This update provides:
1)  workaround around the build failures. In
summary, it forces the download of some packages during the build
process.
2) update the set of packages that should go inside the vendor
directory
3) Update the dockerfile to use go 1.10

Change-Id: I2bfd090ce0f25b0c10aa214755ae2da7e5384d60
diff --git a/vendor/github.com/grpc-ecosystem/go-grpc-prometheus/.gitignore b/vendor/github.com/grpc-ecosystem/go-grpc-prometheus/.gitignore
new file mode 100644
index 0000000..2233cff
--- /dev/null
+++ b/vendor/github.com/grpc-ecosystem/go-grpc-prometheus/.gitignore
@@ -0,0 +1,201 @@
+#vendor
+vendor/
+
+# Created by .ignore support plugin (hsz.mobi)
+coverage.txt
+### Go template
+# Compiled Object files, Static and Dynamic libs (Shared Objects)
+*.o
+*.a
+*.so
+
+# Folders
+_obj
+_test
+
+# Architecture specific extensions/prefixes
+*.[568vq]
+[568vq].out
+
+*.cgo1.go
+*.cgo2.c
+_cgo_defun.c
+_cgo_gotypes.go
+_cgo_export.*
+
+_testmain.go
+
+*.exe
+*.test
+*.prof
+### Windows template
+# Windows image file caches
+Thumbs.db
+ehthumbs.db
+
+# Folder config file
+Desktop.ini
+
+# Recycle Bin used on file shares
+$RECYCLE.BIN/
+
+# Windows Installer files
+*.cab
+*.msi
+*.msm
+*.msp
+
+# Windows shortcuts
+*.lnk
+### Kate template
+# Swap Files #
+.*.kate-swp
+.swp.*
+### SublimeText template
+# cache files for sublime text
+*.tmlanguage.cache
+*.tmPreferences.cache
+*.stTheme.cache
+
+# workspace files are user-specific
+*.sublime-workspace
+
+# project files should be checked into the repository, unless a significant
+# proportion of contributors will probably not be using SublimeText
+# *.sublime-project
+
+# sftp configuration file
+sftp-config.json
+### Linux template
+*~
+
+# temporary files which can be created if a process still has a handle open of a deleted file
+.fuse_hidden*
+
+# KDE directory preferences
+.directory
+
+# Linux trash folder which might appear on any partition or disk
+.Trash-*
+### JetBrains template
+# Covers JetBrains IDEs: IntelliJ, RubyMine, PhpStorm, AppCode, PyCharm, CLion, Android Studio and Webstorm
+# Reference: https://intellij-support.jetbrains.com/hc/en-us/articles/206544839
+
+# User-specific stuff:
+.idea
+.idea/tasks.xml
+.idea/dictionaries
+.idea/vcs.xml
+.idea/jsLibraryMappings.xml
+
+# Sensitive or high-churn files:
+.idea/dataSources.ids
+.idea/dataSources.xml
+.idea/dataSources.local.xml
+.idea/sqlDataSources.xml
+.idea/dynamic.xml
+.idea/uiDesigner.xml
+
+# Gradle:
+.idea/gradle.xml
+.idea/libraries
+
+# Mongo Explorer plugin:
+.idea/mongoSettings.xml
+
+## File-based project format:
+*.iws
+
+## Plugin-specific files:
+
+# IntelliJ
+/out/
+
+# mpeltonen/sbt-idea plugin
+.idea_modules/
+
+# JIRA plugin
+atlassian-ide-plugin.xml
+
+# Crashlytics plugin (for Android Studio and IntelliJ)
+com_crashlytics_export_strings.xml
+crashlytics.properties
+crashlytics-build.properties
+fabric.properties
+### Xcode template
+# Xcode
+#
+# gitignore contributors: remember to update Global/Xcode.gitignore, Objective-C.gitignore & Swift.gitignore
+
+## Build generated
+build/
+DerivedData/
+
+## Various settings
+*.pbxuser
+!default.pbxuser
+*.mode1v3
+!default.mode1v3
+*.mode2v3
+!default.mode2v3
+*.perspectivev3
+!default.perspectivev3
+xcuserdata/
+
+## Other
+*.moved-aside
+*.xccheckout
+*.xcscmblueprint
+### Eclipse template
+
+.metadata
+bin/
+tmp/
+*.tmp
+*.bak
+*.swp
+*~.nib
+local.properties
+.settings/
+.loadpath
+.recommenders
+
+# Eclipse Core
+.project
+
+# External tool builders
+.externalToolBuilders/
+
+# Locally stored "Eclipse launch configurations"
+*.launch
+
+# PyDev specific (Python IDE for Eclipse)
+*.pydevproject
+
+# CDT-specific (C/C++ Development Tooling)
+.cproject
+
+# JDT-specific (Eclipse Java Development Tools)
+.classpath
+
+# Java annotation processor (APT)
+.factorypath
+
+# PDT-specific (PHP Development Tools)
+.buildpath
+
+# sbteclipse plugin
+.target
+
+# Tern plugin
+.tern-project
+
+# TeXlipse plugin
+.texlipse
+
+# STS (Spring Tool Suite)
+.springBeans
+
+# Code Recommenders
+.recommenders/
+
diff --git a/vendor/github.com/grpc-ecosystem/go-grpc-prometheus/.travis.yml b/vendor/github.com/grpc-ecosystem/go-grpc-prometheus/.travis.yml
new file mode 100644
index 0000000..2a845b9
--- /dev/null
+++ b/vendor/github.com/grpc-ecosystem/go-grpc-prometheus/.travis.yml
@@ -0,0 +1,25 @@
+sudo: false
+language: go
+# * github.com/grpc/grpc-go still supports go1.6
+#   - When we drop support for go1.6 we can remove golang.org/x/net/context
+#     below as it is part of the Go std library since go1.7
+# * github.com/prometheus/client_golang already requires at least go1.7 since
+#   September 2017
+go:
+  - 1.6.x
+  - 1.7.x
+  - 1.8.x
+  - 1.9.x
+  - 1.10.x
+  - master
+
+install:
+  - go get github.com/prometheus/client_golang/prometheus
+  - go get google.golang.org/grpc
+  - go get golang.org/x/net/context
+  - go get github.com/stretchr/testify
+script:
+ - make test 
+
+after_success:
+  - bash <(curl -s https://codecov.io/bash)
diff --git a/vendor/github.com/grpc-ecosystem/go-grpc-prometheus/CHANGELOG.md b/vendor/github.com/grpc-ecosystem/go-grpc-prometheus/CHANGELOG.md
new file mode 100644
index 0000000..19a8059
--- /dev/null
+++ b/vendor/github.com/grpc-ecosystem/go-grpc-prometheus/CHANGELOG.md
@@ -0,0 +1,24 @@
+# Changelog
+All notable changes to this project will be documented in this file.
