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Diffstat (limited to 'vendor/go.opentelemetry.io/otel/internal/baggage/context.go')
-rw-r--r--vendor/go.opentelemetry.io/otel/internal/baggage/context.go92
1 files changed, 92 insertions, 0 deletions
diff --git a/vendor/go.opentelemetry.io/otel/internal/baggage/context.go b/vendor/go.opentelemetry.io/otel/internal/baggage/context.go
new file mode 100644
index 000000000..4469700d9
--- /dev/null
+++ b/vendor/go.opentelemetry.io/otel/internal/baggage/context.go
@@ -0,0 +1,92 @@
+// 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 baggage // import "go.opentelemetry.io/otel/internal/baggage"
+
+import "context"
+
+type baggageContextKeyType int
+
+const baggageKey baggageContextKeyType = iota
+
+// SetHookFunc is a callback called when storing baggage in the context.
+type SetHookFunc func(context.Context, List) context.Context
+
+// GetHookFunc is a callback called when getting baggage from the context.
+type GetHookFunc func(context.Context, List) List
+
+type baggageState struct {
+ list List
+
+ setHook SetHookFunc
+ getHook GetHookFunc
+}
+
+// ContextWithSetHook returns a copy of parent with hook configured to be
+// invoked every time ContextWithBaggage is called.
+//
+// Passing nil SetHookFunc creates a context with no set hook to call.
+func ContextWithSetHook(parent context.Context, hook SetHookFunc) context.Context {
+ var s baggageState
+ if v, ok := parent.Value(baggageKey).(baggageState); ok {
+ s = v
+ }
+
+ s.setHook = hook
+ return context.WithValue(parent, baggageKey, s)
+}
+
+// ContextWithGetHook returns a copy of parent with hook configured to be
+// invoked every time FromContext is called.
+//
+// Passing nil GetHookFunc creates a context with no get hook to call.
+func ContextWithGetHook(parent context.Context, hook GetHookFunc) context.Context {
+ var s baggageState
+ if v, ok := parent.Value(baggageKey).(baggageState); ok {
+ s = v
+ }
+
+ s.getHook = hook
+ return context.WithValue(parent, baggageKey, s)
+}
+
+// ContextWithList returns a copy of parent with baggage. Passing nil list
+// returns a context without any baggage.
+func ContextWithList(parent context.Context, list List) context.Context {
+ var s baggageState
+ if v, ok := parent.Value(baggageKey).(baggageState); ok {
+ s = v
+ }
+
+ s.list = list
+ ctx := context.WithValue(parent, baggageKey, s)
+ if s.setHook != nil {
+ ctx = s.setHook(ctx, list)
+ }
+
+ return ctx
+}
+
+// ListFromContext returns the baggage contained in ctx.
+func ListFromContext(ctx context.Context) List {
+ switch v := ctx.Value(baggageKey).(type) {
+ case baggageState:
+ if v.getHook != nil {
+ return v.getHook(ctx, v.list)
+ }
+ return v.list
+ default:
+ return nil
+ }
+}