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diff --git a/vendor/github.com/opentracing/opentracing-go/LICENSE b/vendor/github.com/opentracing/opentracing-go/LICENSE new file mode 100644 index 000000000..f0027349e --- /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, + and distribution as defined by Sections 1 through 9 of this document. + + "Licensor" shall mean the copyright owner or entity authorized by + the copyright owner that is granting the License. + + "Legal Entity" shall mean the union of the acting entity and all + other entities that control, are controlled by, or are under common + control with that entity. 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We also recommend that a + file or class name and description of purpose be included on the + same "printed page" as the copyright notice for easier + identification within third-party archives. + + 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, + WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + See the License for the specific language governing permissions and + limitations under the License. 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 000000000..6ef1d7c9d --- /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/tags.go b/vendor/github.com/opentracing/opentracing-go/ext/tags.go new file mode 100644 index 000000000..52e889582 --- /dev/null +++ b/vendor/github.com/opentracing/opentracing-go/ext/tags.go @@ -0,0 +1,210 @@ +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 of + // 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 = ipv4Tag("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} +} + +// --- + +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) +} + +// --- + +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) +} + +// --- + +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) +} + +// --- + +type boolTagName string + +// Add adds a bool tag to the `span` +func (tag boolTagName) Set(span opentracing.Span, value bool) { + span.SetTag(string(tag), value) +} + +type ipv4Tag 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 ipv4Tag) 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 ipv4Tag) 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 000000000..4f7066a92 --- /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/gocontext.go b/vendor/github.com/opentracing/opentracing-go/gocontext.go new file mode 100644 index 000000000..05a62e70b --- /dev/null +++ b/vendor/github.com/opentracing/opentracing-go/gocontext.go @@ -0,0 +1,54 @@ +package opentracing + +import "context" + +type contextKey struct{} + +var activeSpanKey = contextKey{} + +// ContextWithSpan returns a new `context.Context` that holds a reference to +// `span`'s SpanContext. +func ContextWithSpan(ctx context.Context, span Span) context.Context { + 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 is factored out for testing purposes. +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 000000000..50feea341 --- /dev/null +++ b/vendor/github.com/opentracing/opentracing-go/log/field.go @@ -0,0 +1,269 @@ +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" to a Span.LogFields() record +func Error(err error) Field { + return Field{ + key: "error", + fieldType: errorType, + interfaceVal: err, + } +} + +// Object adds an object-valued key:value pair to a Span.LogFields() record +func Object(key string, obj interface{}) Field { + return Field{ + key: key, + fieldType: objectType, + interfaceVal: obj, + } +} + +// 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 000000000..3832feb5c --- /dev/null +++ b/vendor/github.com/opentracing/opentracing-go/log/util.go @@ -0,0 +1,54 @@ +package log + +import "fmt" + +// 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: + // 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 000000000..0d32f692c --- /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 = noopSpanContext{} + defaultNoopSpan = noopSpan{} + defaultNoopTracer = 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 defaultNoopSpan } +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 000000000..b0c275eb0 --- /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 000000000..0d3fb5341 --- /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 000000000..7bca1f736 --- /dev/null +++ b/vendor/github.com/opentracing/opentracing-go/tracer.go @@ -0,0 +1,305 @@ +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/golang.org/x/net/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) +} |