+
+The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/)
+and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.html).
+
+## [Unreleased]
+
+## [1.2.0](https://github.com/grpc-ecosystem/go-grpc-prometheus/releases/tag/v1.2.0) - 2018-06-04
+
+### Added
+
+* Provide metrics object as `prometheus.Collector`, for conventional metric registration.
+* Support non-default/global Prometheus registry.
+* Allow configuring counters with `prometheus.CounterOpts`.
+
+### Changed
+
+* Remove usage of deprecated `grpc.Code()`.
+* Remove usage of deprecated `grpc.Errorf` and replace with `status.Errorf`.
+
+---
+
+This changelog was started with version `v1.2.0`, for earlier versions refer to the respective [GitHub releases](https://github.com/grpc-ecosystem/go-grpc-prometheus/releases).
diff --git a/vendor/github.com/grpc-ecosystem/go-grpc-prometheus/LICENSE b/vendor/github.com/grpc-ecosystem/go-grpc-prometheus/LICENSE
new file mode 100644
index 0000000..b2b0650
--- /dev/null
+++ b/vendor/github.com/grpc-ecosystem/go-grpc-prometheus/LICENSE
@@ -0,0 +1,201 @@
+                 Apache License
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+
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diff --git a/vendor/github.com/grpc-ecosystem/go-grpc-prometheus/README.md b/vendor/github.com/grpc-ecosystem/go-grpc-prometheus/README.md
new file mode 100644
index 0000000..499c583
--- /dev/null
+++ b/vendor/github.com/grpc-ecosystem/go-grpc-prometheus/README.md
@@ -0,0 +1,247 @@
+# Go gRPC Interceptors for Prometheus monitoring 
+
+[![Travis Build](https://travis-ci.org/grpc-ecosystem/go-grpc-prometheus.svg)](https://travis-ci.org/grpc-ecosystem/go-grpc-prometheus)
+[![Go Report Card](https://goreportcard.com/badge/github.com/grpc-ecosystem/go-grpc-prometheus)](http://goreportcard.com/report/grpc-ecosystem/go-grpc-prometheus)
+[![GoDoc](http://img.shields.io/badge/GoDoc-Reference-blue.svg)](https://godoc.org/github.com/grpc-ecosystem/go-grpc-prometheus)
+[![SourceGraph](https://sourcegraph.com/github.com/grpc-ecosystem/go-grpc-prometheus/-/badge.svg)](https://sourcegraph.com/github.com/grpc-ecosystem/go-grpc-prometheus/?badge)
+[![codecov](https://codecov.io/gh/grpc-ecosystem/go-grpc-prometheus/branch/master/graph/badge.svg)](https://codecov.io/gh/grpc-ecosystem/go-grpc-prometheus)
+[![Apache 2.0 License](https://img.shields.io/badge/License-Apache%202.0-blue.svg)](LICENSE)
+
+[Prometheus](https://prometheus.io/) monitoring for your [gRPC Go](https://github.com/grpc/grpc-go) servers and clients.
+
+A sister implementation for [gRPC Java](https://github.com/grpc/grpc-java) (same metrics, same semantics) is in [grpc-ecosystem/java-grpc-prometheus](https://github.com/grpc-ecosystem/java-grpc-prometheus).
+
+## Interceptors
+
+[gRPC Go](https://github.com/grpc/grpc-go) recently acquired support for Interceptors, i.e. middleware that is executed
+by a gRPC Server before the request is passed onto the user's application logic. It is a perfect way to implement
+common patterns: auth, logging and... monitoring.
+
+To use Interceptors in chains, please see [`go-grpc-middleware`](https://github.com/mwitkow/go-grpc-middleware).
+
+## Usage
+
+There are two types of interceptors: client-side and server-side. This package provides monitoring Interceptors for both.
+
+### Server-side
+
+```go
+import "github.com/grpc-ecosystem/go-grpc-prometheus"
+...
+    // Initialize your gRPC server's interceptor.
+    myServer := grpc.NewServer(
+        grpc.StreamInterceptor(grpc_prometheus.StreamServerInterceptor),
+        grpc.UnaryInterceptor(grpc_prometheus.UnaryServerInterceptor),
+    )
+    // Register your gRPC service implementations.
+    myservice.RegisterMyServiceServer(s.server, &myServiceImpl{})
+    // After all your registrations, make sure all of the Prometheus metrics are initialized.
+    grpc_prometheus.Register(myServer)
+    // Register Prometheus metrics handler.    
+    http.Handle("/metrics", promhttp.Handler())
+...
+```
+
+### Client-side
+
+```go
+import "github.com/grpc-ecosystem/go-grpc-prometheus"
+...
+   clientConn, err = grpc.Dial(
+       address,
+		   grpc.WithUnaryInterceptor(grpc_prometheus.UnaryClientInterceptor),
+		   grpc.WithStreamInterceptor(grpc_prometheus.StreamClientInterceptor)
+   )
+   client = pb_testproto.NewTestServiceClient(clientConn)
+   resp, err := client.PingEmpty(s.ctx, &myservice.Request{Msg: "hello"})
+...
+```
+
+# Metrics
+
+## Labels
+
+All server-side metrics start with `grpc_server` as Prometheus subsystem name. All client-side metrics start with `grpc_client`. Both of them have mirror-concepts. Similarly all methods
+contain the same rich labels:
+  
+  * `grpc_service` - the [gRPC service](http://www.grpc.io/docs/#defining-a-service) name, which is the combination of protobuf `package` and
+    the `grpc_service` section name. E.g. for `package = mwitkow.testproto` and 
+     `service TestService` the label will be `grpc_service="mwitkow.testproto.TestService"`
+  * `grpc_method` - the name of the method called on the gRPC service. E.g.  
+    `grpc_method="Ping"`
+  * `grpc_type` - the gRPC [type of request](http://www.grpc.io/docs/guides/concepts.html#rpc-life-cycle). 
+    Differentiating between the two is important especially for latency measurements.
+
+     - `unary` is single request, single response RPC
+     - `client_stream` is a multi-request, single response RPC
+     - `server_stream` is a single request, multi-response RPC
+     - `bidi_stream` is a multi-request, multi-response RPC
+    
+
+Additionally for completed RPCs, the following labels are used:
+
+  * `grpc_code` - the human-readable [gRPC status code](https://github.com/grpc/grpc-go/blob/master/codes/codes.go).
+    The list of all statuses is to long, but here are some common ones:
+      
+      - `OK` - means the RPC was successful
+      - `IllegalArgument` - RPC contained bad values
+      - `Internal` - server-side error not disclosed to the clients
+      
+## Counters
+
+The counters and their up to date documentation is in [server_reporter.go](server_reporter.go) and [client_reporter.go](client_reporter.go) 
+the respective Prometheus handler (usually `/metrics`). 
