A promise library compatible with [Medium's kew promises library](https://github.com/Medium/kew) with support added for LightStep OpenTracing instrumentation.
npm install traced-kewA promise library compatible with Medium's kew promises library with support added for LightStep OpenTracing instrumentation.
Compatibility-note: the library implementation currently relies on several LightStep-specific methods and is not compatible with all OpenTracing tracer implementations.
* Getting started
* Demo
* API
``bash`
npm install --save traced-kew
Initialize the OpenTracing global tracer (the library currently uses the OpenTracing global tracer for all operations):
`javascript`
Tracer.initGlobalTracer(LightStep.tracer({
access_token : '{your_access_token}',
component_name : 'kew-example',
}));
Use the library as you would use the kew library:
`javascript
import Q from 'traced-kew';
Q.all([
Q.delay(50),
Q.delay(20),
]).then(() => {
console.log('Done!');
});
`
Use the traced version of the various kew methods to add OpenTracing tracing annotations:
`javascript
import Q from 'traced-kew';
// Start a span to track the chained promises
let span = Tracer.startSpan('Q.all');
Q.tracedAll(span, [
Q.tracedDelay('a delay of 50ms', span, 50),
Q.tracedDelay('a delay of 20ms', span, 20),
]).tracedThen((span) => {
span.logEvent('The promises have resolved!');
console.log('Done!');
})
.finish(); // Let the library know the chaining is done
`
:success_parrot:
The access_token values in the examples need to be updated to your project's access token, then the following can be run:
`
make demo-ok # Makes a trace with only successful operations
make demo-fail # Makes a trace containing spans with errors
#### Trace for the resolved promises
#### Trace for the rejected promises
* Static methods
* all(promises), tracedAll(span, promises)
*
* , tracedDefer(name, parentSpan)
* , tracedDelay(name, parent, ms)
fcall is not yet implemented*
isPromise is not yet implemented*
isPromiseLike is not yet implemented*
ncall is not yet implemented*
nfcall is not yet implemented*
*
*
*
*
*
*
*
* Instance methods
* , tracedFail(function(span, reason))
* , tracedFin(function(span))
*
* , tracedSpread(span, …args)
*
*
* , tracedThen(function(span, result))
*
*
`
make test