39 lines
1.2 KiB
Go
39 lines
1.2 KiB
Go
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package hclog
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import (
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"context"
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)
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// WithContext inserts a logger into the context and is retrievable
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// with FromContext. The optional args can be set with the same syntax as
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// Logger.With to set fields on the inserted logger. This will not modify
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// the logger argument in-place.
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func WithContext(ctx context.Context, logger Logger, args ...interface{}) context.Context {
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// While we could call logger.With even with zero args, we have this
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// check to avoid unnecessary allocations around creating a copy of a
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// logger.
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if len(args) > 0 {
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logger = logger.With(args...)
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}
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return context.WithValue(ctx, contextKey, logger)
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}
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// FromContext returns a logger from the context. This will return L()
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// (the default logger) if no logger is found in the context. Therefore,
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// this will never return a nil value.
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func FromContext(ctx context.Context) Logger {
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logger, _ := ctx.Value(contextKey).(Logger)
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if logger == nil {
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return L()
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}
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return logger
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}
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// Unexported new type so that our context key never collides with another.
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type contextKeyType struct{}
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// contextKey is the key used for the context to store the logger.
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var contextKey = contextKeyType{}
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