+
+For the purpose of this documentation we will only discuss `grpc_server` metrics. The `grpc_client` ones contain mirror concepts.
+
+For simplicity, let's assume we're tracking a single server-side RPC call of [`mwitkow.testproto.TestService`](examples/testproto/test.proto),
+calling the method `PingList`. The call succeeds and returns 20 messages in the stream.
+
+First, immediately after the server receives the call it will increment the
+`grpc_server_started_total` and start the handling time clock (if histograms are enabled). 
+
+```jsoniq
+grpc_server_started_total{grpc_method="PingList",grpc_service="mwitkow.testproto.TestService",grpc_type="server_stream"} 1
+```
+
+Then the user logic gets invoked. It receives one message from the client containing the request 
+(it's a `server_stream`):
+
+```jsoniq
+grpc_server_msg_received_total{grpc_method="PingList",grpc_service="mwitkow.testproto.TestService",grpc_type="server_stream"} 1
+```
+
+The user logic may return an error, or send multiple messages back to the client. In this case, on 
+each of the 20 messages sent back, a counter will be incremented:
+
+```jsoniq
+grpc_server_msg_sent_total{grpc_method="PingList",grpc_service="mwitkow.testproto.TestService",grpc_type="server_stream"} 20
+```
+
+After the call completes, its status (`OK` or other [gRPC status code](https://github.com/grpc/grpc-go/blob/master/codes/codes.go)) 
+and the relevant call labels increment the `grpc_server_handled_total` counter.
+
+```jsoniq
+grpc_server_handled_total{grpc_code="OK",grpc_method="PingList",grpc_service="mwitkow.testproto.TestService",grpc_type="server_stream"} 1
+```
+
+## Histograms
+
+[Prometheus histograms](https://prometheus.io/docs/concepts/metric_types/#histogram) are a great way
+to measure latency distributions of your RPCs. However, since it is bad practice to have metrics
+of [high cardinality](https://prometheus.io/docs/practices/instrumentation/#do-not-overuse-labels)
+the latency monitoring metrics are disabled by default. To enable them please call the following
+in your server initialization code:
+
+```jsoniq
+grpc_prometheus.EnableHandlingTimeHistogram()
+```
+
+After the call completes, its handling time will be recorded in a [Prometheus histogram](https://prometheus.io/docs/concepts/metric_types/#histogram)
+variable `grpc_server_handling_seconds`. The histogram variable contains three sub-metrics:
+
+ * `grpc_server_handling_seconds_count` - the count of all completed RPCs by status and method 
+ * `grpc_server_handling_seconds_sum` - cumulative time of RPCs by status and method, useful for 
+   calculating average handling times
+ * `grpc_server_handling_seconds_bucket` - contains the counts of RPCs by status and method in respective
+   handling-time buckets. These buckets can be used by Prometheus to estimate SLAs (see [here](https://prometheus.io/docs/practices/histograms/))
+
+The counter values will look as follows:
+
+```jsoniq
+grpc_server_handling_seconds_bucket{grpc_code="OK",grpc_method="PingList",grpc_service="mwitkow.testproto.TestService",grpc_type="server_stream",le="0.005"} 1
+grpc_server_handling_seconds_bucket{grpc_code="OK",grpc_method="PingList",grpc_service="mwitkow.testproto.TestService",grpc_type="server_stream",le="0.01"} 1
+grpc_server_handling_seconds_bucket{grpc_code="OK",grpc_method="PingList",grpc_service="mwitkow.testproto.TestService",grpc_type="server_stream",le="0.025"} 1
+grpc_server_handling_seconds_bucket{grpc_code="OK",grpc_method="PingList",grpc_service="mwitkow.testproto.TestService",grpc_type="server_stream",le="0.05"} 1
+grpc_server_handling_seconds_bucket{grpc_code="OK",grpc_method="PingList",grpc_service="mwitkow.testproto.TestService",grpc_type="server_stream",le="0.1"} 1
+grpc_server_handling_seconds_bucket{grpc_code="OK",grpc_method="PingList",grpc_service="mwitkow.testproto.TestService",grpc_type="server_stream",le="0.25"} 1
+grpc_server_handling_seconds_bucket{grpc_code="OK",grpc_method="PingList",grpc_service="mwitkow.testproto.TestService",grpc_type="server_stream",le="0.5"} 1
+grpc_server_handling_seconds_bucket{grpc_code="OK",grpc_method="PingList",grpc_service="mwitkow.testproto.TestService",grpc_type="server_stream",le="1"} 1
+grpc_server_handling_seconds_bucket{grpc_code="OK",grpc_method="PingList",grpc_service="mwitkow.testproto.TestService",grpc_type="server_stream",le="2.5"} 1
+grpc_server_handling_seconds_bucket{grpc_code="OK",grpc_method="PingList",grpc_service="mwitkow.testproto.TestService",grpc_type="server_stream",le="5"} 1
+grpc_server_handling_seconds_bucket{grpc_code="OK",grpc_method="PingList",grpc_service="mwitkow.testproto.TestService",grpc_type="server_stream",le="10"} 1
+grpc_server_handling_seconds_bucket{grpc_code="OK",grpc_method="PingList",grpc_service="mwitkow.testproto.TestService",grpc_type="server_stream",le="+Inf"} 1
+grpc_server_handling_seconds_sum{grpc_code="OK",grpc_method="PingList",grpc_service="mwitkow.testproto.TestService",grpc_type="server_stream"} 0.0003866430000000001
+grpc_server_handling_seconds_count{grpc_code="OK",grpc_method="PingList",grpc_service="mwitkow.testproto.TestService",grpc_type="server_stream"} 1
+```
+
+
+## Useful query examples
+
+Prometheus philosophy is to provide raw metrics to the monitoring system, and
+let the aggregations be handled there. The verbosity of above metrics make it possible to have that
+flexibility. Here's a couple of useful monitoring queries:
+
+
+### request inbound rate
+```jsoniq
+sum(rate(grpc_server_started_total{job="foo"}[1m])) by (grpc_service)
+```
+For `job="foo"` (common label to differentiate between Prometheus monitoring targets), calculate the
+rate of requests per second (1 minute window) for each gRPC `grpc_service` that the job has. Please note
+how the `grpc_method` is being omitted here: all methods of a given gRPC service will be summed together.
+
+### unary request error rate
+```jsoniq
+sum(rate(grpc_server_handled_total{job="foo",grpc_type="unary",grpc_code!="OK"}[1m])) by (grpc_service)
+```
+For `job="foo"`, calculate the per-`grpc_service` rate of `unary` (1:1) RPCs that failed, i.e. the 
+ones that didn't finish with `OK` code.
