gotosocial/vendor/go.opentelemetry.io/otel/exporters/jaeger/jaeger.go
2023-05-09 18:19:48 +01:00

361 lines
9.6 KiB
Go

// 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 jaeger // import "go.opentelemetry.io/otel/exporters/jaeger"
import (
"context"
"encoding/binary"
"encoding/json"
"fmt"
"sync"
"go.opentelemetry.io/otel/attribute"
"go.opentelemetry.io/otel/codes"
gen "go.opentelemetry.io/otel/exporters/jaeger/internal/gen-go/jaeger"
"go.opentelemetry.io/otel/sdk/resource"
sdktrace "go.opentelemetry.io/otel/sdk/trace"
semconv "go.opentelemetry.io/otel/semconv/v1.17.0"
"go.opentelemetry.io/otel/trace"
)
const (
keyInstrumentationLibraryName = "otel.library.name"
keyInstrumentationLibraryVersion = "otel.library.version"
keyError = "error"
keySpanKind = "span.kind"
keyStatusCode = "otel.status_code"
keyStatusMessage = "otel.status_description"
keyDroppedAttributeCount = "otel.event.dropped_attributes_count"
keyEventName = "event"
)
// New returns an OTel Exporter implementation that exports the collected
// spans to Jaeger.
func New(endpointOption EndpointOption) (*Exporter, error) {
uploader, err := endpointOption.newBatchUploader()
if err != nil {
return nil, err
}
// Fetch default service.name from default resource for backup
var defaultServiceName string
defaultResource := resource.Default()
if value, exists := defaultResource.Set().Value(semconv.ServiceNameKey); exists {
defaultServiceName = value.AsString()
}
if defaultServiceName == "" {
return nil, fmt.Errorf("failed to get service name from default resource")
}
stopCh := make(chan struct{})
e := &Exporter{
uploader: uploader,
stopCh: stopCh,
defaultServiceName: defaultServiceName,
}
return e, nil
}
// Exporter exports OpenTelemetry spans to a Jaeger agent or collector.
type Exporter struct {
uploader batchUploader
stopOnce sync.Once
stopCh chan struct{}
defaultServiceName string
}
var _ sdktrace.SpanExporter = (*Exporter)(nil)
// ExportSpans transforms and exports OpenTelemetry spans to Jaeger.
func (e *Exporter) ExportSpans(ctx context.Context, spans []sdktrace.ReadOnlySpan) error {
// Return fast if context is already canceled or Exporter shutdown.
select {
case <-ctx.Done():
return ctx.Err()
case <-e.stopCh:
return nil
default:
}
// Cancel export if Exporter is shutdown.
var cancel context.CancelFunc
ctx, cancel = context.WithCancel(ctx)
defer cancel()
go func(ctx context.Context, cancel context.CancelFunc) {
select {
case <-ctx.Done():
case <-e.stopCh:
cancel()
}
}(ctx, cancel)
for _, batch := range jaegerBatchList(spans, e.defaultServiceName) {
if err := e.uploader.upload(ctx, batch); err != nil {
return err
}
}
return nil
}
// Shutdown stops the Exporter. This will close all connections and release
// all resources held by the Exporter.
func (e *Exporter) Shutdown(ctx context.Context) error {
// Stop any active and subsequent exports.
e.stopOnce.Do(func() { close(e.stopCh) })
select {
case <-ctx.Done():
return ctx.Err()
default:
}
return e.uploader.shutdown(ctx)
}
// MarshalLog is the marshaling function used by the logging system to represent this exporter.
func (e *Exporter) MarshalLog() interface{} {
return struct {
Type string
}{
Type: "jaeger",
}
}
func spanToThrift(ss sdktrace.ReadOnlySpan) *gen.Span {
attr := ss.Attributes()
tags := make([]*gen.Tag, 0, len(attr))
for _, kv := range attr {
tag := keyValueToTag(kv)
if tag != nil {
tags = append(tags, tag)
}
}
if is := ss.InstrumentationScope(); is.Name != "" {
tags = append(tags, getStringTag(keyInstrumentationLibraryName, is.Name))
if is.Version != "" {
tags = append(tags, getStringTag(keyInstrumentationLibraryVersion, is.Version))
}
}
if ss.SpanKind() != trace.SpanKindInternal {
tags = append(tags,
getStringTag(keySpanKind, ss.SpanKind().String()),
)
}
if ss.Status().Code != codes.Unset {
switch ss.Status().Code {
case codes.Ok:
tags = append(tags, getStringTag(keyStatusCode, "OK"))
case codes.Error:
tags = append(tags, getBoolTag(keyError, true))
tags = append(tags, getStringTag(keyStatusCode, "ERROR"))
}
if ss.Status().Description != "" {
tags = append(tags, getStringTag(keyStatusMessage, ss.Status().Description))
}
}
var logs []*gen.Log
for _, a := range ss.Events() {
nTags := len(a.Attributes)
if a.Name != "" {
nTags++
}
if a.DroppedAttributeCount != 0 {
nTags++
}
fields := make([]*gen.Tag, 0, nTags)
if a.Name != "" {
// If an event contains an attribute with the same key, it needs
// to be given precedence and overwrite this.
