blob: fe0c5d9e96631a35731def04e9822634e550441a [file] [log] [blame]
// Copyright 2017, OpenCensus 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 tag_test
import (
"context"
"log"
"go.opencensus.io/tag"
)
var (
tagMap *tag.Map
ctx context.Context
key tag.Key
)
func ExampleNewKey() {
// Get a key to represent user OS.
key, err := tag.NewKey("example.com/keys/user-os")
if err != nil {
log.Fatal(err)
}
_ = key // use key
}
func ExampleNew() {
osKey, err := tag.NewKey("example.com/keys/user-os")
if err != nil {
log.Fatal(err)
}
userIDKey, err := tag.NewKey("example.com/keys/user-id")
if err != nil {
log.Fatal(err)
}
ctx, err := tag.New(ctx,
tag.Insert(osKey, "macOS-10.12.5"),
tag.Upsert(userIDKey, "cde36753ed"),
)
if err != nil {
log.Fatal(err)
}
_ = ctx // use context
}
func ExampleNew_replace() {
ctx, err := tag.New(ctx,
tag.Insert(key, "macOS-10.12.5"),
tag.Upsert(key, "macOS-10.12.7"),
)
if err != nil {
log.Fatal(err)
}
_ = ctx // use context
}
func ExampleNewContext() {
// Propagate the tag map in the current context.
ctx := tag.NewContext(context.Background(), tagMap)
_ = ctx // use context
}
func ExampleFromContext() {
tagMap := tag.FromContext(ctx)
_ = tagMap // use the tag map
}
func ExampleDo() {
ctx, err := tag.New(ctx,
tag.Insert(key, "macOS-10.12.5"),
tag.Upsert(key, "macOS-10.12.7"),
)
if err != nil {
log.Fatal(err)
}
tag.Do(ctx, func(ctx context.Context) {
_ = ctx // use context
})
}