+
+### unary request error percentage
+```jsoniq
+sum(rate(grpc_server_handled_total{job="foo",grpc_type="unary",grpc_code!="OK"}[1m])) by (grpc_service)
+ / 
+sum(rate(grpc_server_started_total{job="foo",grpc_type="unary"}[1m])) by (grpc_service)
+ * 100.0
+```
+For `job="foo"`, calculate the percentage of failed requests by service. It's easy to notice that
+this is a combination of the two above examples. This is an example of a query you would like to
+[alert on](https://prometheus.io/docs/alerting/rules/) in your system for SLA violations, e.g.
+"no more than 1% requests should fail".
+
+### average response stream size
+```jsoniq
+sum(rate(grpc_server_msg_sent_total{job="foo",grpc_type="server_stream"}[10m])) by (grpc_service)
+ /
+sum(rate(grpc_server_started_total{job="foo",grpc_type="server_stream"}[10m])) by (grpc_service)
+```
+For `job="foo"` what is the `grpc_service`-wide `10m` average of messages returned for all `
+server_stream` RPCs. This allows you to track the stream sizes returned by your system, e.g. allows 
+you to track when clients started to send "wide" queries that ret
+Note the divisor is the number of started RPCs, in order to account for in-flight requests.
+
+### 99%-tile latency of unary requests
+```jsoniq
+histogram_quantile(0.99, 
+  sum(rate(grpc_server_handling_seconds_bucket{job="foo",grpc_type="unary"}[5m])) by (grpc_service,le)
+)
+```
+For `job="foo"`, returns an 99%-tile [quantile estimation](https://prometheus.io/docs/practices/histograms/#quantiles)
+of the handling time of RPCs per service. Please note the `5m` rate, this means that the quantile
+estimation will take samples in a rolling `5m` window. When combined with other quantiles
+(e.g. 50%, 90%), this query gives you tremendous insight into the responsiveness of your system 
+(e.g. impact of caching).
+
+### percentage of slow unary queries (>250ms)
+```jsoniq
+100.0 - (
+sum(rate(grpc_server_handling_seconds_bucket{job="foo",grpc_type="unary",le="0.25"}[5m])) by (grpc_service)
+ / 
+sum(rate(grpc_server_handling_seconds_count{job="foo",grpc_type="unary"}[5m])) by (grpc_service)
+) * 100.0
+```
+For `job="foo"` calculate the by-`grpc_service` fraction of slow requests that took longer than `0.25` 
+seconds. This query is relatively complex, since the Prometheus aggregations use `le` (less or equal)
+buckets, meaning that counting "fast" requests fractions is easier. However, simple maths helps.
+This is an example of a query you would like to alert on in your system for SLA violations, 
+e.g. "less than 1% of requests are slower than 250ms".
+
+
+## Status
+
+This code has been used since August 2015 as the basis for monitoring of *production* gRPC micro services  at [Improbable](https://improbable.io).
+
+## License
+
+`go-grpc-prometheus` is released under the Apache 2.0 license. See the [LICENSE](LICENSE) file for details.
diff --git a/vendor/github.com/grpc-ecosystem/go-grpc-prometheus/client.go b/vendor/github.com/grpc-ecosystem/go-grpc-prometheus/client.go
new file mode 100644
index 0000000..751a4c7
--- /dev/null
+++ b/vendor/github.com/grpc-ecosystem/go-grpc-prometheus/client.go
@@ -0,0 +1,39 @@
+// Copyright 2016 Michal Witkowski. All Rights Reserved.
+// See LICENSE for licensing terms.
+
+// gRPC Prometheus monitoring interceptors for client-side gRPC.
+
+package grpc_prometheus
+
+import (
+	prom "github.com/prometheus/client_golang/prometheus"
+)
+
+var (
+	// DefaultClientMetrics is the default instance of ClientMetrics. It is
+	// intended to be used in conjunction the default Prometheus metrics
+	// registry.
+	DefaultClientMetrics = NewClientMetrics()
+
+	// UnaryClientInterceptor is a gRPC client-side interceptor that provides Prometheus monitoring for Unary RPCs.
+	UnaryClientInterceptor = DefaultClientMetrics.UnaryClientInterceptor()
+
+	// StreamClientInterceptor is a gRPC client-side interceptor that provides Prometheus monitoring for Streaming RPCs.
+	StreamClientInterceptor = DefaultClientMetrics.StreamClientInterceptor()
+)
+
+func init() {
+	prom.MustRegister(DefaultClientMetrics.clientStartedCounter)
+	prom.MustRegister(DefaultClientMetrics.clientHandledCounter)
+	prom.MustRegister(DefaultClientMetrics.clientStreamMsgReceived)
+	prom.MustRegister(DefaultClientMetrics.clientStreamMsgSent)
+}
+
+// EnableClientHandlingTimeHistogram turns on recording of handling time of
+// RPCs. Histogram metrics can be very expensive for Prometheus to retain and
+// query. This function acts on the DefaultClientMetrics variable and the
+// default Prometheus metrics registry.
+func EnableClientHandlingTimeHistogram(opts ...HistogramOption) {
+	DefaultClientMetrics.EnableClientHandlingTimeHistogram(opts...)
+	prom.Register(DefaultClientMetrics.clientHandledHistogram)
+}
diff --git a/vendor/github.com/grpc-ecosystem/go-grpc-prometheus/client_metrics.go b/vendor/github.com/grpc-ecosystem/go-grpc-prometheus/client_metrics.go
new file mode 100644
index 0000000..9b476f9
--- /dev/null
+++ b/vendor/github.com/grpc-ecosystem/go-grpc-prometheus/client_metrics.go
@@ -0,0 +1,170 @@
+package grpc_prometheus
+
+import (
+	"io"
+
+	prom "github.com/prometheus/client_golang/prometheus"
+	"golang.org/x/net/context"
+	"google.golang.org/grpc"
+	"google.golang.org/grpc/codes"
+	"google.golang.org/grpc/status"
+)
+
+// ClientMetrics represents a collection of metrics to be registered on a
+// Prometheus metrics registry for a gRPC client.
+type ClientMetrics struct {
+	clientStartedCounter          *prom.CounterVec
+	clientHandledCounter          *prom.CounterVec
+	clientStreamMsgReceived       *prom.CounterVec
+	clientStreamMsgSent           *prom.CounterVec
+	clientHandledHistogramEnabled bool
+	clientHandledHistogramOpts    prom.HistogramOpts
+	clientHandledHistogram        *prom.HistogramVec
+}
+
+// NewClientMetrics returns a ClientMetrics object. Use a new instance of
+// ClientMetrics when not using the default Prometheus metrics registry, for
+// example when wanting to control which metrics are added to a registry as
+// opposed to automatically adding metrics via init functions.
