github.com/erda-project/erda-infra@v1.0.10-0.20240327085753-f3a249292aeb/pkg/trace/inject/http-client/http_client.go (about)

     1  // Copyright (c) 2021 Terminus, Inc.
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //      http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  package traceinject
    16  
    17  import (
    18  	"net/http"
    19  	_ "unsafe" //nolint
    20  
    21  	"go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp"
    22  	"go.opentelemetry.io/otel/trace"
    23  
    24  	injectcontext "github.com/erda-project/erda-infra/pkg/trace/inject/context"
    25  	"github.com/erda-project/erda-infra/pkg/trace/inject/hook"
    26  )
    27  
    28  // RoundTrip .
    29  //
    30  //go:linkname RoundTrip net/http.(*Transport).RoundTrip
    31  //go:noinline
    32  func RoundTrip(t *http.Transport, req *http.Request) (*http.Response, error)
    33  
    34  //go:noinline
    35  func originalRoundTrip(t *http.Transport, req *http.Request) (*http.Response, error) {
    36  	return RoundTrip(t, req)
    37  }
    38  
    39  type wrappedTransport struct {
    40  	t *http.Transport
    41  }
    42  
    43  //go:noinline
    44  func (t *wrappedTransport) RoundTrip(req *http.Request) (*http.Response, error) {
    45  	return originalRoundTrip(t.t, req)
    46  }
    47  
    48  //go:noinline
    49  func tracedRoundTrip(t *http.Transport, req *http.Request) (*http.Response, error) {
    50  	req = contextWithSpan(req)
    51  	return otelhttp.NewTransport(&wrappedTransport{t: t}).RoundTrip(req)
    52  }
    53  
    54  //go:noinline
    55  func contextWithSpan(req *http.Request) *http.Request {
    56  	ctx := req.Context()
    57  	if span := trace.SpanFromContext(ctx); !span.SpanContext().IsValid() {
    58  		pctx := injectcontext.GetContext()
    59  		if pctx != nil {
    60  			if span := trace.SpanFromContext(pctx); span.SpanContext().IsValid() {
    61  				ctx = trace.ContextWithSpan(ctx, span)
    62  				req = req.WithContext(ctx)
    63  			}
    64  		}
    65  	}
    66  	return req
    67  }
    68  
    69  func init() {
    70  	hook.Hook(RoundTrip, tracedRoundTrip, originalRoundTrip)
    71  }