[VOL-4638] Initial commit
Change-Id: I5e785d017e1d27783b24591b52f20f442895e602
diff --git a/vendor/github.com/opentracing/opentracing-go/.gitignore b/vendor/github.com/opentracing/opentracing-go/.gitignore
new file mode 100644
index 0000000..c57100a
--- /dev/null
+++ b/vendor/github.com/opentracing/opentracing-go/.gitignore
@@ -0,0 +1 @@
+coverage.txt
diff --git a/vendor/github.com/opentracing/opentracing-go/.travis.yml b/vendor/github.com/opentracing/opentracing-go/.travis.yml
new file mode 100644
index 0000000..b950e42
--- /dev/null
+++ b/vendor/github.com/opentracing/opentracing-go/.travis.yml
@@ -0,0 +1,20 @@
+language: go
+
+matrix:
+ include:
+ - go: "1.13.x"
+ - go: "1.14.x"
+ - go: "tip"
+ env:
+ - LINT=true
+ - COVERAGE=true
+
+install:
+ - if [ "$LINT" == true ]; then go get -u golang.org/x/lint/golint/... ; else echo 'skipping lint'; fi
+ - go get -u github.com/stretchr/testify/...
+
+script:
+ - make test
+ - go build ./...
+ - if [ "$LINT" == true ]; then make lint ; else echo 'skipping lint'; fi
+ - if [ "$COVERAGE" == true ]; then make cover && bash <(curl -s https://codecov.io/bash) ; else echo 'skipping coverage'; fi
diff --git a/vendor/github.com/opentracing/opentracing-go/CHANGELOG.md b/vendor/github.com/opentracing/opentracing-go/CHANGELOG.md
new file mode 100644
index 0000000..d3bfcf6
--- /dev/null
+++ b/vendor/github.com/opentracing/opentracing-go/CHANGELOG.md
@@ -0,0 +1,63 @@
+Changes by Version
+==================
+
+
+1.2.0 (2020-07-01)
+-------------------
+
+* Restore the ability to reset the current span in context to nil (#231) -- Yuri Shkuro
+* Use error.object per OpenTracing Semantic Conventions (#179) -- Rahman Syed
+* Convert nil pointer log field value to string "nil" (#230) -- Cyril Tovena
+* Add Go module support (#215) -- Zaba505
+* Make SetTag helper types in ext public (#229) -- Blake Edwards
+* Add log/fields helpers for keys from specification (#226) -- Dmitry Monakhov
+* Improve noop impementation (#223) -- chanxuehong
+* Add an extension to Tracer interface for custom go context creation (#220) -- Krzesimir Nowak
+* Fix typo in comments (#222) -- meteorlxy
+* Improve documentation for log.Object() to emphasize the requirement to pass immutable arguments (#219) -- 疯狂的小企鹅
+* [mock] Return ErrInvalidSpanContext if span context is not MockSpanContext (#216) -- Milad Irannejad
+
+
+1.1.0 (2019-03-23)
+-------------------
+
+Notable changes:
+- The library is now released under Apache 2.0 license
+- Use Set() instead of Add() in HTTPHeadersCarrier is functionally a breaking change (fixes issue [#159](https://github.com/opentracing/opentracing-go/issues/159))
+- 'golang.org/x/net/context' is replaced with 'context' from the standard library
+
+List of all changes:
+
+- Export StartSpanFromContextWithTracer (#214) <Aaron Delaney>
+- Add IsGlobalTracerRegistered() to indicate if a tracer has been registered (#201) <Mike Goldsmith>
+- Use Set() instead of Add() in HTTPHeadersCarrier (#191) <jeremyxu2010>
+- Update license to Apache 2.0 (#181) <Andrea Kao>
+- Replace 'golang.org/x/net/context' with 'context' (#176) <Tony Ghita>
+- Port of Python opentracing/harness/api_check.py to Go (#146) <chris erway>
+- Fix race condition in MockSpan.Context() (#170) <Brad>
+- Add PeerHostIPv4.SetString() (#155) <NeoCN>
+- Add a Noop log field type to log to allow for optional fields (#150) <Matt Ho>
+
+
+1.0.2 (2017-04-26)
+-------------------
+
+- Add more semantic tags (#139) <Rustam Zagirov>
+
+
+1.0.1 (2017-02-06)
+-------------------
+
+- Correct spelling in comments <Ben Sigelman>
+- Address race in nextMockID() (#123) <bill fumerola>
+- log: avoid panic marshaling nil error (#131) <Anthony Voutas>
+- Deprecate InitGlobalTracer in favor of SetGlobalTracer (#128) <Yuri Shkuro>
+- Drop Go 1.5 that fails in Travis (#129) <Yuri Shkuro>
+- Add convenience methods Key() and Value() to log.Field <Ben Sigelman>
+- Add convenience methods to log.Field (2 years, 6 months ago) <Radu Berinde>
+
+1.0.0 (2016-09-26)
+-------------------
+
+- This release implements OpenTracing Specification 1.0 (https://opentracing.io/spec)
+
diff --git a/vendor/github.com/opentracing/opentracing-go/LICENSE b/vendor/github.com/opentracing/opentracing-go/LICENSE
new file mode 100644
index 0000000..f002734
--- /dev/null
+++ b/vendor/github.com/opentracing/opentracing-go/LICENSE
@@ -0,0 +1,201 @@
+ Apache License
+ Version 2.0, January 2004
+ http://www.apache.org/licenses/
+
+ TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+ 1. Definitions.
+
+ "License" shall mean the terms and conditions for use, reproduction,
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+ You may add Your own copyright statement to Your modifications and
+ may provide additional or different license terms and conditions
+ for use, reproduction, or distribution of Your modifications, or
+ for any such Derivative Works as a whole, provided Your use,
+ reproduction, and distribution of the Work otherwise complies with
+ the conditions stated in this License.
+
+ 5. Submission of Contributions. Unless You explicitly state otherwise,
+ any Contribution intentionally submitted for inclusion in the Work
+ by You to the Licensor shall be under the terms and conditions of
+ this License, without any additional terms or conditions.
+ Notwithstanding the above, nothing herein shall supersede or modify
+ the terms of any separate license agreement you may have executed
+ with Licensor regarding such Contributions.
+
+ 6. Trademarks. This License does not grant permission to use the trade
+ names, trademarks, service marks, or product names of the Licensor,
+ except as required for reasonable and customary use in describing the
+ origin of the Work and reproducing the content of the NOTICE file.
+
+ 7. Disclaimer of Warranty. Unless required by applicable law or
+ agreed to in writing, Licensor provides the Work (and each
+ Contributor provides its Contributions) on an "AS IS" BASIS,
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+ appropriateness of using or redistributing the Work and assume any
+ risks associated with Your exercise of permissions under this License.
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+ 8. Limitation of Liability. In no event and under no legal theory,
+ whether in tort (including negligence), contract, or otherwise,
+ unless required by applicable law (such as deliberate and grossly
+ negligent acts) or agreed to in writing, shall any Contributor be
+ liable to You for damages, including any direct, indirect, special,
+ incidental, or consequential damages of any character arising as a
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+ Work (including but not limited to damages for loss of goodwill,
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+ other commercial damages or losses), even if such Contributor
+ has been advised of the possibility of such damages.
+
+ 9. Accepting Warranty or Additional Liability. While redistributing
+ the Work or Derivative Works thereof, You may choose to offer,
+ and charge a fee for, acceptance of support, warranty, indemnity,
+ or other liability obligations and/or rights consistent with this
+ License. However, in accepting such obligations, You may act only
+ on Your own behalf and on Your sole responsibility, not on behalf
+ of any other Contributor, and only if You agree to indemnify,
+ defend, and hold each Contributor harmless for any liability
+ incurred by, or claims asserted against, such Contributor by reason
+ of your accepting any such warranty or additional liability.
+
+ END OF TERMS AND CONDITIONS
+
+ APPENDIX: How to apply the Apache License to your work.
+
+ To apply the Apache License to your work, attach the following
+ boilerplate notice, with the fields enclosed by brackets "{}"
+ replaced with your own identifying information. (Don't include
+ the brackets!) The text should be enclosed in the appropriate
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+ Copyright 2016 The OpenTracing Authors
+
+ Licensed under the Apache License, Version 2.0 (the "License");
+ you may not use this file except in compliance with the License.
+ You may obtain a copy of the License at
+
+ http://www.apache.org/licenses/LICENSE-2.0
+
+ Unless required by applicable law or agreed to in writing, software
+ distributed under the License is distributed on an "AS IS" BASIS,
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+ See the License for the specific language governing permissions and
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diff --git a/vendor/github.com/opentracing/opentracing-go/Makefile b/vendor/github.com/opentracing/opentracing-go/Makefile
new file mode 100644
index 0000000..62abb63
--- /dev/null
+++ b/vendor/github.com/opentracing/opentracing-go/Makefile
@@ -0,0 +1,20 @@
+.DEFAULT_GOAL := test-and-lint
+
+.PHONY: test-and-lint
+test-and-lint: test lint
+
+.PHONY: test
+test:
+ go test -v -cover -race ./...