+func NewClientMetrics(counterOpts ...CounterOption) *ClientMetrics {
+	opts := counterOptions(counterOpts)
+	return &ClientMetrics{
+		clientStartedCounter: prom.NewCounterVec(
+			opts.apply(prom.CounterOpts{
+				Name: "grpc_client_started_total",
+				Help: "Total number of RPCs started on the client.",
+			}), []string{"grpc_type", "grpc_service", "grpc_method"}),
+
+		clientHandledCounter: prom.NewCounterVec(
+			opts.apply(prom.CounterOpts{
+				Name: "grpc_client_handled_total",
+				Help: "Total number of RPCs completed by the client, regardless of success or failure.",
+			}), []string{"grpc_type", "grpc_service", "grpc_method", "grpc_code"}),
+
+		clientStreamMsgReceived: prom.NewCounterVec(
+			opts.apply(prom.CounterOpts{
+				Name: "grpc_client_msg_received_total",
+				Help: "Total number of RPC stream messages received by the client.",
+			}), []string{"grpc_type", "grpc_service", "grpc_method"}),
+
+		clientStreamMsgSent: prom.NewCounterVec(
+			opts.apply(prom.CounterOpts{
+				Name: "grpc_client_msg_sent_total",
+				Help: "Total number of gRPC stream messages sent by the client.",
+			}), []string{"grpc_type", "grpc_service", "grpc_method"}),
+
+		clientHandledHistogramEnabled: false,
+		clientHandledHistogramOpts: prom.HistogramOpts{
+			Name:    "grpc_client_handling_seconds",
+			Help:    "Histogram of response latency (seconds) of the gRPC until it is finished by the application.",
+			Buckets: prom.DefBuckets,
+		},
+		clientHandledHistogram: nil,
+	}
+}
+
+// Describe sends the super-set of all possible descriptors of metrics
+// collected by this Collector to the provided channel and returns once
+// the last descriptor has been sent.
+func (m *ClientMetrics) Describe(ch chan<- *prom.Desc) {
+	m.clientStartedCounter.Describe(ch)
+	m.clientHandledCounter.Describe(ch)
+	m.clientStreamMsgReceived.Describe(ch)
+	m.clientStreamMsgSent.Describe(ch)
+	if m.clientHandledHistogramEnabled {
+		m.clientHandledHistogram.Describe(ch)
+	}
+}
+
+// Collect is called by the Prometheus registry when collecting
+// metrics. The implementation sends each collected metric via the
+// provided channel and returns once the last metric has been sent.
+func (m *ClientMetrics) Collect(ch chan<- prom.Metric) {
+	m.clientStartedCounter.Collect(ch)
+	m.clientHandledCounter.Collect(ch)
+	m.clientStreamMsgReceived.Collect(ch)
+	m.clientStreamMsgSent.Collect(ch)
+	if m.clientHandledHistogramEnabled {
+		m.clientHandledHistogram.Collect(ch)
+	}
+}
+
+// EnableClientHandlingTimeHistogram turns on recording of handling time of RPCs.
+// Histogram metrics can be very expensive for Prometheus to retain and query.
+func (m *ClientMetrics) EnableClientHandlingTimeHistogram(opts ...HistogramOption) {
+	for _, o := range opts {
+		o(&m.clientHandledHistogramOpts)
+	}
+	if !m.clientHandledHistogramEnabled {
+		m.clientHandledHistogram = prom.NewHistogramVec(
+			m.clientHandledHistogramOpts,
+			[]string{"grpc_type", "grpc_service", "grpc_method"},
+		)
+	}
+	m.clientHandledHistogramEnabled = true
+}
+
+// UnaryClientInterceptor is a gRPC client-side interceptor that provides Prometheus monitoring for Unary RPCs.
+func (m *ClientMetrics) UnaryClientInterceptor() func(ctx context.Context, method string, req, reply interface{}, cc *grpc.ClientConn, invoker grpc.UnaryInvoker, opts ...grpc.CallOption) error {
+	return func(ctx context.Context, method string, req, reply interface{}, cc *grpc.ClientConn, invoker grpc.UnaryInvoker, opts ...grpc.CallOption) error {
+		monitor := newClientReporter(m, Unary, method)
+		monitor.SentMessage()
+		err := invoker(ctx, method, req, reply, cc, opts...)
+		if err != nil {
+			monitor.ReceivedMessage()
+		}
+		st, _ := status.FromError(err)
+		monitor.Handled(st.Code())
+		return err
+	}
+}
+
+// StreamClientInterceptor is a gRPC client-side interceptor that provides Prometheus monitoring for Streaming RPCs.
+func (m *ClientMetrics) StreamClientInterceptor() func(ctx context.Context, desc *grpc.StreamDesc, cc *grpc.ClientConn, method string, streamer grpc.Streamer, opts ...grpc.CallOption) (grpc.ClientStream, error) {
+	return func(ctx context.Context, desc *grpc.StreamDesc, cc *grpc.ClientConn, method string, streamer grpc.Streamer, opts ...grpc.CallOption) (grpc.ClientStream, error) {
+		monitor := newClientReporter(m, clientStreamType(desc), method)
+		clientStream, err := streamer(ctx, desc, cc, method, opts...)
+		if err != nil {
+			st, _ := status.FromError(err)
+			monitor.Handled(st.Code())
+			return nil, err
+		}
+		return &monitoredClientStream{clientStream, monitor}, nil
+	}
+}
+
+func clientStreamType(desc *grpc.StreamDesc) grpcType {
+	if desc.ClientStreams && !desc.ServerStreams {
+		return ClientStream
+	} else if !desc.ClientStreams && desc.ServerStreams {
+		return ServerStream
+	}
+	return BidiStream
+}
+
+// monitoredClientStream wraps grpc.ClientStream allowing each Sent/Recv of message to increment counters.
+type monitoredClientStream struct {
+	grpc.ClientStream
+	monitor *clientReporter
+}
+
+func (s *monitoredClientStream) SendMsg(m interface{}) error {
+	err := s.ClientStream.SendMsg(m)
+	if err == nil {
+		s.monitor.SentMessage()
+	}
+	return err
+}
+
+func (s *monitoredClientStream) RecvMsg(m interface{}) error {
+	err := s.ClientStream.RecvMsg(m)
+	if err == nil {
+		s.monitor.ReceivedMessage()
+	} else if err == io.EOF {
+		s.monitor.Handled(codes.OK)
+	} else {
+		st, _ := status.FromError(err)
+		s.monitor.Handled(st.Code())
+	}
+	return err
+}
diff --git a/vendor/github.com/grpc-ecosystem/go-grpc-prometheus/client_reporter.go b/vendor/github.com/grpc-ecosystem/go-grpc-prometheus/client_reporter.go
new file mode 100644
index 0000000..cbf1532
--- /dev/null
+++ b/vendor/github.com/grpc-ecosystem/go-grpc-prometheus/client_reporter.go
@@ -0,0 +1,46 @@
+// Copyright 2016 Michal Witkowski. All Rights Reserved.
