30 lines
488 B
Go
30 lines
488 B
Go
package context
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import (
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"golang.org/x/net/context"
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)
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type key int
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const (
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mdKey = key(0)
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)
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type Metadata map[string]string
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func GetMetadata(ctx context.Context) (Metadata, bool) {
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md, ok := ctx.Value(mdKey).(Metadata)
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return md, ok
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}
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func WithMetadata(ctx context.Context, md Metadata) context.Context {
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if emd, ok := ctx.Value(mdKey).(Metadata); ok {
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for k, v := range emd {
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if _, ok := md[k]; !ok {
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md[k] = v
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}
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}
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}
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return context.WithValue(ctx, mdKey, md)
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}
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