diff options
Diffstat (limited to 'vendor/go.opentelemetry.io/otel/trace/trace.go')
| -rw-r--r-- | vendor/go.opentelemetry.io/otel/trace/trace.go | 551 |
1 files changed, 551 insertions, 0 deletions
diff --git a/vendor/go.opentelemetry.io/otel/trace/trace.go b/vendor/go.opentelemetry.io/otel/trace/trace.go new file mode 100644 index 000000000..4aa94f79f --- /dev/null +++ b/vendor/go.opentelemetry.io/otel/trace/trace.go @@ -0,0 +1,551 @@ +// Copyright The OpenTelemetry 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. + +package trace // import "go.opentelemetry.io/otel/trace" + +import ( + "bytes" + "context" + "encoding/hex" + "encoding/json" + + "go.opentelemetry.io/otel/attribute" + "go.opentelemetry.io/otel/codes" +) + +const ( + // FlagsSampled is a bitmask with the sampled bit set. A SpanContext + // with the sampling bit set means the span is sampled. + FlagsSampled = TraceFlags(0x01) + + errInvalidHexID errorConst = "trace-id and span-id can only contain [0-9a-f] characters, all lowercase" + + errInvalidTraceIDLength errorConst = "hex encoded trace-id must have length equals to 32" + errNilTraceID errorConst = "trace-id can't be all zero" + + errInvalidSpanIDLength errorConst = "hex encoded span-id must have length equals to 16" + errNilSpanID errorConst = "span-id can't be all zero" +) + +type errorConst string + +func (e errorConst) Error() string { + return string(e) +} + +// TraceID is a unique identity of a trace. +// nolint:revive // revive complains about stutter of `trace.TraceID`. +type TraceID [16]byte + +var nilTraceID TraceID +var _ json.Marshaler = nilTraceID + +// IsValid checks whether the trace TraceID is valid. A valid trace ID does +// not consist of zeros only. +func (t TraceID) IsValid() bool { + return !bytes.Equal(t[:], nilTraceID[:]) +} + +// MarshalJSON implements a custom marshal function to encode TraceID +// as a hex string. +func (t TraceID) MarshalJSON() ([]byte, error) { + return json.Marshal(t.String()) +} + +// String returns the hex string representation form of a TraceID. +func (t TraceID) String() string { + return hex.EncodeToString(t[:]) +} + +// SpanID is a unique identity of a span in a trace. +type SpanID [8]byte + +var nilSpanID SpanID +var _ json.Marshaler = nilSpanID + +// IsValid checks whether the SpanID is valid. A valid SpanID does not consist +// of zeros only. +func (s SpanID) IsValid() bool { + return !bytes.Equal(s[:], nilSpanID[:]) +} + +// MarshalJSON implements a custom marshal function to encode SpanID +// as a hex string. +func (s SpanID) MarshalJSON() ([]byte, error) { + return json.Marshal(s.String()) +} + +// String returns the hex string representation form of a SpanID. +func (s SpanID) String() string { + return hex.EncodeToString(s[:]) +} + +// TraceIDFromHex returns a TraceID from a hex string if it is compliant with +// the W3C trace-context specification. See more at +// https://www.w3.org/TR/trace-context/#trace-id +// nolint:revive // revive complains about stutter of `trace.TraceIDFromHex`. +func TraceIDFromHex(h string) (TraceID, error) { + t := TraceID{} + if len(h) != 32 { + return t, errInvalidTraceIDLength + } + + if err := decodeHex(h, t[:]); err != nil { + return t, err + } + + if !t.IsValid() { + return t, errNilTraceID + } + return t, nil +} + +// SpanIDFromHex returns a SpanID from a hex string if it is compliant +// with the w3c trace-context specification. +// See more at https://www.w3.org/TR/trace-context/#parent-id +func SpanIDFromHex(h string) (SpanID, error) { + s := SpanID{} + if len(h) != 16 { + return s, errInvalidSpanIDLength + } + + if err := decodeHex(h, s[:]); err != nil { + return s, err + } + + if !s.IsValid() { + return s, errNilSpanID + } + return s, nil +} + +func decodeHex(h string, b []byte) error { + for _, r := range h { + switch { + case 'a' <= r && r <= 'f': + continue + case '0' <= r && r <= '9': + continue + default: + return errInvalidHexID + } + } + + decoded, err := hex.DecodeString(h) + if err != nil { + return err + } + + copy(b, decoded) + return nil +} + +// TraceFlags contains flags that can be set on a SpanContext. +type TraceFlags byte //nolint:revive // revive complains about stutter of `trace.TraceFlags`. + +// IsSampled returns if the sampling bit is set in the TraceFlags. +func (tf TraceFlags) IsSampled() bool { + return tf&FlagsSampled == FlagsSampled +} + +// WithSampled sets the sampling bit in a new copy of the TraceFlags. +func (tf TraceFlags) WithSampled(sampled bool) TraceFlags { // nolint:revive // sampled is not a control flag. + if sampled { + return tf | FlagsSampled + } + + return tf &^ FlagsSampled +} + +// MarshalJSON implements a custom marshal function to encode TraceFlags +// as a hex