+// See LICENSE for licensing terms.
+
+package grpc_prometheus
+
+import (
+	"time"
+
+	"google.golang.org/grpc/codes"
+)
+
+type clientReporter struct {
+	metrics     *ClientMetrics
+	rpcType     grpcType
+	serviceName string
+	methodName  string
+	startTime   time.Time
+}
+
+func newClientReporter(m *ClientMetrics, rpcType grpcType, fullMethod string) *clientReporter {
+	r := &clientReporter{
+		metrics: m,
+		rpcType: rpcType,
+	}
+	if r.metrics.clientHandledHistogramEnabled {
+		r.startTime = time.Now()
+	}
+	r.serviceName, r.methodName = splitMethodName(fullMethod)
+	r.metrics.clientStartedCounter.WithLabelValues(string(r.rpcType), r.serviceName, r.methodName).Inc()
+	return r
+}
+
+func (r *clientReporter) ReceivedMessage() {
+	r.metrics.clientStreamMsgReceived.WithLabelValues(string(r.rpcType), r.serviceName, r.methodName).Inc()
+}
+
+func (r *clientReporter) SentMessage() {
+	r.metrics.clientStreamMsgSent.WithLabelValues(string(r.rpcType), r.serviceName, r.methodName).Inc()
+}
+
+func (r *clientReporter) Handled(code codes.Code) {
+	r.metrics.clientHandledCounter.WithLabelValues(string(r.rpcType), r.serviceName, r.methodName, code.String()).Inc()
+	if r.metrics.clientHandledHistogramEnabled {
+		r.metrics.clientHandledHistogram.WithLabelValues(string(r.rpcType), r.serviceName, r.methodName).Observe(time.Since(r.startTime).Seconds())
+	}
+}
diff --git a/vendor/github.com/grpc-ecosystem/go-grpc-prometheus/makefile b/vendor/github.com/grpc-ecosystem/go-grpc-prometheus/makefile
new file mode 100644
index 0000000..74c0842
--- /dev/null
+++ b/vendor/github.com/grpc-ecosystem/go-grpc-prometheus/makefile
@@ -0,0 +1,16 @@
+SHELL="/bin/bash"
+
+GOFILES_NOVENDOR = $(shell go list ./... | grep -v /vendor/)
+
+all: vet fmt test
+
+fmt:
+	go fmt $(GOFILES_NOVENDOR)
+
+vet:
+	go vet $(GOFILES_NOVENDOR)
+
+test: vet
+	./scripts/test_all.sh
+
+.PHONY: all vet test
diff --git a/vendor/github.com/grpc-ecosystem/go-grpc-prometheus/metric_options.go b/vendor/github.com/grpc-ecosystem/go-grpc-prometheus/metric_options.go
new file mode 100644
index 0000000..9d51aec
--- /dev/null
+++ b/vendor/github.com/grpc-ecosystem/go-grpc-prometheus/metric_options.go
@@ -0,0 +1,41 @@
+package grpc_prometheus
+
+import (
+	prom "github.com/prometheus/client_golang/prometheus"
+)
+
+// A CounterOption lets you add options to Counter metrics using With* funcs.
+type CounterOption func(*prom.CounterOpts)
+
+type counterOptions []CounterOption
+
+func (co counterOptions) apply(o prom.CounterOpts) prom.CounterOpts {
+	for _, f := range co {
+		f(&o)
+	}
+	return o
+}
+
+// WithConstLabels allows you to add ConstLabels to Counter metrics.
+func WithConstLabels(labels prom.Labels) CounterOption {
+	return func(o *prom.CounterOpts) {
+		o.ConstLabels = labels
+	}
+}
+
+// A HistogramOption lets you add options to Histogram metrics using With*
+// funcs.
+type HistogramOption func(*prom.HistogramOpts)
+
+// WithHistogramBuckets allows you to specify custom bucket ranges for histograms if EnableHandlingTimeHistogram is on.
+func WithHistogramBuckets(buckets []float64) HistogramOption {
+	return func(o *prom.HistogramOpts) { o.Buckets = buckets }
+}
+
+// WithHistogramConstLabels allows you to add custom ConstLabels to
+// histograms metrics.
+func WithHistogramConstLabels(labels prom.Labels) HistogramOption {
+	return func(o *prom.HistogramOpts) {
+		o.ConstLabels = labels
+	}
+}
diff --git a/vendor/github.com/grpc-ecosystem/go-grpc-prometheus/server.go b/vendor/github.com/grpc-ecosystem/go-grpc-prometheus/server.go
new file mode 100644
index 0000000..322f990
--- /dev/null
+++ b/vendor/github.com/grpc-ecosystem/go-grpc-prometheus/server.go
@@ -0,0 +1,48 @@
+// Copyright 2016 Michal Witkowski. All Rights Reserved.
+// See LICENSE for licensing terms.
+
+// gRPC Prometheus monitoring interceptors for server-side gRPC.
+
+package grpc_prometheus
+
+import (
+	prom "github.com/prometheus/client_golang/prometheus"
+	"google.golang.org/grpc"
+)
+
+var (
+	// DefaultServerMetrics is the default instance of ServerMetrics. It is
+	// intended to be used in conjunction the default Prometheus metrics
+	// registry.
+	DefaultServerMetrics = NewServerMetrics()
+
+	// UnaryServerInterceptor is a gRPC server-side interceptor that provides Prometheus monitoring for Unary RPCs.
+	UnaryServerInterceptor = DefaultServerMetrics.UnaryServerInterceptor()
+
+	// StreamServerInterceptor is a gRPC server-side interceptor that provides Prometheus monitoring for Streaming RPCs.
+	StreamServerInterceptor = DefaultServerMetrics.StreamServerInterceptor()
+)
+
+func init() {
+	prom.MustRegister(DefaultServerMetrics.serverStartedCounter)
+	prom.MustRegister(DefaultServerMetrics.serverHandledCounter)
+	prom.MustRegister(DefaultServerMetrics.serverStreamMsgReceived)
+	prom.MustRegister(DefaultServerMetrics.serverStreamMsgSent)
+}
+
+// Register takes a gRPC server and pre-initializes all counters to 0. This
+// allows for easier monitoring in Prometheus (no missing metrics), and should
+// be called *after* all services have been registered with the server. This
+// function acts on the DefaultServerMetrics variable.
+func Register(server *grpc.Server) {
+	DefaultServerMetrics.InitializeMetrics(server)
+}
+
+// EnableHandlingTimeHistogram turns on recording of handling time
+// of RPCs. Histogram metrics can be very expensive for Prometheus
+// to retain and query. This function acts on the DefaultServerMetrics
+// variable and the default Prometheus metrics registry.
+func EnableHandlingTimeHistogram(opts ...HistogramOption) {
+	DefaultServerMetrics.EnableHandlingTimeHistogram(opts...)