+
+.PHONY: cover
+cover:
+ go test -v -coverprofile=coverage.txt -covermode=atomic -race ./...
+
+.PHONY: lint
+lint:
+ go fmt ./...
+ golint ./...
+ @# Run again with magic to exit non-zero if golint outputs anything.
+ @! (golint ./... | read dummy)
+ go vet ./...
diff --git a/vendor/github.com/opentracing/opentracing-go/README.md b/vendor/github.com/opentracing/opentracing-go/README.md
new file mode 100644
index 0000000..6ef1d7c
--- /dev/null
+++ b/vendor/github.com/opentracing/opentracing-go/README.md
@@ -0,0 +1,171 @@
+[](https://gitter.im/opentracing/public) [](https://travis-ci.org/opentracing/opentracing-go) [](http://godoc.org/github.com/opentracing/opentracing-go)
+[](https://sourcegraph.com/github.com/opentracing/opentracing-go?badge)
+
+# OpenTracing API for Go
+
+This package is a Go platform API for OpenTracing.
+
+## Required Reading
+
+In order to understand the Go platform API, one must first be familiar with the
+[OpenTracing project](https://opentracing.io) and
+[terminology](https://opentracing.io/specification/) more specifically.
+
+## API overview for those adding instrumentation
+
+Everyday consumers of this `opentracing` package really only need to worry
+about a couple of key abstractions: the `StartSpan` function, the `Span`
+interface, and binding a `Tracer` at `main()`-time. Here are code snippets
+demonstrating some important use cases.
+
+#### Singleton initialization
+
+The simplest starting point is `./default_tracer.go`. As early as possible, call
+
+```go
+ import "github.com/opentracing/opentracing-go"
+ import ".../some_tracing_impl"
+
+ func main() {
+ opentracing.SetGlobalTracer(
+ // tracing impl specific:
+ some_tracing_impl.New(...),
+ )
+ ...
+ }
+```
+
+#### Non-Singleton initialization
+
+If you prefer direct control to singletons, manage ownership of the
+`opentracing.Tracer` implementation explicitly.
+
+#### Creating a Span given an existing Go `context.Context`
+
+If you use `context.Context` in your application, OpenTracing's Go library will
+happily rely on it for `Span` propagation. To start a new (blocking child)
+`Span`, you can use `StartSpanFromContext`.
+
+```go
+ func xyz(ctx context.Context, ...) {
+ ...
+ span, ctx := opentracing.StartSpanFromContext(ctx, "operation_name")
+ defer span.Finish()
+ span.LogFields(
+ log.String("event", "soft error"),
+ log.String("type", "cache timeout"),
+ log.Int("waited.millis", 1500))
+ ...
+ }
+```
+
+#### Starting an empty trace by creating a "root span"
+
+It's always possible to create a "root" `Span` with no parent or other causal
+reference.
+
+```go
+ func xyz() {
+ ...
+ sp := opentracing.StartSpan("operation_name")
+ defer sp.Finish()
+ ...
+ }
+```
+
+#### Creating a (child) Span given an existing (parent) Span
+
+```go
+ func xyz(parentSpan opentracing.Span, ...) {
+ ...
+ sp := opentracing.StartSpan(
+ "operation_name",
+ opentracing.ChildOf(parentSpan.Context()))
+ defer sp.Finish()
+ ...
+ }
+```
+
+#### Serializing to the wire
+
+```go
+ func makeSomeRequest(ctx context.Context) ... {
+ if span := opentracing.SpanFromContext(ctx); span != nil {
+ httpClient := &http.Client{}
+ httpReq, _ := http.NewRequest("GET", "http://myservice/", nil)
+
+ // Transmit the span's TraceContext as HTTP headers on our
+ // outbound request.
+ opentracing.GlobalTracer().Inject(
+ span.Context(),
+ opentracing.HTTPHeaders,
+ opentracing.HTTPHeadersCarrier(httpReq.Header))
+
+ resp, err := httpClient.Do(httpReq)
+ ...
+ }
+ ...
+ }
+```
+
+#### Deserializing from the wire
+
+```go
+ http.HandleFunc("/", func(w http.ResponseWriter, req *http.Request) {
+ var serverSpan opentracing.Span
+ appSpecificOperationName := ...
+ wireContext, err := opentracing.GlobalTracer().Extract(
+ opentracing.HTTPHeaders,
+ opentracing.HTTPHeadersCarrier(req.Header))
+ if err != nil {
+ // Optionally record something about err here
+ }
+
+ // Create the span referring to the RPC client if available.
+ // If wireContext == nil, a root span will be created.
+ serverSpan = opentracing.StartSpan(
+ appSpecificOperationName,
+ ext.RPCServerOption(wireContext))
+
+ defer serverSpan.Finish()
+
+ ctx := opentracing.ContextWithSpan(context.Background(), serverSpan)
+ ...
+ }
+```
+
+#### Conditionally capture a field using `log.Noop`
+
+In some situations, you may want to dynamically decide whether or not
+to log a field. For example, you may want to capture additional data,
+such as a customer ID, in non-production environments:
+
+```go
+ func Customer(order *Order) log.Field {
+ if os.Getenv("ENVIRONMENT") == "dev" {
+ return log.String("customer", order.Customer.ID)
+ }
+ return log.Noop()
+ }
+```
+
+#### Goroutine-safety
+
+The entire public API is goroutine-safe and does not require external
+synchronization.
+
+## API pointers for those implementing a tracing system
+
+Tracing system implementors may be able to reuse or copy-paste-modify the `basictracer` package, found [here](https://github.com/opentracing/basictracer-go). In particular, see `basictracer.New(...)`.
+
+## API compatibility
+
+For the time being, "mild" backwards-incompatible changes may be made without changing the major version number. As OpenTracing and `opentracing-go` mature, backwards compatibility will become more of a priority.
+
+## Tracer test suite
+
+A test suite is available in the [harness](https://godoc.org/github.com/opentracing/opentracing-go/harness) package that can assist Tracer implementors to assert that their Tracer is working correctly.
+
+## Licensing
+
+[Apache 2.0 License](./LICENSE).
diff --git a/vendor/github.com/opentracing/opentracing-go/ext.go b/vendor/github.com/opentracing/opentracing-go/ext.go
new file mode 100644
index 0000000..e11977e
--- /dev/null
+++ b/vendor/github.com/opentracing/opentracing-go/ext.go
@@ -0,0 +1,24 @@
+package opentracing
+
+import (
+ "context"
+)
+
+// TracerContextWithSpanExtension is an extension interface that the
+// implementation of the Tracer interface may want to implement. It
+// allows to have some control over the go context when the
+// ContextWithSpan is invoked.
+//
+// The primary purpose of this extension are adapters from opentracing
+// API to some other tracing API.
+type TracerContextWithSpanExtension interface {
+ // ContextWithSpanHook gets called by the ContextWithSpan
+ // function, when the Tracer implementation also implements
+ // this interface. It allows to put extra information into the
+ // context and make it available to the callers of the
+ // ContextWithSpan.
+ //
+ // This hook is invoked before the ContextWithSpan function
+ // actually puts the span into the context.
+ ContextWithSpanHook(ctx context.Context, span Span) context.Context
+}
diff --git a/vendor/github.com/opentracing/opentracing-go/ext/field.go b/vendor/github.com/opentracing/opentracing-go/ext/field.go
new file mode 100644
index 0000000..8282bd7
--- /dev/null
+++ b/vendor/github.com/opentracing/opentracing-go/ext/field.go
@@ -0,0 +1,17 @@
+package ext
+
+import (
+ "github.com/opentracing/opentracing-go"
+ "github.com/opentracing/opentracing-go/log"
+)
+
+// LogError sets the error=true tag on the Span and logs err as an "error" event.
+func LogError(span opentracing.Span, err error, fields ...log.Field) {
+ Error.Set(span, true)
+ ef := []log.Field{
+ log.Event("error"),
+ log.Error(err),
+ }
+ ef = append(ef, fields...)
+ span.LogFields(ef...)
+}
diff --git a/vendor/github.com/opentracing/opentracing-go/ext/tags.go b/vendor/github.com/opentracing/opentracing-go/ext/tags.go
new file mode 100644
index 0000000..a414b59
--- /dev/null
+++ b/vendor/github.com/opentracing/opentracing-go/ext/tags.go
@@ -0,0 +1,215 @@
+package ext
+
+import "github.com/opentracing/opentracing-go"
+
+// These constants define common tag names recommended for better portability across
+// tracing systems and languages/platforms.