string. +func (tf TraceFlags) MarshalJSON() ([]byte, error) { + return json.Marshal(tf.String()) +} + +// String returns the hex string representation form of TraceFlags. +func (tf TraceFlags) String() string { + return hex.EncodeToString([]byte{byte(tf)}[:]) +} + +// SpanContextConfig contains mutable fields usable for constructing +// an immutable SpanContext. +type SpanContextConfig struct { + TraceID TraceID + SpanID SpanID + TraceFlags TraceFlags + TraceState TraceState + Remote bool +} + +// NewSpanContext constructs a SpanContext using values from the provided +// SpanContextConfig. +func NewSpanContext(config SpanContextConfig) SpanContext { + return SpanContext{ + traceID: config.TraceID, + spanID: config.SpanID, + traceFlags: config.TraceFlags, + traceState: config.TraceState, + remote: config.Remote, + } +} + +// SpanContext contains identifying trace information about a Span. +type SpanContext struct { + traceID TraceID + spanID SpanID + traceFlags TraceFlags + traceState TraceState + remote bool +} + +var _ json.Marshaler = SpanContext{} + +// IsValid returns if the SpanContext is valid. A valid span context has a +// valid TraceID and SpanID. +func (sc SpanContext) IsValid() bool { + return sc.HasTraceID() && sc.HasSpanID() +} + +// IsRemote indicates whether the SpanContext represents a remotely-created Span. +func (sc SpanContext) IsRemote() bool { + return sc.remote +} + +// WithRemote returns a copy of sc with the Remote property set to remote. +func (sc SpanContext) WithRemote(remote bool) SpanContext { + return SpanContext{ + traceID: sc.traceID, + spanID: sc.spanID, + traceFlags: sc.traceFlags, + traceState: sc.traceState, + remote: remote, + } +} + +// TraceID returns the TraceID from the SpanContext. +func (sc SpanContext) TraceID() TraceID { + return sc.traceID +} + +// HasTraceID checks if the SpanContext has a valid TraceID. +func (sc SpanContext) HasTraceID() bool { + return sc.traceID.IsValid() +} + +// WithTraceID returns a new SpanContext with the TraceID replaced. +func (sc SpanContext) WithTraceID(traceID TraceID) SpanContext { + return SpanContext{ + traceID: traceID, + spanID: sc.spanID, + traceFlags: sc.traceFlags, + traceState: sc.traceState, + remote: sc.remote, + } +} + +// SpanID returns the SpanID from the SpanContext. +func (sc SpanContext) SpanID() SpanID { + return sc.spanID +} + +// HasSpanID checks if the SpanContext has a valid SpanID. +func (sc SpanContext) HasSpanID() bool { + return sc.spanID.IsValid() +} + +// WithSpanID returns a new SpanContext with the SpanID replaced. +func (sc SpanContext) WithSpanID(spanID SpanID) SpanContext { + return SpanContext{ + traceID: sc.traceID, + spanID: spanID, + traceFlags: sc.traceFlags, + traceState: sc.traceState, + remote: sc.remote, + } +} + +// TraceFlags returns the flags from the SpanContext. +func (sc SpanContext) TraceFlags() TraceFlags { + return sc.traceFlags +} + +// IsSampled returns if the sampling bit is set in the SpanContext's TraceFlags. +func (sc SpanContext) IsSampled() bool { + return sc.traceFlags.IsSampled() +} + +// WithTraceFlags returns a new SpanContext with the TraceFlags replaced. +func (sc SpanContext) WithTraceFlags(flags TraceFlags) SpanContext { + return SpanContext{ + traceID: sc.traceID, + spanID: sc.spanID, + traceFlags: flags, + traceState: sc.traceState, + remote: sc.remote, + } +} + +// TraceState returns the TraceState from the SpanContext. +func (sc SpanContext) TraceState() TraceState { + return sc.traceState +} + +// WithTraceState returns a new SpanContext with the TraceState replaced. +func (sc SpanContext) WithTraceState(state TraceState) SpanContext { + return SpanContext{ + traceID: sc.traceID, + spanID: sc.spanID, + traceFlags: sc.traceFlags, + traceState: state, + remote: sc.remote, + } +} + +// Equal is a predicate that determines whether two SpanContext values are equal. +func (sc SpanContext) Equal(other SpanContext) bool { + return sc.traceID == other.traceID && + sc.spanID == other.spanID && + sc.traceFlags == other.traceFlags && + sc.traceState.String() == other.traceState.String() && + sc.remote == other.remote +} + +// MarshalJSON implements a custom marshal function to encode a SpanContext. +func (sc SpanContext) MarshalJSON() ([]byte, error) { + return json.Marshal(SpanContextConfig{ + TraceID: sc.traceID, + SpanID: sc.spanID, + TraceFlags: sc.traceFlags, + TraceState: sc.traceState, + Remote: sc.remote, + }) +} + +// Span is the individual component of a trace. It represents a single named +// and timed operation of a workflow that is traced. A Tracer is used to +// create a Span and it is then up to the operation the Span represents to +// properly end the Span when the operation itself