prometheus/vendor/github.com/opentracing/opentracing-go/globaltracer.go
Tom Wilkie 4d9b917d11 Instrument Prometheus with OpenTracing (#2554)
* Use request.Context() instead of a global map of contexts.

* Add some basic opentracing instrumentation on the query path.

* Remove tracehandler endpoint.
2017-05-02 18:49:29 -05:00

33 lines
1.1 KiB
Go

package opentracing
var (
globalTracer Tracer = NoopTracer{}
)
// SetGlobalTracer sets the [singleton] opentracing.Tracer returned by
// GlobalTracer(). Those who use GlobalTracer (rather than directly manage an
// opentracing.Tracer instance) should call SetGlobalTracer as early as
// possible in main(), prior to calling the `StartSpan` global func below.
// Prior to calling `SetGlobalTracer`, any Spans started via the `StartSpan`
// (etc) globals are noops.
func SetGlobalTracer(tracer Tracer) {
globalTracer = tracer
}
// GlobalTracer returns the global singleton `Tracer` implementation.
// Before `SetGlobalTracer()` is called, the `GlobalTracer()` is a noop
// implementation that drops all data handed to it.
func GlobalTracer() Tracer {
return globalTracer
}
// StartSpan defers to `Tracer.StartSpan`. See `GlobalTracer()`.
func StartSpan(operationName string, opts ...StartSpanOption) Span {
return globalTracer.StartSpan(operationName, opts...)
}
// InitGlobalTracer is deprecated. Please use SetGlobalTracer.
func InitGlobalTracer(tracer Tracer) {
SetGlobalTracer(tracer)
}