.clientID)
 	if err != nil {
 		return err
 	}
+
 	err = r.body.encode(pe)
 	if err != nil {
 		return err
 	}
+
 	return pe.pop()
 }
 
 func (r *request) decode(pd packetDecoder) (err error) {
-	var key int16
-	if key, err = pd.getInt16(); err != nil {
+	key, err := pd.getInt16()
+	if err != nil {
 		return err
 	}
-	var version int16
-	if version, err = pd.getInt16(); err != nil {
+
+	version, err := pd.getInt16()
+	if err != nil {
 		return err
 	}
-	if r.correlationID, err = pd.getInt32(); err != nil {
+
+	r.correlationID, err = pd.getInt32()
+	if err != nil {
 		return err
 	}
+
 	r.clientID, err = pd.getString()
+	if err != nil {
+		return err
+	}
 
 	r.body = allocateBody(key, version)
 	if r.body == nil {
 		return PacketDecodingError{fmt.Sprintf("unknown request key (%d)", key)}
 	}
+
 	return r.body.decode(pd, version)
 }
 
-func decodeRequest(r io.Reader) (req *request, bytesRead int, err error) {
-	lengthBytes := make([]byte, 4)
+func decodeRequest(r io.Reader) (*request, int, error) {
+	var (
+		bytesRead   int
+		lengthBytes = make([]byte, 4)
+	)
+
 	if _, err := io.ReadFull(r, lengthBytes); err != nil {
 		return nil, bytesRead, err
 	}
-	bytesRead += len(lengthBytes)
 
+	bytesRead += len(lengthBytes)
 	length := int32(binary.BigEndian.Uint32(lengthBytes))
+
 	if length <= 4 || length > MaxRequestSize {
 		return nil, bytesRead, PacketDecodingError{fmt.Sprintf("message of length %d too large or too small", length)}
 	}
@@ -73,12 +89,14 @@
 	if _, err := io.ReadFull(r, encodedReq); err != nil {
 		return nil, bytesRead, err
 	}
+
 	bytesRead += len(encodedReq)
 
-	req = &request{}
+	req := &request{}
 	if err := decode(encodedReq, req); err != nil {
 		return nil, bytesRead, err
 	}
+
 	return req, bytesRead, nil
 }
 
diff --git a/vendor/gopkg.in/Shopify/sarama.v1/response_header.go b/vendor/gopkg.in/Shopify/sarama.v1/response_header.go
index f3f4d27..7a75918 100644
--- a/vendor/gopkg.in/Shopify/sarama.v1/response_header.go
+++ b/vendor/gopkg.in/Shopify/sarama.v1/response_header.go
@@ -2,6 +2,9 @@
 
 import "fmt"
 
+const responseLengthSize = 4
+const correlationIDSize = 4
+
 type responseHeader struct {
 	length        int32
 	correlationID int32
diff --git a/vendor/gopkg.in/Shopify/sarama.v1/sarama.go b/vendor/gopkg.in/Shopify/sarama.v1/sarama.go
index 7d5dc60..1e0277a 100644
--- a/vendor/gopkg.in/Shopify/sarama.v1/sarama.go
+++ b/vendor/gopkg.in/Shopify/sarama.v1/sarama.go
@@ -10,10 +10,7 @@
 depend on the configured value of `Producer.RequiredAcks`. There are configurations where a message acknowledged by the
 SyncProducer can still sometimes be lost.
 
-To consume messages, use the Consumer. Note that Sarama's Consumer implementation does not currently support automatic
-consumer-group rebalancing and offset tracking. For Zookeeper-based tracking (Kafka 0.8.2 and earlier), the
-https://github.com/wvanbergen/kafka library builds on Sarama to add this support. For Kafka-based tracking (Kafka 0.9
-and later), the https://github.com/bsm/sarama-cluster library builds on Sarama to add this support.
+To consume messages, use Consumer or Consumer-Group API.
 
 For lower-level needs, the Broker and Request/Response objects permit precise control over each connection
 and message sent on the wire; the Client provides higher-level metadata management that is shared between
@@ -61,6 +58,14 @@
 	| compression-ratio-for-topic-<topic>       | histogram  | Distribution of the compression ratio times 100 of record batches for a given topic  |
 	+-------------------------------------------+------------+--------------------------------------------------------------------------------------+
 
+Consumer related metrics:
+
+	+-------------------------------------------+------------+--------------------------------------------------------------------------------------+
+	| Name                                      | Type       | Description                                                                          |
+	+-------------------------------------------+------------+--------------------------------------------------------------------------------------+
+	| consumer-batch-size                       | histogram  | Distribution of the number of messages in a batch                                    |
+	+-------------------------------------------+------------+--------------------------------------------------------------------------------------+
+
 */
 package sarama
 
