forked from TrueCloudLab/distribution
4b14eef595
The new context package supports context-aware logging, integrating with logrus. Several utilities are provided to associate http requests with a context, ensuring that one can trace log messages all the way through a context-aware call stack. A full description of this functionality is available in doc.go. Signed-off-by: Stephen J Day <stephen.day@docker.com>
34 lines
834 B
Go
34 lines
834 B
Go
package context
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import (
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"time"
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"golang.org/x/net/context"
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)
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// Since looks up key, which should be a time.Time, and returns the duration
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// since that time. If the key is not found, the value returned will be zero.
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// This is helpful when inferring metrics related to context execution times.
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func Since(ctx context.Context, key interface{}) time.Duration {
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startedAtI := ctx.Value(key)
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if startedAtI != nil {
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if startedAt, ok := startedAtI.(time.Time); ok {
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return time.Since(startedAt)
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}
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}
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return 0
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}
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// GetStringValue returns a string value from the context. The empty string
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// will be returned if not found.
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func GetStringValue(ctx context.Context, key string) (value string) {
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stringi := ctx.Value(key)
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if stringi != nil {
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if valuev, ok := stringi.(string); ok {
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value = valuev
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}
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}
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return value
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}
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