+	prom.Register(DefaultServerMetrics.serverHandledHistogram)
+}
diff --git a/vendor/github.com/grpc-ecosystem/go-grpc-prometheus/server_metrics.go b/vendor/github.com/grpc-ecosystem/go-grpc-prometheus/server_metrics.go
new file mode 100644
index 0000000..5b1467e
--- /dev/null
+++ b/vendor/github.com/grpc-ecosystem/go-grpc-prometheus/server_metrics.go
@@ -0,0 +1,185 @@
+package grpc_prometheus
+
+import (
+	prom "github.com/prometheus/client_golang/prometheus"
+	"golang.org/x/net/context"
+	"google.golang.org/grpc"
+	"google.golang.org/grpc/status"
+)
+
+// ServerMetrics represents a collection of metrics to be registered on a
+// Prometheus metrics registry for a gRPC server.
+type ServerMetrics struct {
+	serverStartedCounter          *prom.CounterVec
+	serverHandledCounter          *prom.CounterVec
+	serverStreamMsgReceived       *prom.CounterVec
+	serverStreamMsgSent           *prom.CounterVec
+	serverHandledHistogramEnabled bool
+	serverHandledHistogramOpts    prom.HistogramOpts
+	serverHandledHistogram        *prom.HistogramVec
+}
+
+// NewServerMetrics returns a ServerMetrics object. Use a new instance of
+// ServerMetrics when not using the default Prometheus metrics registry, for
+// example when wanting to control which metrics are added to a registry as
+// opposed to automatically adding metrics via init functions.
+func NewServerMetrics(counterOpts ...CounterOption) *ServerMetrics {
+	opts := counterOptions(counterOpts)
+	return &ServerMetrics{
+		serverStartedCounter: prom.NewCounterVec(
+			opts.apply(prom.CounterOpts{
+				Name: "grpc_server_started_total",
+				Help: "Total number of RPCs started on the server.",
+			}), []string{"grpc_type", "grpc_service", "grpc_method"}),
+		serverHandledCounter: prom.NewCounterVec(
+			opts.apply(prom.CounterOpts{
+				Name: "grpc_server_handled_total",
+				Help: "Total number of RPCs completed on the server, regardless of success or failure.",
+			}), []string{"grpc_type", "grpc_service", "grpc_method", "grpc_code"}),
+		serverStreamMsgReceived: prom.NewCounterVec(
+			opts.apply(prom.CounterOpts{
+				Name: "grpc_server_msg_received_total",
+				Help: "Total number of RPC stream messages received on the server.",
+			}), []string{"grpc_type", "grpc_service", "grpc_method"}),
+		serverStreamMsgSent: prom.NewCounterVec(
+			opts.apply(prom.CounterOpts{
+				Name: "grpc_server_msg_sent_total",
+				Help: "Total number of gRPC stream messages sent by the server.",
+			}), []string{"grpc_type", "grpc_service", "grpc_method"}),
+		serverHandledHistogramEnabled: false,
+		serverHandledHistogramOpts: prom.HistogramOpts{
+			Name:    "grpc_server_handling_seconds",
+			Help:    "Histogram of response latency (seconds) of gRPC that had been application-level handled by the server.",
+			Buckets: prom.DefBuckets,
+		},
+		serverHandledHistogram: nil,
+	}
+}
+
+// EnableHandlingTimeHistogram enables histograms being registered when
+// registering the ServerMetrics on a Prometheus registry. Histograms can be
+// expensive on Prometheus servers. It takes options to configure histogram
+// options such as the defined buckets.
+func (m *ServerMetrics) EnableHandlingTimeHistogram(opts ...HistogramOption) {
+	for _, o := range opts {
+		o(&m.serverHandledHistogramOpts)
+	}
+	if !m.serverHandledHistogramEnabled {
+		m.serverHandledHistogram = prom.NewHistogramVec(
+			m.serverHandledHistogramOpts,
+			[]string{"grpc_type", "grpc_service", "grpc_method"},
+		)
+	}
+	m.serverHandledHistogramEnabled = true
+}
+
+// Describe sends the super-set of all possible descriptors of metrics
+// collected by this Collector to the provided channel and returns once
+// the last descriptor has been sent.
+func (m *ServerMetrics) Describe(ch chan<- *prom.Desc) {
+	m.serverStartedCounter.Describe(ch)
+	m.serverHandledCounter.Describe(ch)
+	m.serverStreamMsgReceived.Describe(ch)
+	m.serverStreamMsgSent.Describe(ch)
+	if m.serverHandledHistogramEnabled {
+		m.serverHandledHistogram.Describe(ch)
+	}
+}
+
+// Collect is called by the Prometheus registry when collecting
+// metrics. The implementation sends each collected metric via the
+// provided channel and returns once the last metric has been sent.
+func (m *ServerMetrics) Collect(ch chan<- prom.Metric) {
+	m.serverStartedCounter.Collect(ch)
+	m.serverHandledCounter.Collect(ch)
+	m.serverStreamMsgReceived.Collect(ch)
+	m.serverStreamMsgSent.Collect(ch)
+	if m.serverHandledHistogramEnabled {
+		m.serverHandledHistogram.Collect(ch)
+	}
+}
+
+// UnaryServerInterceptor is a gRPC server-side interceptor that provides Prometheus monitoring for Unary RPCs.
+func (m *ServerMetrics) UnaryServerInterceptor() func(ctx context.Context, req interface{}, info *grpc.UnaryServerInfo, handler grpc.UnaryHandler) (interface{}, error) {
+	return func(ctx context.Context, req interface{}, info *grpc.UnaryServerInfo, handler grpc.UnaryHandler) (interface{}, error) {
+		monitor := newServerReporter(m, Unary, info.FullMethod)
+		monitor.ReceivedMessage()
+		resp, err := handler(ctx, req)
+		st, _ := status.FromError(err)
+		monitor.Handled(st.Code())
+		if err == nil {
+			monitor.SentMessage()
+		}
+		return resp, err
+	}
+}
+
+// StreamServerInterceptor is a gRPC server-side interceptor that provides Prometheus monitoring for Streaming RPCs.
+func (m *ServerMetrics) StreamServerInterceptor() func(srv interface{}, ss grpc.ServerStream, info *grpc.StreamServerInfo, handler grpc.StreamHandler) error {
+	return func(srv interface{}, ss grpc.ServerStream, info *grpc.StreamServerInfo, handler grpc.StreamHandler) error {
+		monitor := newServerReporter(m, streamRPCType(info), info.FullMethod)
+		err := handler(srv, &monitoredServerStream{ss, monitor})
+		st, _ := status.FromError(err)
+		monitor.Handled(st.Code())
+		return err
+	}
+}
+
+// InitializeMetrics initializes all metrics, with their appropriate null
+// value, for all gRPC methods registered on a gRPC server. This is useful, to
+// ensure that all metrics exist when collecting and querying.