+//
+// The tag names are defined as typed strings, so that in addition to the usual use
+//
+// span.setTag(TagName, value)
+//
+// they also support value type validation via this additional syntax:
+//
+// TagName.Set(span, value)
+//
+var (
+ //////////////////////////////////////////////////////////////////////
+ // SpanKind (client/server or producer/consumer)
+ //////////////////////////////////////////////////////////////////////
+
+ // SpanKind hints at relationship between spans, e.g. client/server
+ SpanKind = spanKindTagName("span.kind")
+
+ // SpanKindRPCClient marks a span representing the client-side of an RPC
+ // or other remote call
+ SpanKindRPCClientEnum = SpanKindEnum("client")
+ SpanKindRPCClient = opentracing.Tag{Key: string(SpanKind), Value: SpanKindRPCClientEnum}
+
+ // SpanKindRPCServer marks a span representing the server-side of an RPC
+ // or other remote call
+ SpanKindRPCServerEnum = SpanKindEnum("server")
+ SpanKindRPCServer = opentracing.Tag{Key: string(SpanKind), Value: SpanKindRPCServerEnum}
+
+ // SpanKindProducer marks a span representing the producer-side of a
+ // message bus
+ SpanKindProducerEnum = SpanKindEnum("producer")
+ SpanKindProducer = opentracing.Tag{Key: string(SpanKind), Value: SpanKindProducerEnum}
+
+ // SpanKindConsumer marks a span representing the consumer-side of a
+ // message bus
+ SpanKindConsumerEnum = SpanKindEnum("consumer")
+ SpanKindConsumer = opentracing.Tag{Key: string(SpanKind), Value: SpanKindConsumerEnum}
+
+ //////////////////////////////////////////////////////////////////////
+ // Component name
+ //////////////////////////////////////////////////////////////////////
+
+ // Component is a low-cardinality identifier of the module, library,
+ // or package that is generating a span.
+ Component = StringTagName("component")
+
+ //////////////////////////////////////////////////////////////////////
+ // Sampling hint
+ //////////////////////////////////////////////////////////////////////
+
+ // SamplingPriority determines the priority of sampling this Span.
+ SamplingPriority = Uint16TagName("sampling.priority")
+
+ //////////////////////////////////////////////////////////////////////
+ // Peer tags. These tags can be emitted by either client-side or
+ // server-side to describe the other side/service in a peer-to-peer
+ // communications, like an RPC call.
+ //////////////////////////////////////////////////////////////////////
+
+ // PeerService records the service name of the peer.
+ PeerService = StringTagName("peer.service")
+
+ // PeerAddress records the address name of the peer. This may be a "ip:port",
+ // a bare "hostname", a FQDN or even a database DSN substring
+ // like "mysql://username@127.0.0.1:3306/dbname"
+ PeerAddress = StringTagName("peer.address")
+
+ // PeerHostname records the host name of the peer
+ PeerHostname = StringTagName("peer.hostname")
+
+ // PeerHostIPv4 records IP v4 host address of the peer
+ PeerHostIPv4 = IPv4TagName("peer.ipv4")
+
+ // PeerHostIPv6 records IP v6 host address of the peer
+ PeerHostIPv6 = StringTagName("peer.ipv6")
+
+ // PeerPort records port number of the peer
+ PeerPort = Uint16TagName("peer.port")
+
+ //////////////////////////////////////////////////////////////////////
+ // HTTP Tags
+ //////////////////////////////////////////////////////////////////////
+
+ // HTTPUrl should be the URL of the request being handled in this segment
+ // of the trace, in standard URI format. The protocol is optional.
+ HTTPUrl = StringTagName("http.url")
+
+ // HTTPMethod is the HTTP method of the request, and is case-insensitive.
+ HTTPMethod = StringTagName("http.method")
+
+ // HTTPStatusCode is the numeric HTTP status code (200, 404, etc) of the
+ // HTTP response.
+ HTTPStatusCode = Uint16TagName("http.status_code")
+
+ //////////////////////////////////////////////////////////////////////
+ // DB Tags
+ //////////////////////////////////////////////////////////////////////
+
+ // DBInstance is database instance name.
+ DBInstance = StringTagName("db.instance")
+
+ // DBStatement is a database statement for the given database type.
+ // It can be a query or a prepared statement (i.e., before substitution).
+ DBStatement = StringTagName("db.statement")
+
+ // DBType is a database type. For any SQL database, "sql".
+ // For others, the lower-case database category, e.g. "redis"
+ DBType = StringTagName("db.type")
+
+ // DBUser is a username for accessing database.
+ DBUser = StringTagName("db.user")
+
+ //////////////////////////////////////////////////////////////////////
+ // Message Bus Tag
+ //////////////////////////////////////////////////////////////////////
+
+ // MessageBusDestination is an address at which messages can be exchanged
+ MessageBusDestination = StringTagName("message_bus.destination")
+
+ //////////////////////////////////////////////////////////////////////
+ // Error Tag
+ //////////////////////////////////////////////////////////////////////
+
+ // Error indicates that operation represented by the span resulted in an error.
+ Error = BoolTagName("error")
+)
+
+// ---
+
+// SpanKindEnum represents common span types
+type SpanKindEnum string
+
+type spanKindTagName string
+
+// Set adds a string tag to the `span`
+func (tag spanKindTagName) Set(span opentracing.Span, value SpanKindEnum) {
+ span.SetTag(string(tag), value)
+}
+
+type rpcServerOption struct {
+ clientContext opentracing.SpanContext
+}
+
+func (r rpcServerOption) Apply(o *opentracing.StartSpanOptions) {
+ if r.clientContext != nil {
+ opentracing.ChildOf(r.clientContext).Apply(o)
+ }
+ SpanKindRPCServer.Apply(o)
+}
+
+// RPCServerOption returns a StartSpanOption appropriate for an RPC server span
+// with `client` representing the metadata for the remote peer Span if available.
+// In case client == nil, due to the client not being instrumented, this RPC
+// server span will be a root span.
+func RPCServerOption(client opentracing.SpanContext) opentracing.StartSpanOption {
+ return rpcServerOption{client}
+}
+
+// ---
+
+// StringTagName is a common tag name to be set to a string value
+type StringTagName string
+
+// Set adds a string tag to the `span`
+func (tag StringTagName) Set(span opentracing.Span, value string) {
+ span.SetTag(string(tag), value)
+}
+
+// ---
+
+// Uint32TagName is a common tag name to be set to a uint32 value
+type Uint32TagName string
+
+// Set adds a uint32 tag to the `span`
+func (tag Uint32TagName) Set(span opentracing.Span, value uint32) {
+ span.SetTag(string(tag), value)
+}
+
+// ---
+
+// Uint16TagName is a common tag name to be set to a uint16 value
+type Uint16TagName string
+
+// Set adds a uint16 tag to the `span`
+func (tag Uint16TagName) Set(span opentracing.Span, value uint16) {
+ span.SetTag(string(tag), value)
+}
+
+// ---
+
+// BoolTagName is a common tag name to be set to a bool value
+type BoolTagName string
+
+// Set adds a bool tag to the `span`
+func (tag BoolTagName) Set(span opentracing.Span, value bool) {
+ span.SetTag(string(tag), value)
+}
+
+// IPv4TagName is a common tag name to be set to an ipv4 value
+type IPv4TagName string
+
+// Set adds IP v4 host address of the peer as an uint32 value to the `span`, keep this for backward and zipkin compatibility
+func (tag IPv4TagName) Set(span opentracing.Span, value uint32) {
+ span.SetTag(string(tag), value)
+}
+
+// SetString records IP v4 host address of the peer as a .-separated tuple to the `span`. E.g., "127.0.0.1"
+func (tag IPv4TagName) SetString(span opentracing.Span, value string) {
+ span.SetTag(string(tag), value)
+}
diff --git a/vendor/github.com/opentracing/opentracing-go/globaltracer.go b/vendor/github.com/opentracing/opentracing-go/globaltracer.go
new file mode 100644
index 0000000..4f7066a
--- /dev/null
+++ b/vendor/github.com/opentracing/opentracing-go/globaltracer.go
@@ -0,0 +1,42 @@
+package opentracing
+
+type registeredTracer struct {
+ tracer Tracer
+ isRegistered bool
+}
+
+var (
+ globalTracer = registeredTracer{NoopTracer{}, false}
+)
+
+// SetGlobalTracer sets the [singleton] opentracing.Tracer returned by
+// GlobalTracer(). Those who use GlobalTracer (rather than directly manage an
+// opentracing.Tracer instance) should call SetGlobalTracer as early as
+// possible in main(), prior to calling the `StartSpan` global func below.
+// Prior to calling `SetGlobalTracer`, any Spans started via the `StartSpan`
+// (etc) globals are noops.
+func SetGlobalTracer(tracer Tracer) {
+ globalTracer = registeredTracer{tracer, true}
+}
+
+// GlobalTracer returns the global singleton `Tracer` implementation.
+// Before `SetGlobalTracer()` is called, the `GlobalTracer()` is a noop
+// implementation that drops all data handed to it.
+func GlobalTracer() Tracer {
+ return globalTracer.tracer
+}
+
+// StartSpan defers to `Tracer.StartSpan`. See `GlobalTracer()`.
