49 lines
993 B
Go
49 lines
993 B
Go
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// Package trace provides an interface for distributed tracing
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package trace
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import (
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"context"
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"time"
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)
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// Trace is an interface for distributed tracing
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type Trace interface {
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// Start a trace
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Start(ctx context.Context, name string) *Span
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// Finish the trace
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Finish(*Span) error
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// Read the traces
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Read(...ReadOption) ([]*Span, error)
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}
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// Span is used to record an entry
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type Span struct {
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// Id of the trace
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Trace string
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// name of the span
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Name string
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// id of the span
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Id string
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// parent span id
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Parent string
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// Start time
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Started time.Time
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// Finish time
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Finished time.Time
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// associated data
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Metadata map[string]string
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}
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type spanKey struct{}
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// FromContext returns a span from context
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func FromContext(ctx context.Context) (*Span, bool) {
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s, ok := ctx.Value(spanKey{}).(*Span)
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return s, ok
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}
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// NewContext creates a new context with the span
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func NewContext(ctx context.Context, s *Span) context.Context {
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return context.WithValue(ctx, spanKey{}, s)
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}
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