com.flipkart.poseidon.tracing

Class DynamicSampleRateTraceFilter

java.lang.Object

com.flipkart.poseidon.tracing.DynamicSampleRateTraceFilter

All Implemented Interfaces:

com.github.kristofa.brave.TraceFilter

public class DynamicSampleRateTraceFilter
extends Object
implements com.github.kristofa.brave.TraceFilter

DynamicSampleRateTraceFilter is an implementation of TraceFilter that determines whether to trace requests using TracingConfiguration.

Globally tracing can be turned on/off by using config flag TracingConfiguration.enableTracing(). Once tracing is turned on globally, tracing for individual URLs can be controlled using map config TracingConfiguration.getSampleRateMap(). It is read only when global tracing is toggled from off to on. Once the config is read, it won't be reloaded until global tracing is switched off and on again. Current sampling counter per URL is kept in an instance of FixedSampleRateTraceFilter which shouldn't be reconstructed for every request. Hence we avoid reading this config once read into memory.

Ex: To turn on tracing for all requests, use

TracingConfiguration.enableTracing() should return true
TracingConfiguration.getSampleRateMap() should return {"*": 1}

To turn on tracing for only some URLs, say 1 out of 100 "/some_api" and 1 out of 50 "/some_other_api" requests should be traced and to turn off for all other URLs, use

TracingConfiguration.enableTracing() should return true
TracingConfiguration.getSampleRateMap() should return {"/some_api": 100, "/some_other_api": 50}

Version:

1.0, 15th Jul, 2015

Author:

Mohan Kumar Pandian

Constructor Summary

Constructors

Constructor and Description
DynamicSampleRateTraceFilter(TracingConfiguration tracingConfiguration)

Method Summary

Modifier and Type	Method and Description
void	close()
boolean	trace(String requestName)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

DynamicSampleRateTraceFilter

public DynamicSampleRateTraceFilter(TracingConfiguration tracingConfiguration)

Method Detail

trace

public boolean trace(String requestName)

Specified by:

trace in interface com.github.kristofa.brave.TraceFilter

close

public void close()

Specified by:

close in interface com.github.kristofa.brave.TraceFilter