+func StartSpan(operationName string, opts ...StartSpanOption) Span {
+ return globalTracer.tracer.StartSpan(operationName, opts...)
+}
+
+// InitGlobalTracer is deprecated. Please use SetGlobalTracer.
+func InitGlobalTracer(tracer Tracer) {
+ SetGlobalTracer(tracer)
+}
+
+// IsGlobalTracerRegistered returns a `bool` to indicate if a tracer has been globally registered
+func IsGlobalTracerRegistered() bool {
+ return globalTracer.isRegistered
+}
diff --git a/vendor/github.com/opentracing/opentracing-go/go.mod b/vendor/github.com/opentracing/opentracing-go/go.mod
new file mode 100644
index 0000000..bf48bb5
--- /dev/null
+++ b/vendor/github.com/opentracing/opentracing-go/go.mod
@@ -0,0 +1,5 @@
+module github.com/opentracing/opentracing-go
+
+go 1.14
+
+require github.com/stretchr/testify v1.3.0
diff --git a/vendor/github.com/opentracing/opentracing-go/go.sum b/vendor/github.com/opentracing/opentracing-go/go.sum
new file mode 100644
index 0000000..4347755
--- /dev/null
+++ b/vendor/github.com/opentracing/opentracing-go/go.sum
@@ -0,0 +1,7 @@
+github.com/davecgh/go-spew v1.1.0 h1:ZDRjVQ15GmhC3fiQ8ni8+OwkZQO4DARzQgrnXU1Liz8=
+github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+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/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=
diff --git a/vendor/github.com/opentracing/opentracing-go/gocontext.go b/vendor/github.com/opentracing/opentracing-go/gocontext.go
new file mode 100644
index 0000000..1831bc9
--- /dev/null
+++ b/vendor/github.com/opentracing/opentracing-go/gocontext.go
@@ -0,0 +1,65 @@
+package opentracing
+
+import "context"
+
+type contextKey struct{}
+
+var activeSpanKey = contextKey{}
+
+// ContextWithSpan returns a new `context.Context` that holds a reference to
+// the span. If span is nil, a new context without an active span is returned.
+func ContextWithSpan(ctx context.Context, span Span) context.Context {
+ if span != nil {
+ if tracerWithHook, ok := span.Tracer().(TracerContextWithSpanExtension); ok {
+ ctx = tracerWithHook.ContextWithSpanHook(ctx, span)
+ }
+ }
+ return context.WithValue(ctx, activeSpanKey, span)
+}
+
+// SpanFromContext returns the `Span` previously associated with `ctx`, or
+// `nil` if no such `Span` could be found.
+//
+// NOTE: context.Context != SpanContext: the former is Go's intra-process
+// context propagation mechanism, and the latter houses OpenTracing's per-Span
+// identity and baggage information.
+func SpanFromContext(ctx context.Context) Span {
+ val := ctx.Value(activeSpanKey)
+ if sp, ok := val.(Span); ok {
+ return sp
+ }
+ return nil
+}
+
+// StartSpanFromContext starts and returns a Span with `operationName`, using
+// any Span found within `ctx` as a ChildOfRef. If no such parent could be
+// found, StartSpanFromContext creates a root (parentless) Span.
+//
+// The second return value is a context.Context object built around the
+// returned Span.
+//
+// Example usage:
+//
+// SomeFunction(ctx context.Context, ...) {
+// sp, ctx := opentracing.StartSpanFromContext(ctx, "SomeFunction")
+// defer sp.Finish()
+// ...
+// }
+func StartSpanFromContext(ctx context.Context, operationName string, opts ...StartSpanOption) (Span, context.Context) {
+ return StartSpanFromContextWithTracer(ctx, GlobalTracer(), operationName, opts...)
+}
+
+// StartSpanFromContextWithTracer starts and returns a span with `operationName`
+// using a span found within the context as a ChildOfRef. If that doesn't exist
+// it creates a root span. It also returns a context.Context object built
+// around the returned span.
+//
+// It's behavior is identical to StartSpanFromContext except that it takes an explicit
+// tracer as opposed to using the global tracer.
+func StartSpanFromContextWithTracer(ctx context.Context, tracer Tracer, operationName string, opts ...StartSpanOption) (Span, context.Context) {
+ if parentSpan := SpanFromContext(ctx); parentSpan != nil {
+ opts = append(opts, ChildOf(parentSpan.Context()))
+ }
+ span := tracer.StartSpan(operationName, opts...)
+ return span, ContextWithSpan(ctx, span)
+}
diff --git a/vendor/github.com/opentracing/opentracing-go/log/field.go b/vendor/github.com/opentracing/opentracing-go/log/field.go
new file mode 100644
index 0000000..f222ded
--- /dev/null
+++ b/vendor/github.com/opentracing/opentracing-go/log/field.go
@@ -0,0 +1,282 @@
+package log
+
+import (
+ "fmt"
+ "math"
+)
+
+type fieldType int
+
+const (
+ stringType fieldType = iota
+ boolType
+ intType
+ int32Type
+ uint32Type
+ int64Type
+ uint64Type
+ float32Type
+ float64Type
+ errorType
+ objectType
+ lazyLoggerType
+ noopType
+)
+
+// Field instances are constructed via LogBool, LogString, and so on.
+// Tracing implementations may then handle them via the Field.Marshal
+// method.
+//
+// "heavily influenced by" (i.e., partially stolen from)
+// https://github.com/uber-go/zap
+type Field struct {
+ key string
+ fieldType fieldType
+ numericVal int64
+ stringVal string
+ interfaceVal interface{}
+}
+
+// String adds a string-valued key:value pair to a Span.LogFields() record
+func String(key, val string) Field {
+ return Field{
+ key: key,
+ fieldType: stringType,
+ stringVal: val,
+ }
+}
+
+// Bool adds a bool-valued key:value pair to a Span.LogFields() record
+func Bool(key string, val bool) Field {
+ var numericVal int64
+ if val {
+ numericVal = 1
+ }
+ return Field{
+ key: key,
+ fieldType: boolType,
+ numericVal: numericVal,
+ }
+}
+
+// Int adds an int-valued key:value pair to a Span.LogFields() record
+func Int(key string, val int) Field {
+ return Field{
+ key: key,
+ fieldType: intType,
+ numericVal: int64(val),
+ }
+}
+
+// Int32 adds an int32-valued key:value pair to a Span.LogFields() record
+func Int32(key string, val int32) Field {
+ return Field{
+ key: key,
+ fieldType: int32Type,
+ numericVal: int64(val),
+ }
+}
+
+// Int64 adds an int64-valued key:value pair to a Span.LogFields() record
+func Int64(key string, val int64) Field {
+ return Field{
+ key: key,
+ fieldType: int64Type,
+ numericVal: val,
+ }
+}
+
+// Uint32 adds a uint32-valued key:value pair to a Span.LogFields() record
+func Uint32(key string, val uint32) Field {
+ return Field{
+ key: key,
+ fieldType: uint32Type,
+ numericVal: int64(val),
+ }
+}
+
+// Uint64 adds a uint64-valued key:value pair to a Span.LogFields() record
+func Uint64(key string, val uint64) Field {
+ return Field{
+ key: key,
+ fieldType: uint64Type,
+ numericVal: int64(val),
+ }
+}
+
+// Float32 adds a float32-valued key:value pair to a Span.LogFields() record
+func Float32(key string, val float32) Field {
+ return Field{
+ key: key,
+ fieldType: float32Type,
+ numericVal: int64(math.Float32bits(val)),
+ }
+}
+
+// Float64 adds a float64-valued key:value pair to a Span.LogFields() record
+func Float64(key string, val float64) Field {
+ return Field{
+ key: key,
+ fieldType: float64Type,
+ numericVal: int64(math.Float64bits(val)),
+ }
+}
+
+// Error adds an error with the key "error.object" to a Span.LogFields() record
+func Error(err error) Field {
+ return Field{
+ key: "error.object",
+ fieldType: errorType,
+ interfaceVal: err,
+ }
+}
+
+// Object adds an object-valued key:value pair to a Span.LogFields() record
+// Please pass in an immutable object, otherwise there may be concurrency issues.
+// Such as passing in the map, log.Object may result in "fatal error: concurrent map iteration and map write".
+// Because span is sent asynchronously, it is possible that this map will also be modified.
+func Object(key string, obj interface{}) Field {
+ return Field{
+ key: key,
+ fieldType: objectType,
+ interfaceVal: obj,
+ }
+}
+
+// Event creates a string-valued Field for span logs with key="event" and value=val.
+func Event(val string) Field {
+ return String("event", val)
+}
+
+// Message creates a string-valued Field for span logs with key="message" and value=val.
+func Message(val string) Field {
+ return String("message", val)
+}
+
+// LazyLogger allows for user-defined, late-bound logging of arbitrary data
+type LazyLogger func(fv Encoder)
+
+// Lazy adds a LazyLogger to a Span.LogFields() record; the tracing
+// implementation will call the LazyLogger function at an indefinite time in
+// the future (after Lazy() returns).