@@ -69,10 +74,29 @@
 	"log"
 )
 
-// Logger is the instance of a StdLogger interface that Sarama writes connection
-// management events to. By default it is set to discard all log messages via ioutil.Discard,
-// but you can set it to redirect wherever you want.
-var Logger StdLogger = log.New(ioutil.Discard, "[Sarama] ", log.LstdFlags)
+var (
+	// Logger is the instance of a StdLogger interface that Sarama writes connection
+	// management events to. By default it is set to discard all log messages via ioutil.Discard,
+	// but you can set it to redirect wherever you want.
+	Logger StdLogger = log.New(ioutil.Discard, "[Sarama] ", log.LstdFlags)
+
+	// PanicHandler is called for recovering from panics spawned internally to the library (and thus
+	// not recoverable by the caller's goroutine). Defaults to nil, which means panics are not recovered.
+	PanicHandler func(interface{})
+
+	// MaxRequestSize is the maximum size (in bytes) of any request that Sarama will attempt to send. Trying
+	// to send a request larger than this will result in an PacketEncodingError. The default of 100 MiB is aligned
+	// with Kafka's default `socket.request.max.bytes`, which is the largest request the broker will attempt
+	// to process.
+	MaxRequestSize int32 = 100 * 1024 * 1024
+
+	// MaxResponseSize is the maximum size (in bytes) of any response that Sarama will attempt to parse. If
+	// a broker returns a response message larger than this value, Sarama will return a PacketDecodingError to
+	// protect the client from running out of memory. Please note that brokers do not have any natural limit on
+	// the size of responses they send. In particular, they can send arbitrarily large fetch responses to consumers
+	// (see https://issues.apache.org/jira/browse/KAFKA-2063).
+	MaxResponseSize int32 = 100 * 1024 * 1024
+)
 
 // StdLogger is used to log error messages.
 type StdLogger interface {
@@ -80,20 +104,3 @@
 	Printf(format string, v ...interface{})
 	Println(v ...interface{})
 }
-
-// PanicHandler is called for recovering from panics spawned internally to the library (and thus
-// not recoverable by the caller's goroutine). Defaults to nil, which means panics are not recovered.
-var PanicHandler func(interface{})
-
-// MaxRequestSize is the maximum size (in bytes) of any request that Sarama will attempt to send. Trying
-// to send a request larger than this will result in an PacketEncodingError. The default of 100 MiB is aligned
-// with Kafka's default `socket.request.max.bytes`, which is the largest request the broker will attempt
-// to process.
-var MaxRequestSize int32 = 100 * 1024 * 1024
-
-// MaxResponseSize is the maximum size (in bytes) of any response that Sarama will attempt to parse. If
-// a broker returns a response message larger than this value, Sarama will return a PacketDecodingError to
-// protect the client from running out of memory. Please note that brokers do not have any natural limit on
-// the size of responses they send. In particular, they can send arbitrarily large fetch responses to consumers
-// (see https://issues.apache.org/jira/browse/KAFKA-2063).
-var MaxResponseSize int32 = 100 * 1024 * 1024
diff --git a/vendor/gopkg.in/Shopify/sarama.v1/utils.go b/vendor/gopkg.in/Shopify/sarama.v1/utils.go
index 7dcbf03..7c815cd 100644
--- a/vendor/gopkg.in/Shopify/sarama.v1/utils.go
+++ b/vendor/gopkg.in/Shopify/sarama.v1/utils.go
@@ -159,6 +159,8 @@
 	V2_0_0_0  = newKafkaVersion(2, 0, 0, 0)
 	V2_0_1_0  = newKafkaVersion(2, 0, 1, 0)
 	V2_1_0_0  = newKafkaVersion(2, 1, 0, 0)
+	V2_2_0_0  = newKafkaVersion(2, 2, 0, 0)
+	V2_3_0_0  = newKafkaVersion(2, 3, 0, 0)
 
 	SupportedVersions = []KafkaVersion{
 		V0_8_2_0,
@@ -181,11 +183,14 @@
 		V2_0_0_0,
 		V2_0_1_0,
 		V2_1_0_0,
+		V2_2_0_0,
+		V2_3_0_0,
 	}
 	MinVersion = V0_8_2_0
-	MaxVersion = V2_1_0_0
+	MaxVersion = V2_3_0_0
 )
 
+//ParseKafkaVersion parses and returns kafka version or error from a string
 func ParseKafkaVersion(s string) (KafkaVersion, error) {
 	if len(s) < 5 {
 		return MinVersion, fmt.Errorf("invalid version `%s`", s)