mirror of https://github.com/knative/pkg.git
54 lines
1.7 KiB
Go
54 lines
1.7 KiB
Go
/*
|
|
Copyright 2020 The Knative 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 propagation
|
|
|
|
import (
|
|
"net/http"
|
|
|
|
"go.opencensus.io/trace"
|
|
"go.opencensus.io/trace/propagation"
|
|
)
|
|
|
|
// HTTPFormatSequence is a propagation.HTTPFormat that applies multiple other propagation formats.
|
|
// For incoming requests, it will use the first SpanContext it can find, checked in the order of
|
|
// HTTPFormatSequence.Ingress.
|
|
// For outgoing requests, it will apply all the formats to the outgoing request, in the order of
|
|
// HTTPFormatSequence.Egress.
|
|
type HTTPFormatSequence struct {
|
|
Ingress []propagation.HTTPFormat
|
|
Egress []propagation.HTTPFormat
|
|
}
|
|
|
|
var _ propagation.HTTPFormat = (*HTTPFormatSequence)(nil)
|
|
|
|
// SpanContextFromRequest satisfies the propagation.HTTPFormat interface.
|
|
func (h *HTTPFormatSequence) SpanContextFromRequest(req *http.Request) (trace.SpanContext, bool) {
|
|
for _, format := range h.Ingress {
|
|
if sc, ok := format.SpanContextFromRequest(req); ok {
|
|
return sc, true
|
|
}
|
|
}
|
|
return trace.SpanContext{}, false
|
|
}
|
|
|
|
// SpanContextToRequest satisfies the propagation.HTTPFormat interface.
|
|
func (h *HTTPFormatSequence) SpanContextToRequest(sc trace.SpanContext, req *http.Request) {
|
|
for _, format := range h.Egress {
|
|
format.SpanContextToRequest(sc, req)
|
|
}
|
|
}
|