+func Lazy(ll LazyLogger) Field {
+ return Field{
+ fieldType: lazyLoggerType,
+ interfaceVal: ll,
+ }
+}
+
+// Noop creates a no-op log field that should be ignored by the tracer.
+// It can be used to capture optional fields, for example those that should
+// only be logged in non-production environment:
+//
+// func customerField(order *Order) log.Field {
+// if os.Getenv("ENVIRONMENT") == "dev" {
+// return log.String("customer", order.Customer.ID)
+// }
+// return log.Noop()
+// }
+//
+// span.LogFields(log.String("event", "purchase"), customerField(order))
+//
+func Noop() Field {
+ return Field{
+ fieldType: noopType,
+ }
+}
+
+// Encoder allows access to the contents of a Field (via a call to
+// Field.Marshal).
+//
+// Tracer implementations typically provide an implementation of Encoder;
+// OpenTracing callers typically do not need to concern themselves with it.
+type Encoder interface {
+ EmitString(key, value string)
+ EmitBool(key string, value bool)
+ EmitInt(key string, value int)
+ EmitInt32(key string, value int32)
+ EmitInt64(key string, value int64)
+ EmitUint32(key string, value uint32)
+ EmitUint64(key string, value uint64)
+ EmitFloat32(key string, value float32)
+ EmitFloat64(key string, value float64)
+ EmitObject(key string, value interface{})
+ EmitLazyLogger(value LazyLogger)
+}
+
+// Marshal passes a Field instance through to the appropriate
+// field-type-specific method of an Encoder.
+func (lf Field) Marshal(visitor Encoder) {
+ switch lf.fieldType {
+ case stringType:
+ visitor.EmitString(lf.key, lf.stringVal)
+ case boolType:
+ visitor.EmitBool(lf.key, lf.numericVal != 0)
+ case intType:
+ visitor.EmitInt(lf.key, int(lf.numericVal))
+ case int32Type:
+ visitor.EmitInt32(lf.key, int32(lf.numericVal))
+ case int64Type:
+ visitor.EmitInt64(lf.key, int64(lf.numericVal))
+ case uint32Type:
+ visitor.EmitUint32(lf.key, uint32(lf.numericVal))
+ case uint64Type:
+ visitor.EmitUint64(lf.key, uint64(lf.numericVal))
+ case float32Type:
+ visitor.EmitFloat32(lf.key, math.Float32frombits(uint32(lf.numericVal)))
+ case float64Type:
+ visitor.EmitFloat64(lf.key, math.Float64frombits(uint64(lf.numericVal)))
+ case errorType:
+ if err, ok := lf.interfaceVal.(error); ok {
+ visitor.EmitString(lf.key, err.Error())
+ } else {
+ visitor.EmitString(lf.key, "<nil>")
+ }
+ case objectType:
+ visitor.EmitObject(lf.key, lf.interfaceVal)
+ case lazyLoggerType:
+ visitor.EmitLazyLogger(lf.interfaceVal.(LazyLogger))
+ case noopType:
+ // intentionally left blank
+ }
+}
+
+// Key returns the field's key.
+func (lf Field) Key() string {
+ return lf.key
+}
+
+// Value returns the field's value as interface{}.
+func (lf Field) Value() interface{} {
+ switch lf.fieldType {
+ case stringType:
+ return lf.stringVal
+ case boolType:
+ return lf.numericVal != 0
+ case intType:
+ return int(lf.numericVal)
+ case int32Type:
+ return int32(lf.numericVal)
+ case int64Type:
+ return int64(lf.numericVal)
+ case uint32Type:
+ return uint32(lf.numericVal)
+ case uint64Type:
+ return uint64(lf.numericVal)
+ case float32Type:
+ return math.Float32frombits(uint32(lf.numericVal))
+ case float64Type:
+ return math.Float64frombits(uint64(lf.numericVal))
+ case errorType, objectType, lazyLoggerType:
+ return lf.interfaceVal
+ case noopType:
+ return nil
+ default:
+ return nil
+ }
+}
+
+// String returns a string representation of the key and value.
+func (lf Field) String() string {
+ return fmt.Sprint(lf.key, ":", lf.Value())
+}
diff --git a/vendor/github.com/opentracing/opentracing-go/log/util.go b/vendor/github.com/opentracing/opentracing-go/log/util.go
new file mode 100644
index 0000000..d57e28a
--- /dev/null
+++ b/vendor/github.com/opentracing/opentracing-go/log/util.go
@@ -0,0 +1,61 @@
+package log
+
+import (
+ "fmt"
+ "reflect"
+)
+
+// InterleavedKVToFields converts keyValues a la Span.LogKV() to a Field slice
+// a la Span.LogFields().
+func InterleavedKVToFields(keyValues ...interface{}) ([]Field, error) {
+ if len(keyValues)%2 != 0 {
+ return nil, fmt.Errorf("non-even keyValues len: %d", len(keyValues))
+ }
+ fields := make([]Field, len(keyValues)/2)
+ for i := 0; i*2 < len(keyValues); i++ {
+ key, ok := keyValues[i*2].(string)
+ if !ok {
+ return nil, fmt.Errorf(
+ "non-string key (pair #%d): %T",
+ i, keyValues[i*2])
+ }
+ switch typedVal := keyValues[i*2+1].(type) {
+ case bool:
+ fields[i] = Bool(key, typedVal)
+ case string:
+ fields[i] = String(key, typedVal)
+ case int:
+ fields[i] = Int(key, typedVal)
+ case int8:
+ fields[i] = Int32(key, int32(typedVal))
+ case int16:
+ fields[i] = Int32(key, int32(typedVal))
+ case int32:
+ fields[i] = Int32(key, typedVal)
+ case int64:
+ fields[i] = Int64(key, typedVal)
+ case uint:
+ fields[i] = Uint64(key, uint64(typedVal))
+ case uint64:
+ fields[i] = Uint64(key, typedVal)
+ case uint8:
+ fields[i] = Uint32(key, uint32(typedVal))
+ case uint16:
+ fields[i] = Uint32(key, uint32(typedVal))
+ case uint32:
+ fields[i] = Uint32(key, typedVal)
+ case float32:
+ fields[i] = Float32(key, typedVal)
+ case float64:
+ fields[i] = Float64(key, typedVal)
+ default:
+ if typedVal == nil || (reflect.ValueOf(typedVal).Kind() == reflect.Ptr && reflect.ValueOf(typedVal).IsNil()) {
+ fields[i] = String(key, "nil")
+ continue
+ }
+ // When in doubt, coerce to a string
+ fields[i] = String(key, fmt.Sprint(typedVal))
+ }
+ }
+ return fields, nil
+}
diff --git a/vendor/github.com/opentracing/opentracing-go/noop.go b/vendor/github.com/opentracing/opentracing-go/noop.go
new file mode 100644
index 0000000..f9b680a
--- /dev/null
+++ b/vendor/github.com/opentracing/opentracing-go/noop.go
@@ -0,0 +1,64 @@
+package opentracing
+
+import "github.com/opentracing/opentracing-go/log"
+
+// A NoopTracer is a trivial, minimum overhead implementation of Tracer
+// for which all operations are no-ops.
+//
+// The primary use of this implementation is in libraries, such as RPC
+// frameworks, that make tracing an optional feature controlled by the
+// end user. A no-op implementation allows said libraries to use it
+// as the default Tracer and to write instrumentation that does
+// not need to keep checking if the tracer instance is nil.
+//
+// For the same reason, the NoopTracer is the default "global" tracer
+// (see GlobalTracer and SetGlobalTracer functions).
+//
+// WARNING: NoopTracer does not support baggage propagation.
+type NoopTracer struct{}
+
+type noopSpan struct{}
+type noopSpanContext struct{}
+
+var (
+ defaultNoopSpanContext SpanContext = noopSpanContext{}
+ defaultNoopSpan Span = noopSpan{}
+ defaultNoopTracer Tracer = NoopTracer{}
+)
+
+const (
+ emptyString = ""
+)
+
+// noopSpanContext:
+func (n noopSpanContext) ForeachBaggageItem(handler func(k, v string) bool) {}
+
+// noopSpan:
+func (n noopSpan) Context() SpanContext { return defaultNoopSpanContext }
+func (n noopSpan) SetBaggageItem(key, val string) Span { return n }
+func (n noopSpan) BaggageItem(key string) string { return emptyString }
+func (n noopSpan) SetTag(key string, value interface{}) Span { return n }
+func (n noopSpan) LogFields(fields ...log.Field) {}
+func (n noopSpan) LogKV(keyVals ...interface{}) {}
+func (n noopSpan) Finish() {}
+func (n noopSpan) FinishWithOptions(opts FinishOptions) {}
+func (n noopSpan) SetOperationName(operationName string) Span { return n }
+func (n noopSpan) Tracer() Tracer { return defaultNoopTracer }
+func (n noopSpan) LogEvent(event string) {}
+func (n noopSpan) LogEventWithPayload(event string, payload interface{}) {}
+func (n noopSpan) Log(data LogData) {}
+
+// StartSpan belongs to the Tracer interface.
