44 lines
		
	
	
		
			865 B
		
	
	
	
		
			Go
		
	
	
	
	
	
			
		
		
	
	
			44 lines
		
	
	
		
			865 B
		
	
	
	
		
			Go
		
	
	
	
	
	
package meter
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import (
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	"context"
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)
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type meterKey struct{}
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// FromContext get meter from context
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func FromContext(ctx context.Context) (Meter, bool) {
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	if ctx == nil {
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		return nil, false
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	}
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	c, ok := ctx.Value(meterKey{}).(Meter)
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	return c, ok
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}
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// MustContext get meter from context
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func MustContext(ctx context.Context) Meter {
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	m, ok := FromContext(ctx)
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	if !ok {
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		panic("missing meter")
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	}
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	return m
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}
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// NewContext put meter in context
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func NewContext(ctx context.Context, c Meter) context.Context {
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	if ctx == nil {
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		ctx = context.Background()
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	}
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	return context.WithValue(ctx, meterKey{}, c)
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}
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// SetOption returns a function to setup a context with given value
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func SetOption(k, v interface{}) Option {
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	return func(o *Options) {
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		if o.Context == nil {
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			o.Context = context.Background()
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		}
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		o.Context = context.WithValue(o.Context, k, v)
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	}
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}
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