grpc-go/stats/opentelemetry/server_tracing.go

47 lines
1.9 KiB
Go

/*
* Copyright 2024 gRPC 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 opentelemetry
import (
"context"
"strings"
"go.opentelemetry.io/otel"
"go.opentelemetry.io/otel/trace"
otelinternaltracing "google.golang.org/grpc/stats/opentelemetry/internal/tracing"
)
// traceTagRPC populates context with new span data using the TextMapPropagator
// supplied in trace options and internal itracing.Carrier. It creates a new
// incoming carrier which extracts an existing span context (if present) by
// deserializing from provided context. If valid span context is extracted, it
// is set as parent of the new span otherwise new span remains the root span.
// If TextMapPropagator is not provided in the trace options, it returns context
// as is.
func (h *serverStatsHandler) traceTagRPC(ctx context.Context, ai *attemptInfo) (context.Context, *attemptInfo) {
mn := strings.Replace(ai.method, "/", ".", -1)
var span trace.Span
tracer := otel.Tracer("grpc-open-telemetry")
ctx = otel.GetTextMapPropagator().Extract(ctx, otelinternaltracing.NewIncomingCarrier(ctx))
// If the context.Context provided in `ctx` to tracer.Start(), contains a
// span then the newly-created Span will be a child of that span,
// otherwise it will be a root span.
ctx, span = tracer.Start(ctx, mn, trace.WithSpanKind(trace.SpanKindServer))
ai.traceSpan = span
return ctx, ai
}