+func (n NoopTracer) StartSpan(operationName string, opts ...StartSpanOption) Span {
+ return defaultNoopSpan
+}
+
+// Inject belongs to the Tracer interface.
+func (n NoopTracer) Inject(sp SpanContext, format interface{}, carrier interface{}) error {
+ return nil
+}
+
+// Extract belongs to the Tracer interface.
+func (n NoopTracer) Extract(format interface{}, carrier interface{}) (SpanContext, error) {
+ return nil, ErrSpanContextNotFound
+}
diff --git a/vendor/github.com/opentracing/opentracing-go/propagation.go b/vendor/github.com/opentracing/opentracing-go/propagation.go
new file mode 100644
index 0000000..b0c275e
--- /dev/null
+++ b/vendor/github.com/opentracing/opentracing-go/propagation.go
@@ -0,0 +1,176 @@
+package opentracing
+
+import (
+ "errors"
+ "net/http"
+)
+
+///////////////////////////////////////////////////////////////////////////////
+// CORE PROPAGATION INTERFACES:
+///////////////////////////////////////////////////////////////////////////////
+
+var (
+ // ErrUnsupportedFormat occurs when the `format` passed to Tracer.Inject() or
+ // Tracer.Extract() is not recognized by the Tracer implementation.
+ ErrUnsupportedFormat = errors.New("opentracing: Unknown or unsupported Inject/Extract format")
+
+ // ErrSpanContextNotFound occurs when the `carrier` passed to
+ // Tracer.Extract() is valid and uncorrupted but has insufficient
+ // information to extract a SpanContext.
+ ErrSpanContextNotFound = errors.New("opentracing: SpanContext not found in Extract carrier")
+
+ // ErrInvalidSpanContext errors occur when Tracer.Inject() is asked to
+ // operate on a SpanContext which it is not prepared to handle (for
+ // example, since it was created by a different tracer implementation).
+ ErrInvalidSpanContext = errors.New("opentracing: SpanContext type incompatible with tracer")
+
+ // ErrInvalidCarrier errors occur when Tracer.Inject() or Tracer.Extract()
+ // implementations expect a different type of `carrier` than they are
+ // given.
+ ErrInvalidCarrier = errors.New("opentracing: Invalid Inject/Extract carrier")
+
+ // ErrSpanContextCorrupted occurs when the `carrier` passed to
+ // Tracer.Extract() is of the expected type but is corrupted.
+ ErrSpanContextCorrupted = errors.New("opentracing: SpanContext data corrupted in Extract carrier")
+)
+
+///////////////////////////////////////////////////////////////////////////////
+// BUILTIN PROPAGATION FORMATS:
+///////////////////////////////////////////////////////////////////////////////
+
+// BuiltinFormat is used to demarcate the values within package `opentracing`
+// that are intended for use with the Tracer.Inject() and Tracer.Extract()
+// methods.
+type BuiltinFormat byte
+
+const (
+ // Binary represents SpanContexts as opaque binary data.
+ //
+ // For Tracer.Inject(): the carrier must be an `io.Writer`.
+ //
+ // For Tracer.Extract(): the carrier must be an `io.Reader`.
+ Binary BuiltinFormat = iota
+
+ // TextMap represents SpanContexts as key:value string pairs.
+ //
+ // Unlike HTTPHeaders, the TextMap format does not restrict the key or
+ // value character sets in any way.
+ //
+ // For Tracer.Inject(): the carrier must be a `TextMapWriter`.
+ //
+ // For Tracer.Extract(): the carrier must be a `TextMapReader`.
+ TextMap
+
+ // HTTPHeaders represents SpanContexts as HTTP header string pairs.
+ //
+ // Unlike TextMap, the HTTPHeaders format requires that the keys and values
+ // be valid as HTTP headers as-is (i.e., character casing may be unstable
+ // and special characters are disallowed in keys, values should be
+ // URL-escaped, etc).
+ //
+ // For Tracer.Inject(): the carrier must be a `TextMapWriter`.
+ //
+ // For Tracer.Extract(): the carrier must be a `TextMapReader`.
+ //
+ // See HTTPHeadersCarrier for an implementation of both TextMapWriter
+ // and TextMapReader that defers to an http.Header instance for storage.
+ // For example, Inject():
+ //
+ // carrier := opentracing.HTTPHeadersCarrier(httpReq.Header)
+ // err := span.Tracer().Inject(
+ // span.Context(), opentracing.HTTPHeaders, carrier)
+ //
+ // Or Extract():
+ //
+ // carrier := opentracing.HTTPHeadersCarrier(httpReq.Header)
+ // clientContext, err := tracer.Extract(
+ // opentracing.HTTPHeaders, carrier)
+ //
+ HTTPHeaders
+)
+
+// TextMapWriter is the Inject() carrier for the TextMap builtin format. With
+// it, the caller can encode a SpanContext for propagation as entries in a map
+// of unicode strings.
+type TextMapWriter interface {
+ // Set a key:value pair to the carrier. Multiple calls to Set() for the
+ // same key leads to undefined behavior.
+ //
+ // NOTE: The backing store for the TextMapWriter may contain data unrelated
+ // to SpanContext. As such, Inject() and Extract() implementations that
+ // call the TextMapWriter and TextMapReader interfaces must agree on a
+ // prefix or other convention to distinguish their own key:value pairs.
+ Set(key, val string)
+}
+
+// TextMapReader is the Extract() carrier for the TextMap builtin format. With it,
+// the caller can decode a propagated SpanContext as entries in a map of
+// unicode strings.
+type TextMapReader interface {
+ // ForeachKey returns TextMap contents via repeated calls to the `handler`
+ // function. If any call to `handler` returns a non-nil error, ForeachKey
+ // terminates and returns that error.
+ //
+ // NOTE: The backing store for the TextMapReader may contain data unrelated
+ // to SpanContext. As such, Inject() and Extract() implementations that
+ // call the TextMapWriter and TextMapReader interfaces must agree on a
+ // prefix or other convention to distinguish their own key:value pairs.
+ //
+ // The "foreach" callback pattern reduces unnecessary copying in some cases
+ // and also allows implementations to hold locks while the map is read.
+ ForeachKey(handler func(key, val string) error) error
+}
+
+// TextMapCarrier allows the use of regular map[string]string
+// as both TextMapWriter and TextMapReader.
+type TextMapCarrier map[string]string
+
+// ForeachKey conforms to the TextMapReader interface.
+func (c TextMapCarrier) ForeachKey(handler func(key, val string) error) error {
+ for k, v := range c {
+ if err := handler(k, v); err != nil {
+ return err
+ }
+ }
+ return nil
+}
+
+// Set implements Set() of opentracing.TextMapWriter
+func (c TextMapCarrier) Set(key, val string) {
+ c[key] = val
+}
+
+// HTTPHeadersCarrier satisfies both TextMapWriter and TextMapReader.
+//
+// Example usage for server side:
+//
+// carrier := opentracing.HTTPHeadersCarrier(httpReq.Header)
+// clientContext, err := tracer.Extract(opentracing.HTTPHeaders, carrier)
+//
+// Example usage for client side:
+//
+// carrier := opentracing.HTTPHeadersCarrier(httpReq.Header)
+// err := tracer.Inject(
+// span.Context(),
+// opentracing.HTTPHeaders,
+// carrier)
+//
+type HTTPHeadersCarrier http.Header
+
+// Set conforms to the TextMapWriter interface.
+func (c HTTPHeadersCarrier) Set(key, val string) {
+ h := http.Header(c)
+ h.Set(key, val)
+}
+
+// ForeachKey conforms to the TextMapReader interface.
+func (c HTTPHeadersCarrier) ForeachKey(handler func(key, val string) error) error {
+ for k, vals := range c {
+ for _, v := range vals {
+ if err := handler(k, v); err != nil {
+ return err
+ }
+ }
+ }
+ return nil
+}
diff --git a/vendor/github.com/opentracing/opentracing-go/span.go b/vendor/github.com/opentracing/opentracing-go/span.go
new file mode 100644
index 0000000..0d3fb53
--- /dev/null
+++ b/vendor/github.com/opentracing/opentracing-go/span.go
@@ -0,0 +1,189 @@
+package opentracing
+
+import (
+ "time"
+
+ "github.com/opentracing/opentracing-go/log"
+)
+
+// SpanContext represents Span state that must propagate to descendant Spans and across process
+// boundaries (e.g., a <trace_id, span_id, sampled> tuple).
+type SpanContext interface {
+ // ForeachBaggageItem grants access to all baggage items stored in the
+ // SpanContext.
+ // The handler function will be called for each baggage key/value pair.
+ // The ordering of items is not guaranteed.