fields = append(fields, getStringTag(keyEventName, a.Name))
}
for _, kv := range a.Attributes {
tag := keyValueToTag(kv)
if tag != nil {
fields = append(fields, tag)
}
}
if a.DroppedAttributeCount != 0 {
fields = append(fields, getInt64Tag(keyDroppedAttributeCount, int64(a.DroppedAttributeCount)))
}
logs = append(logs, &gen.Log{
Timestamp: a.Time.UnixNano() / 1000,
Fields: fields,
})
}
var refs []*gen.SpanRef
for _, link := range ss.Links() {
tid := link.SpanContext.TraceID()
sid := link.SpanContext.SpanID()
refs = append(refs, &gen.SpanRef{
TraceIdHigh: int64(binary.BigEndian.Uint64(tid[0:8])),
TraceIdLow: int64(binary.BigEndian.Uint64(tid[8:16])),
SpanId: int64(binary.BigEndian.Uint64(sid[:])),
RefType: gen.SpanRefType_FOLLOWS_FROM,
})
}
tid := ss.SpanContext().TraceID()
sid := ss.SpanContext().SpanID()
psid := ss.Parent().SpanID()
return &gen.Span{
TraceIdHigh: int64(binary.BigEndian.Uint64(tid[0:8])),
TraceIdLow: int64(binary.BigEndian.Uint64(tid[8:16])),
SpanId: int64(binary.BigEndian.Uint64(sid[:])),
ParentSpanId: int64(binary.BigEndian.Uint64(psid[:])),
OperationName: ss.Name(), // TODO: if span kind is added then add prefix "Sent"/"Recv"
Flags: int32(ss.SpanContext().TraceFlags()),
StartTime: ss.StartTime().UnixNano() / 1000,
Duration: ss.EndTime().Sub(ss.StartTime()).Nanoseconds() / 1000,
Tags: tags,
Logs: logs,
References: refs,
}
}
func keyValueToTag(keyValue attribute.KeyValue) *gen.Tag {
var tag *gen.Tag
switch keyValue.Value.Type() {
case attribute.STRING:
s := keyValue.Value.AsString()
tag = &gen.Tag{
Key: string(keyValue.Key),
VStr: &s,
VType: gen.TagType_STRING,
}
case attribute.BOOL:
b := keyValue.Value.AsBool()
tag = &gen.Tag{
Key: string(keyValue.Key),
VBool: &b,
VType: gen.TagType_BOOL,
}
case attribute.INT64:
i := keyValue.Value.AsInt64()
tag = &gen.Tag{
Key: string(keyValue.Key),
VLong: &i,
VType: gen.TagType_LONG,
}
case attribute.FLOAT64:
f := keyValue.Value.AsFloat64()
tag = &gen.Tag{
Key: string(keyValue.Key),
VDouble: &f,
VType: gen.TagType_DOUBLE,
}
case attribute.BOOLSLICE,
attribute.INT64SLICE,
attribute.FLOAT64SLICE,
attribute.STRINGSLICE:
data, _ := json.Marshal(keyValue.Value.AsInterface())
a := (string)(data)
tag = &gen.Tag{
Key: string(keyValue.Key),
VStr: &a,
VType: gen.TagType_STRING,
}
}
return tag
}
func getInt64Tag(k string, i int64) *gen.Tag {
return &gen.Tag{
Key: k,
VLong: &i,
VType: gen.TagType_LONG,
}
}
func getStringTag(k, s string) *gen.Tag {
return &gen.Tag{
Key: k,
VStr: &s,
VType: gen.TagType_STRING,
}
}
func getBoolTag(k string, b bool) *gen.Tag {
return &gen.Tag{
Key: k,
VBool: &b,
VType: gen.TagType_BOOL,
}
}
// jaegerBatchList transforms a slice of spans into a slice of jaeger Batch.
func jaegerBatchList(ssl []sdktrace.ReadOnlySpan, defaultServiceName string) []*gen.Batch {
if len(ssl) == 0 {
return nil
}
batchDict := make(map[attribute.Distinct]*gen.Batch)
for _, ss := range ssl {
if ss == nil {
continue
}
resourceKey := ss.Resource().Equivalent()
batch, bOK := batchDict[resourceKey]
if !bOK {
batch = &gen.Batch{
Process: process(ss.Resource(), defaultServiceName),
Spans: []*gen.Span{},
}
}
batch.Spans = append(batch.Spans, spanToThrift(ss))
batchDict[resourceKey] = batch
}
// Transform the categorized map into a slice
batchList := make([]*gen.Batch, 0, len(batchDict))
for _, batch := range batchDict {
batchList = append(batchList, batch)
}
return batchList
}
// process transforms an OTel Resource into a jaeger Process.
func process(res *resource.Resource, defaultServiceName string) *gen.Process {
var process gen.Process
var serviceName attribute.KeyValue
if res != nil {
for iter := res.Iter(); iter.Next(); {
if iter.Attribute().Key == semconv.ServiceNameKey {
serviceName = iter.Attribute()
// Don't convert service.name into tag.
continue
}
if tag := keyValueToTag(iter.Attribute()); tag != nil {
process.Tags = append(process.Tags, tag)
}
}
}
// If no service.name is contained in a Span's Resource,
// that field MUST be populated from the default Resource.
if serviceName.Value.AsString() == "" {
serviceName = semconv.ServiceName(defaultServiceName)
}
process.ServiceName = serviceName.Value.AsString()
return &process
}