ends. +// +// Warning: methods may be added to this interface in minor releases. +type Span interface { + // End completes the Span. The Span is considered complete and ready to be + // delivered through the rest of the telemetry pipeline after this method + // is called. Therefore, updates to the Span are not allowed after this + // method has been called. + End(options ...SpanEndOption) + + // AddEvent adds an event with the provided name and options. + AddEvent(name string, options ...EventOption) + + // IsRecording returns the recording state of the Span. It will return + // true if the Span is active and events can be recorded. + IsRecording() bool + + // RecordError will record err as an exception span event for this span. An + // additional call to SetStatus is required if the Status of the Span should + // be set to Error, as this method does not change the Span status. If this + // span is not being recorded or err is nil then this method does nothing. + RecordError(err error, options ...EventOption) + + // SpanContext returns the SpanContext of the Span. The returned SpanContext + // is usable even after the End method has been called for the Span. + SpanContext() SpanContext + + // SetStatus sets the status of the Span in the form of a code and a + // description, provided the status hasn't already been set to a higher + // value before (OK > Error > Unset). The description is only included in a + // status when the code is for an error. + SetStatus(code codes.Code, description string) + + // SetName sets the Span name. + SetName(name string) + + // SetAttributes sets kv as attributes of the Span. If a key from kv + // already exists for an attribute of the Span it will be overwritten with + // the value contained in kv. + SetAttributes(kv ...attribute.KeyValue) + + // TracerProvider returns a TracerProvider that can be used to generate + // additional Spans on the same telemetry pipeline as the current Span. + TracerProvider() TracerProvider +} + +// Link is the relationship between two Spans. The relationship can be within +// the same Trace or across different Traces. +// +// For example, a Link is used in the following situations: +// +// 1. Batch Processing: A batch of operations may contain operations +// associated with one or more traces/spans. Since there can only be one +// parent SpanContext, a Link is used to keep reference to the +// SpanContext of all operations in the batch. +// 2. Public Endpoint: A SpanContext for an in incoming client request on a +// public endpoint should be considered untrusted. In such a case, a new +// trace with its own identity and sampling decision needs to be created, +// but this new trace needs to be related to the original trace in some +// form. A Link is used to keep reference to the original SpanContext and +// track the relationship. +type Link struct { + // SpanContext of the linked Span. + SpanContext SpanContext + + // Attributes describe the aspects of the link. + Attributes []attribute.KeyValue +} + +// LinkFromContext returns a link encapsulating the SpanContext in the provided ctx. +func LinkFromContext(ctx context.Context, attrs ...attribute.KeyValue) Link { + return Link{ + SpanContext: SpanContextFromContext(ctx), + Attributes: attrs, + } +} + +// SpanKind is the role a Span plays in a Trace. +type SpanKind int + +// As a convenience, these match the proto definition, see +// https://github.com/open-telemetry/opentelemetry-proto/blob/30d237e1ff3ab7aa50e0922b5bebdd93505090af/opentelemetry/proto/trace/v1/trace.proto#L101-L129 +// +// The unspecified value is not a valid `SpanKind`. Use `ValidateSpanKind()` +// to coerce a span kind to a valid value. +const ( + // SpanKindUnspecified is an unspecified SpanKind and is not a valid + // SpanKind. SpanKindUnspecified should be replaced with SpanKindInternal + // if it is received. + SpanKindUnspecified SpanKind = 0 + // SpanKindInternal is a SpanKind for a Span that represents an internal + // operation within an application. + SpanKindInternal SpanKind = 1 + // SpanKindServer is a SpanKind for a Span that represents the operation + // of handling a request from a client. + SpanKindServer SpanKind = 2 + // SpanKindClient is a SpanKind for a Span that represents the operation + // of client making a request to a server. + SpanKindClient SpanKind = 3 + // SpanKindProducer is a SpanKind for a Span that represents the operation + // of a producer sending a message to a message broker. Unlike + // SpanKindClient and SpanKindServer, there is often no direct + // relationship between this kind of Span and a SpanKindConsumer kind. A + // SpanKindProducer Span will end once the message is accepted by the + // message broker which might not overlap