+ //
+ // The bool return value indicates if the handler wants to continue iterating
+ // through the rest of the baggage items; for example if the handler is trying to
+ // find some baggage item by pattern matching the name, it can return false
+ // as soon as the item is found to stop further iterations.
+ ForeachBaggageItem(handler func(k, v string) bool)
+}
+
+// Span represents an active, un-finished span in the OpenTracing system.
+//
+// Spans are created by the Tracer interface.
+type Span interface {
+ // Sets the end timestamp and finalizes Span state.
+ //
+ // With the exception of calls to Context() (which are always allowed),
+ // Finish() must be the last call made to any span instance, and to do
+ // otherwise leads to undefined behavior.
+ Finish()
+ // FinishWithOptions is like Finish() but with explicit control over
+ // timestamps and log data.
+ FinishWithOptions(opts FinishOptions)
+
+ // Context() yields the SpanContext for this Span. Note that the return
+ // value of Context() is still valid after a call to Span.Finish(), as is
+ // a call to Span.Context() after a call to Span.Finish().
+ Context() SpanContext
+
+ // Sets or changes the operation name.
+ //
+ // Returns a reference to this Span for chaining.
+ SetOperationName(operationName string) Span
+
+ // Adds a tag to the span.
+ //
+ // If there is a pre-existing tag set for `key`, it is overwritten.
+ //
+ // Tag values can be numeric types, strings, or bools. The behavior of
+ // other tag value types is undefined at the OpenTracing level. If a
+ // tracing system does not know how to handle a particular value type, it
+ // may ignore the tag, but shall not panic.
+ //
+ // Returns a reference to this Span for chaining.
+ SetTag(key string, value interface{}) Span
+
+ // LogFields is an efficient and type-checked way to record key:value
+ // logging data about a Span, though the programming interface is a little
+ // more verbose than LogKV(). Here's an example:
+ //
+ // span.LogFields(
+ // log.String("event", "soft error"),
+ // log.String("type", "cache timeout"),
+ // log.Int("waited.millis", 1500))
+ //
+ // Also see Span.FinishWithOptions() and FinishOptions.BulkLogData.
+ LogFields(fields ...log.Field)
+
+ // LogKV is a concise, readable way to record key:value logging data about
+ // a Span, though unfortunately this also makes it less efficient and less
+ // type-safe than LogFields(). Here's an example:
+ //
+ // span.LogKV(
+ // "event", "soft error",
+ // "type", "cache timeout",
+ // "waited.millis", 1500)
+ //
+ // For LogKV (as opposed to LogFields()), the parameters must appear as
+ // key-value pairs, like
+ //
+ // span.LogKV(key1, val1, key2, val2, key3, val3, ...)
+ //
+ // The keys must all be strings. The values may be strings, numeric types,
+ // bools, Go error instances, or arbitrary structs.
+ //
+ // (Note to implementors: consider the log.InterleavedKVToFields() helper)
+ LogKV(alternatingKeyValues ...interface{})
+
+ // SetBaggageItem sets a key:value pair on this Span and its SpanContext
+ // that also propagates to descendants of this Span.
+ //
+ // SetBaggageItem() enables powerful functionality given a full-stack
+ // opentracing integration (e.g., arbitrary application data from a mobile
+ // app can make it, transparently, all the way into the depths of a storage
+ // system), and with it some powerful costs: use this feature with care.
+ //
+ // IMPORTANT NOTE #1: SetBaggageItem() will only propagate baggage items to
+ // *future* causal descendants of the associated Span.
+ //
+ // IMPORTANT NOTE #2: Use this thoughtfully and with care. Every key and
+ // value is copied into every local *and remote* child of the associated
+ // Span, and that can add up to a lot of network and cpu overhead.
+ //
+ // Returns a reference to this Span for chaining.
+ SetBaggageItem(restrictedKey, value string) Span
+
+ // Gets the value for a baggage item given its key. Returns the empty string
+ // if the value isn't found in this Span.
+ BaggageItem(restrictedKey string) string
+
+ // Provides access to the Tracer that created this Span.
+ Tracer() Tracer
+
+ // Deprecated: use LogFields or LogKV
+ LogEvent(event string)
+ // Deprecated: use LogFields or LogKV
+ LogEventWithPayload(event string, payload interface{})
+ // Deprecated: use LogFields or LogKV
+ Log(data LogData)
+}
+
+// LogRecord is data associated with a single Span log. Every LogRecord
+// instance must specify at least one Field.
+type LogRecord struct {
+ Timestamp time.Time
+ Fields []log.Field
+}
+
+// FinishOptions allows Span.FinishWithOptions callers to override the finish
+// timestamp and provide log data via a bulk interface.
+type FinishOptions struct {
+ // FinishTime overrides the Span's finish time, or implicitly becomes
+ // time.Now() if FinishTime.IsZero().
+ //
+ // FinishTime must resolve to a timestamp that's >= the Span's StartTime
+ // (per StartSpanOptions).
+ FinishTime time.Time
+
+ // LogRecords allows the caller to specify the contents of many LogFields()
+ // calls with a single slice. May be nil.
+ //
+ // None of the LogRecord.Timestamp values may be .IsZero() (i.e., they must
+ // be set explicitly). Also, they must be >= the Span's start timestamp and
+ // <= the FinishTime (or time.Now() if FinishTime.IsZero()). Otherwise the
+ // behavior of FinishWithOptions() is undefined.
+ //
+ // If specified, the caller hands off ownership of LogRecords at
+ // FinishWithOptions() invocation time.
+ //
+ // If specified, the (deprecated) BulkLogData must be nil or empty.
+ LogRecords []LogRecord
+
+ // BulkLogData is DEPRECATED.
+ BulkLogData []LogData
+}
+
+// LogData is DEPRECATED
+type LogData struct {
+ Timestamp time.Time
+ Event string
+ Payload interface{}
+}
+
+// ToLogRecord converts a deprecated LogData to a non-deprecated LogRecord
+func (ld *LogData) ToLogRecord() LogRecord {
+ var literalTimestamp time.Time
+ if ld.Timestamp.IsZero() {
+ literalTimestamp = time.Now()
+ } else {
+ literalTimestamp = ld.Timestamp
+ }
+ rval := LogRecord{
+ Timestamp: literalTimestamp,
+ }
+ if ld.Payload == nil {
+ rval.Fields = []log.Field{
+ log.String("event", ld.Event),
+ }
+ } else {
+ rval.Fields = []log.Field{
+ log.String("event", ld.Event),
+ log.Object("payload", ld.Payload),
+ }
+ }
+ return rval
+}
diff --git a/vendor/github.com/opentracing/opentracing-go/tracer.go b/vendor/github.com/opentracing/opentracing-go/tracer.go
new file mode 100644
index 0000000..715f0ce
--- /dev/null
+++ b/vendor/github.com/opentracing/opentracing-go/tracer.go
@@ -0,0 +1,304 @@
+package opentracing
+
+import "time"
+
+// Tracer is a simple, thin interface for Span creation and SpanContext
+// propagation.
+type Tracer interface {
+
+ // Create, start, and return a new Span with the given `operationName` and
+ // incorporate the given StartSpanOption `opts`. (Note that `opts` borrows
+ // from the "functional options" pattern, per
+ // http://dave.cheney.net/2014/10/17/functional-options-for-friendly-apis)
+ //
+ // A Span with no SpanReference options (e.g., opentracing.ChildOf() or
+ // opentracing.FollowsFrom()) becomes the root of its own trace.
+ //
+ // Examples:
+ //
+ // var tracer opentracing.Tracer = ...
+ //
+ // // The root-span case:
+ // sp := tracer.StartSpan("GetFeed")
+ //
+ // // The vanilla child span case:
+ // sp := tracer.StartSpan(
+ // "GetFeed",
+ // opentracing.ChildOf(parentSpan.Context()))
+ //
+ // // All the bells and whistles:
+ // sp := tracer.StartSpan(
+ // "GetFeed",
+ // opentracing.ChildOf(parentSpan.Context()),
+ // opentracing.Tag{"user_agent", loggedReq.UserAgent},
+ // opentracing.StartTime(loggedReq.Timestamp),
+ // )
+ //
+ StartSpan(operationName string, opts ...StartSpanOption) Span
+
+ // Inject() takes the `sm` SpanContext instance and injects it for
+ // propagation within `carrier`. The actual type of `carrier` depends on
+ // the value of `format`.
+ //
+ // OpenTracing defines a common set of `format` values (see BuiltinFormat),
+ // and each has an expected carrier type.
+ //
+ // Other packages may declare their own `format` values, much like the keys
+ // used by `context.Context` (see https://godoc.org/context#WithValue).
+ //
+ // Example usage (sans error handling):
+ //
+ // carrier := opentracing.HTTPHeadersCarrier(httpReq.Header)
+ // err := tracer.Inject(
+ // span.Context(),
+ // opentracing.HTTPHeaders,
+ // carrier)
+ //
+ // NOTE: All opentracing.Tracer implementations MUST support all
+ // BuiltinFormats.
