1 files changed, 161 insertions, 0 deletions
diff --git a/vendor/go.opentelemetry.io/otel/sdk/trace/tracer.go b/vendor/go.opentelemetry.io/otel/sdk/trace/tracer.go
new file mode 100644
index 000000000..f17d924b8
--- /dev/null
+++ b/vendor/go.opentelemetry.io/otel/sdk/trace/tracer.go
@@ -0,0 +1,161 @@
+// 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/sdk/trace"
+
+import (
+	"context"
+	"time"
+
+	"go.opentelemetry.io/otel/sdk/instrumentation"
+	"go.opentelemetry.io/otel/trace"
+)
+
+type tracer struct {
+	provider             *TracerProvider
+	instrumentationScope instrumentation.Scope
+}
+
+var _ trace.Tracer = &tracer{}
+
+// Start starts a Span and returns it along with a context containing it.
+//
+// The Span is created with the provided name and as a child of any existing
+// span context found in the passed context. The created Span will be
+// configured appropriately by any SpanOption passed.
+func (tr *tracer) Start(ctx context.Context, name string, options ...trace.SpanStartOption) (context.Context, trace.Span) {
+	config := trace.NewSpanStartConfig(options...)
+
+	if ctx == nil {
+		// Prevent trace.ContextWithSpan from panicking.
+		ctx = context.Background()
+	}
+
+	// For local spans created by this SDK, track child span count.
+	if p := trace.SpanFromContext(ctx); p != nil {
+		if sdkSpan, ok := p.(*recordingSpan); ok {
+			sdkSpan.addChild()
+		}
+	}
+
+	s := tr.newSpan(ctx, name, &config)
+	if rw, ok := s.(ReadWriteSpan); ok && s.IsRecording() {
+		sps := tr.provider.spanProcessors.Load().(spanProcessorStates)
+		for _, sp := range sps {
+			sp.sp.OnStart(ctx, rw)
+		}
+	}
+	if rtt, ok := s.(runtimeTracer); ok {
+		ctx = rtt.runtimeTrace(ctx)
+	}
+
+	return trace.ContextWithSpan(ctx, s), s
+}
+
+type runtimeTracer interface {
+	// runtimeTrace starts a "runtime/trace".Task for the span and
+	// returns a context containing the task.
+	runtimeTrace(ctx context.Context) context.Context
+}
+
+// newSpan returns a new configured span.
+func (tr *tracer) newSpan(ctx context.Context, name string, config *trace.SpanConfig) trace.Span {
+	// If told explicitly to make this a new root use a zero value SpanContext
+	// as a parent which contains an invalid trace ID and is not remote.
+	var psc trace.SpanContext
+	if config.NewRoot() {
+		ctx = trace.ContextWithSpanContext(ctx, psc)
+	} else {
+		psc = trace.SpanContextFromContext(ctx)
+	}
+
+	// If there is a valid parent trace ID, use it to ensure the continuity of
+	// the trace. Always generate a new span ID so other components can rely
+	// on a unique span ID, even if the Span is non-recording.
+	var tid trace.TraceID
+	var sid trace.SpanID
+	if !psc.TraceID().IsValid() {
+		tid, sid = tr.provider.idGenerator.NewIDs(ctx)
+	} else {
+		tid = psc.TraceID()
+		sid = tr.provider.idGenerator.NewSpanID(ctx, tid)
+	}
+
+	samplingResult := tr.provider.sampler.ShouldSample(SamplingParameters{
+		ParentContext: ctx,
+		TraceID:       tid,
+		Name:          name,
+		Kind:          config.SpanKind(),
+		Attributes:    config.Attributes(),
+		Links:         config.Links(),
+	})
+
+	scc := trace.SpanContextConfig{
+		TraceID:    tid,
+		SpanID:     sid,
+		TraceState: samplingResult.Tracestate,
+	}
+	if isSampled(samplingResult) {
+		scc.TraceFlags = psc.TraceFlags() | trace.FlagsSampled
+	} else {
+		scc.TraceFlags = psc.TraceFlags() &^ trace.FlagsSampled
+	}
+	sc := trace.NewSpanContext(scc)
+
+	if !isRecording(samplingResult) {
+		return tr.newNonRecordingSpan(sc)
+	}
+	return tr.newRecordingSpan(psc, sc, name, samplingResult, config)
+}
+
+// newRecordingSpan returns a new configured recordingSpan.
+func (tr *tracer) newRecordingSpan(psc, sc trace.SpanContext, name string, sr SamplingResult, config *trace.SpanConfig) *recordingSpan {
+	startTime := config.Timestamp()
+	if startTime.IsZero() {
+		startTime = time.Now()
+	}
+
+	s := &recordingSpan{
+		// Do not pre-allocate the attributes slice here! Doing so will
+		// allocate memory that is likely never going to be used, or if used,
+		// will be over-sized. The default Go compiler has been tested to
+		// dynamically allocate needed space very well. Benchmarking has shown
+		// it to be more performant than what we can predetermine here,
+		// especially for the common use case of few to no added
+		// attributes.
+
+		parent:      psc,
+		spanContext: sc,
+		spanKind:    trace.ValidateSpanKind(config.SpanKind()),
+		name:        name,
+		startTime:   startTime,
+		events:      newEvictedQueue(tr.provider.spanLimits.EventCountLimit),
+		links:       newEvictedQueue(tr.provider.spanLimits.LinkCountLimit),
+		tracer:      tr,
+	}
+
+	for _, l := range config.Links() {
+		s.addLink(l)
+	}
+
+	s.SetAttributes(sr.Attributes...)
+	s.SetAttributes(config.Attributes()...)
+
+	return s
+}
+
+// newNonRecordingSpan returns a new configured nonRecordingSpan.
+func (tr *tracer) newNonRecordingSpan(sc trace.SpanContext) nonRecordingSpan {
+	return nonRecordingSpan{tracer: tr, sc: sc}
+}