with the processing of that + // message. + SpanKindProducer SpanKind = 4 + // SpanKindConsumer is a SpanKind for a Span that represents the operation + // of a consumer receiving a message from a message broker. Like + // SpanKindProducer Spans, there is often no direct relationship between + // this Span and the Span that produced the message. + SpanKindConsumer SpanKind = 5 +) + +// ValidateSpanKind returns a valid span kind value. This will coerce +// invalid values into the default value, SpanKindInternal. +func ValidateSpanKind(spanKind SpanKind) SpanKind { + switch spanKind { + case SpanKindInternal, + SpanKindServer, + SpanKindClient, + SpanKindProducer, + SpanKindConsumer: + // valid + return spanKind + default: + return SpanKindInternal + } +} + +// String returns the specified name of the SpanKind in lower-case. +func (sk SpanKind) String() string { + switch sk { + case SpanKindInternal: + return "internal" + case SpanKindServer: + return "server" + case SpanKindClient: + return "client" + case SpanKindProducer: + return "producer" + case SpanKindConsumer: + return "consumer" + default: + return "unspecified" + } +} + +// Tracer is the creator of Spans. +// +// Warning: methods may be added to this interface in minor releases. +type Tracer interface { + // Start creates a span and a context.Context containing the newly-created span. + // + // If the context.Context provided in `ctx` contains a Span then the newly-created + // Span will be a child of that span, otherwise it will be a root span. This behavior + // can be overridden by providing `WithNewRoot()` as a SpanOption, causing the + // newly-created Span to be a root span even if `ctx` contains a Span. + // + // When creating a Span it is recommended to provide all known span attributes using + // the `WithAttributes()` SpanOption as samplers will only have access to the + // attributes provided when a Span is created. + // + // Any Span that is created MUST also be ended. This is the responsibility of the user. + // Implementations of this API may leak memory or other resources if Spans are not ended. + Start(ctx context.Context, spanName string, opts ...SpanStartOption) (context.Context, Span) +} + +// TracerProvider provides Tracers that are used by instrumentation code to +// trace computational workflows. +// +// A TracerProvider is the collection destination of all Spans from Tracers it +// provides, it represents a unique telemetry collection pipeline. How that +// pipeline is defined, meaning how those Spans are collected, processed, and +// where they are exported, depends on its implementation. Instrumentation +// authors do not need to define this implementation, rather just use the +// provided Tracers to instrument code. +// +// Commonly, instrumentation code will accept a TracerProvider implementation +// at runtime from its users or it can simply use the globally registered one +// (see https://pkg.go.dev/go.opentelemetry.io/otel#GetTracerProvider). +// +// Warning: methods may be added to this interface in minor releases. +type TracerProvider interface { + // Tracer returns a unique Tracer scoped to be used by instrumentation code + // to trace computational workflows. The scope and identity of that + // instrumentation code is uniquely defined by the name and options passed. + // + // The passed name needs to uniquely identify instrumentation code. + // Therefore, it is recommended that name is the Go package name of the + // library providing instrumentation (note: not the code being + // instrumented). Instrumentation libraries can have multiple versions, + // therefore, the WithInstrumentationVersion option should be used to + // distinguish these different codebases. Additionally, instrumentation + // libraries may sometimes use traces to communicate different domains of + // workflow data (i.e. using spans to communicate workflow events only). If + // this is the case, the WithScopeAttributes option should be used to + // uniquely identify Tracers that handle the different domains of workflow + // data. + // + // If the same name and options are passed multiple times, the same Tracer + // will be returned (it is up to the implementation if this will be the + // same underlying instance of that Tracer or not). It is not necessary to + // call this multiple times with the same name and options to get an + // up-to-date Tracer. All implementations will ensure any TracerProvider + // configuration changes are propagated to all provided Tracers. + // + // If name is empty, then an implementation defined default name will be + // used instead. + // + // This method is safe to call concurrently. + Tracer(name string, options ...TracerOption) Tracer +} |