+func (m *ServerMetrics) InitializeMetrics(server *grpc.Server) {
+	serviceInfo := server.GetServiceInfo()
+	for serviceName, info := range serviceInfo {
+		for _, mInfo := range info.Methods {
+			preRegisterMethod(m, serviceName, &mInfo)
+		}
+	}
+}
+
+func streamRPCType(info *grpc.StreamServerInfo) grpcType {
+	if info.IsClientStream && !info.IsServerStream {
+		return ClientStream
+	} else if !info.IsClientStream && info.IsServerStream {
+		return ServerStream
+	}
+	return BidiStream
+}
+
+// monitoredStream wraps grpc.ServerStream allowing each Sent/Recv of message to increment counters.
+type monitoredServerStream struct {
+	grpc.ServerStream
+	monitor *serverReporter
+}
+
+func (s *monitoredServerStream) SendMsg(m interface{}) error {
+	err := s.ServerStream.SendMsg(m)
+	if err == nil {
+		s.monitor.SentMessage()
+	}
+	return err
+}
+
+func (s *monitoredServerStream) RecvMsg(m interface{}) error {
+	err := s.ServerStream.RecvMsg(m)
+	if err == nil {
+		s.monitor.ReceivedMessage()
+	}
+	return err
+}
+
+// preRegisterMethod is invoked on Register of a Server, allowing all gRPC services labels to be pre-populated.
+func preRegisterMethod(metrics *ServerMetrics, serviceName string, mInfo *grpc.MethodInfo) {
+	methodName := mInfo.Name
+	methodType := string(typeFromMethodInfo(mInfo))
+	// These are just references (no increments), as just referencing will create the labels but not set values.
+	metrics.serverStartedCounter.GetMetricWithLabelValues(methodType, serviceName, methodName)
+	metrics.serverStreamMsgReceived.GetMetricWithLabelValues(methodType, serviceName, methodName)
+	metrics.serverStreamMsgSent.GetMetricWithLabelValues(methodType, serviceName, methodName)
+	if metrics.serverHandledHistogramEnabled {
+		metrics.serverHandledHistogram.GetMetricWithLabelValues(methodType, serviceName, methodName)
+	}
+	for _, code := range allCodes {
+		metrics.serverHandledCounter.GetMetricWithLabelValues(methodType, serviceName, methodName, code.String())
+	}
+}
diff --git a/vendor/github.com/grpc-ecosystem/go-grpc-prometheus/server_reporter.go b/vendor/github.com/grpc-ecosystem/go-grpc-prometheus/server_reporter.go
new file mode 100644
index 0000000..aa9db54
--- /dev/null
+++ b/vendor/github.com/grpc-ecosystem/go-grpc-prometheus/server_reporter.go
@@ -0,0 +1,46 @@
+// Copyright 2016 Michal Witkowski. All Rights Reserved.
+// See LICENSE for licensing terms.
+
+package grpc_prometheus
+
+import (
+	"time"
+
+	"google.golang.org/grpc/codes"
+)
+
+type serverReporter struct {
+	metrics     *ServerMetrics
+	rpcType     grpcType
+	serviceName string
+	methodName  string
+	startTime   time.Time
+}
+
+func newServerReporter(m *ServerMetrics, rpcType grpcType, fullMethod string) *serverReporter {
+	r := &serverReporter{
+		metrics: m,
+		rpcType: rpcType,
+	}
+	if r.metrics.serverHandledHistogramEnabled {
+		r.startTime = time.Now()
+	}
+	r.serviceName, r.methodName = splitMethodName(fullMethod)
+	r.metrics.serverStartedCounter.WithLabelValues(string(r.rpcType), r.serviceName, r.methodName).Inc()
+	return r
+}
+
+func (r *serverReporter) ReceivedMessage() {
+	r.metrics.serverStreamMsgReceived.WithLabelValues(string(r.rpcType), r.serviceName, r.methodName).Inc()
+}
+
+func (r *serverReporter) SentMessage() {
+	r.metrics.serverStreamMsgSent.WithLabelValues(string(r.rpcType), r.serviceName, r.methodName).Inc()
+}
+
+func (r *serverReporter) Handled(code codes.Code) {
+	r.metrics.serverHandledCounter.WithLabelValues(string(r.rpcType), r.serviceName, r.methodName, code.String()).Inc()
+	if r.metrics.serverHandledHistogramEnabled {
+		r.metrics.serverHandledHistogram.WithLabelValues(string(r.rpcType), r.serviceName, r.methodName).Observe(time.Since(r.startTime).Seconds())
+	}
+}
diff --git a/vendor/github.com/grpc-ecosystem/go-grpc-prometheus/util.go b/vendor/github.com/grpc-ecosystem/go-grpc-prometheus/util.go
new file mode 100644
index 0000000..7987de3
--- /dev/null
+++ b/vendor/github.com/grpc-ecosystem/go-grpc-prometheus/util.go
@@ -0,0 +1,50 @@
+// Copyright 2016 Michal Witkowski. All Rights Reserved.
+// See LICENSE for licensing terms.
+
+package grpc_prometheus
+
+import (
+	"strings"
+
+	"google.golang.org/grpc"
+	"google.golang.org/grpc/codes"
+)
+
+type grpcType string
+
+const (
+	Unary        grpcType = "unary"
+	ClientStream grpcType = "client_stream"
+	ServerStream grpcType = "server_stream"
+	BidiStream   grpcType = "bidi_stream"
+)
+
+var (
+	allCodes = []codes.Code{
+		codes.OK, codes.Canceled, codes.Unknown, codes.InvalidArgument, codes.DeadlineExceeded, codes.NotFound,
+		codes.AlreadyExists, codes.PermissionDenied, codes.Unauthenticated, codes.ResourceExhausted,
+		codes.FailedPrecondition, codes.Aborted, codes.OutOfRange, codes.Unimplemented, codes.Internal,
+		codes.Unavailable, codes.DataLoss,
+	}
+)
+
+func splitMethodName(fullMethodName string) (string, string) {
+	fullMethodName = strings.TrimPrefix(fullMethodName, "/") // remove leading slash
+	if i := strings.Index(fullMethodName, "/"); i >= 0 {
+		return fullMethodName[:i], fullMethodName[i+1:]
+	}
+	return "unknown", "unknown"
+}
+
+func typeFromMethodInfo(mInfo *grpc.MethodInfo) grpcType {
+	if !mInfo.IsClientStream && !mInfo.IsServerStream {
+		return Unary
+	}
+	if mInfo.IsClientStream && !mInfo.IsServerStream {
+		return ClientStream
+	}
+	if !mInfo.IsClientStream && mInfo.IsServerStream {
+		return ServerStream
+	}
+	return BidiStream
+}