+ //
+ // Implementations may return opentracing.ErrUnsupportedFormat if `format`
+ // is not supported by (or not known by) the implementation.
+ //
+ // Implementations may return opentracing.ErrInvalidCarrier or any other
+ // implementation-specific error if the format is supported but injection
+ // fails anyway.
+ //
+ // See Tracer.Extract().
+ Inject(sm SpanContext, format interface{}, carrier interface{}) error
+
+ // Extract() returns a SpanContext instance given `format` and `carrier`.
+ //
+ // OpenTracing defines a common set of `format` values (see BuiltinFormat),
+ // and each has an expected carrier type.
+ //
+ // Other packages may declare their own `format` values, much like the keys
+ // used by `context.Context` (see
+ // https://godoc.org/golang.org/x/net/context#WithValue).
+ //
+ // Example usage (with StartSpan):
+ //
+ //
+ // carrier := opentracing.HTTPHeadersCarrier(httpReq.Header)
+ // clientContext, err := tracer.Extract(opentracing.HTTPHeaders, carrier)
+ //
+ // // ... assuming the ultimate goal here is to resume the trace with a
+ // // server-side Span:
+ // var serverSpan opentracing.Span
+ // if err == nil {
+ // span = tracer.StartSpan(
+ // rpcMethodName, ext.RPCServerOption(clientContext))
+ // } else {
+ // span = tracer.StartSpan(rpcMethodName)
+ // }
+ //
+ //
+ // NOTE: All opentracing.Tracer implementations MUST support all
+ // BuiltinFormats.
+ //
+ // Return values:
+ // - A successful Extract returns a SpanContext instance and a nil error
+ // - If there was simply no SpanContext to extract in `carrier`, Extract()
+ // returns (nil, opentracing.ErrSpanContextNotFound)
+ // - If `format` is unsupported or unrecognized, Extract() returns (nil,
+ // opentracing.ErrUnsupportedFormat)
+ // - If there are more fundamental problems with the `carrier` object,
+ // Extract() may return opentracing.ErrInvalidCarrier,
+ // opentracing.ErrSpanContextCorrupted, or implementation-specific
+ // errors.
+ //
+ // See Tracer.Inject().
+ Extract(format interface{}, carrier interface{}) (SpanContext, error)
+}
+
+// StartSpanOptions allows Tracer.StartSpan() callers and implementors a
+// mechanism to override the start timestamp, specify Span References, and make
+// a single Tag or multiple Tags available at Span start time.
+//
+// StartSpan() callers should look at the StartSpanOption interface and
+// implementations available in this package.
+//
+// Tracer implementations can convert a slice of `StartSpanOption` instances
+// into a `StartSpanOptions` struct like so:
+//
+// func StartSpan(opName string, opts ...opentracing.StartSpanOption) {
+// sso := opentracing.StartSpanOptions{}
+// for _, o := range opts {
+// o.Apply(&sso)
+// }
+// ...
+// }
+//
+type StartSpanOptions struct {
+ // Zero or more causal references to other Spans (via their SpanContext).
+ // If empty, start a "root" Span (i.e., start a new trace).
+ References []SpanReference
+
+ // StartTime overrides the Span's start time, or implicitly becomes
+ // time.Now() if StartTime.IsZero().
+ StartTime time.Time
+
+ // Tags may have zero or more entries; the restrictions on map values are
+ // identical to those for Span.SetTag(). May be nil.
+ //
+ // If specified, the caller hands off ownership of Tags at
+ // StartSpan() invocation time.
+ Tags map[string]interface{}
+}
+
+// StartSpanOption instances (zero or more) may be passed to Tracer.StartSpan.
+//
+// StartSpanOption borrows from the "functional options" pattern, per
+// http://dave.cheney.net/2014/10/17/functional-options-for-friendly-apis
+type StartSpanOption interface {
+ Apply(*StartSpanOptions)
+}
+
+// SpanReferenceType is an enum type describing different categories of
+// relationships between two Spans. If Span-2 refers to Span-1, the
+// SpanReferenceType describes Span-1 from Span-2's perspective. For example,
+// ChildOfRef means that Span-1 created Span-2.
+//
+// NOTE: Span-1 and Span-2 do *not* necessarily depend on each other for
+// completion; e.g., Span-2 may be part of a background job enqueued by Span-1,
+// or Span-2 may be sitting in a distributed queue behind Span-1.
+type SpanReferenceType int
+
+const (
+ // ChildOfRef refers to a parent Span that caused *and* somehow depends
+ // upon the new child Span. Often (but not always), the parent Span cannot
+ // finish until the child Span does.
+ //
+ // An timing diagram for a ChildOfRef that's blocked on the new Span:
+ //
+ // [-Parent Span---------]
+ // [-Child Span----]
+ //
+ // See http://opentracing.io/spec/
+ //
+ // See opentracing.ChildOf()
+ ChildOfRef SpanReferenceType = iota
+
+ // FollowsFromRef refers to a parent Span that does not depend in any way
+ // on the result of the new child Span. For instance, one might use
+ // FollowsFromRefs to describe pipeline stages separated by queues,
+ // or a fire-and-forget cache insert at the tail end of a web request.
+ //
+ // A FollowsFromRef Span is part of the same logical trace as the new Span:
+ // i.e., the new Span is somehow caused by the work of its FollowsFromRef.
+ //
+ // All of the following could be valid timing diagrams for children that
+ // "FollowFrom" a parent.
+ //
+ // [-Parent Span-] [-Child Span-]
+ //
+ //
+ // [-Parent Span--]
+ // [-Child Span-]
+ //
+ //
+ // [-Parent Span-]
+ // [-Child Span-]
+ //
+ // See http://opentracing.io/spec/
+ //
+ // See opentracing.FollowsFrom()
+ FollowsFromRef
+)
+
+// SpanReference is a StartSpanOption that pairs a SpanReferenceType and a
+// referenced SpanContext. See the SpanReferenceType documentation for
+// supported relationships. If SpanReference is created with
+// ReferencedContext==nil, it has no effect. Thus it allows for a more concise
+// syntax for starting spans:
+//
+// sc, _ := tracer.Extract(someFormat, someCarrier)
+// span := tracer.StartSpan("operation", opentracing.ChildOf(sc))
+//
+// The `ChildOf(sc)` option above will not panic if sc == nil, it will just
+// not add the parent span reference to the options.
+type SpanReference struct {
+ Type SpanReferenceType
+ ReferencedContext SpanContext
+}
+
+// Apply satisfies the StartSpanOption interface.
+func (r SpanReference) Apply(o *StartSpanOptions) {
+ if r.ReferencedContext != nil {
+ o.References = append(o.References, r)
+ }
+}
+
+// ChildOf returns a StartSpanOption pointing to a dependent parent span.
+// If sc == nil, the option has no effect.
+//
+// See ChildOfRef, SpanReference
+func ChildOf(sc SpanContext) SpanReference {
+ return SpanReference{
+ Type: ChildOfRef,
+ ReferencedContext: sc,
+ }
+}
+
+// FollowsFrom returns a StartSpanOption pointing to a parent Span that caused
+// the child Span but does not directly depend on its result in any way.
+// If sc == nil, the option has no effect.
+//
+// See FollowsFromRef, SpanReference
+func FollowsFrom(sc SpanContext) SpanReference {
+ return SpanReference{
+ Type: FollowsFromRef,
+ ReferencedContext: sc,
+ }
+}
+
+// StartTime is a StartSpanOption that sets an explicit start timestamp for the
+// new Span.
+type StartTime time.Time
+
+// Apply satisfies the StartSpanOption interface.
+func (t StartTime) Apply(o *StartSpanOptions) {
+ o.StartTime = time.Time(t)
+}
+
+// Tags are a generic map from an arbitrary string key to an opaque value type.
+// The underlying tracing system is responsible for interpreting and
+// serializing the values.
+type Tags map[string]interface{}
+
+// Apply satisfies the StartSpanOption interface.
+func (t Tags) Apply(o *StartSpanOptions) {
+ if o.Tags == nil {
+ o.Tags = make(map[string]interface{})
+ }
+ for k, v := range t {
+ o.Tags[k] = v
+ }
+}
+
+// Tag may be passed as a StartSpanOption to add a tag to new spans,
+// or its Set method may be used to apply the tag to an existing Span,
+// for example:
+//
+// tracer.StartSpan("opName", Tag{"Key", value})
+//
+// or
+//
+// Tag{"key", value}.Set(span)
+type Tag struct {
+ Key string
+ Value interface{}
+}
+
+// Apply satisfies the StartSpanOption interface.
+func (t Tag) Apply(o *StartSpanOptions) {
+ if o.Tags == nil {
+ o.Tags = make(map[string]interface{})
+ }
+ o.Tags[t.Key] = t.Value
+}
+
+// Set applies the tag to an existing Span.
+func (t Tag) Set(s Span) {
+ s.SetTag(t.Key, t.Value)
+}