com.cloudera.gertrude

Class ExperimentHandler

java.lang.Object

com.cloudera.gertrude.ExperimentHandler

public final class ExperimentHandler
extends Object

Manages experiment diversion for an ExperimentState based on the data contained in the current ExperimentSpace.

The handler is the link between an ExperimentState and the currently configured ExperimentSpace. As new requests are passed to the handle(AbstractExperimentState) method, the ExperimentHandler diverts them into experiments that modifies their flag value calculators that are used for the rest of the request by calling the ExperimentState.get(ExperimentFlag) methods:

   static ExperimentFlag<Boolean> AWESOME_FEATURE_ON = Experiments.declare("awesome", false);
 public void doStuff(Request request) {
    MyExperimentState state = new MyExperimentState(request);
    Experiments.getHandler().handle(state);
    if (state.get(AWESOME_FEATURE_ON)) {
      // enable *AWESOME* feature
    } else {
      // enable feature suggested by product manager
    }
 }

New ExperimentSpace configurations may be updated asynchronously by the ExperimentSpaceLoader that is configured for use with this ExperimentHandler in the Experiments namespace. Subsequent calls to the handle(AbstractExperimentState) method will use the latest updates to the ExperimentSpace for processing requests, and the ExperimentHandler is thread-safe.

Method Summary

Methods

Modifier and Type	Method and Description
boolean	disable(int experimentId) Disables the experiment with the given id, preventing it from diverting any traffic.
String	getVersionIdentifier() Returns the version string for the ExperimentSpace that is currently being used by this instance to handle requests.
void	handle(AbstractExperimentState state) Diverts the given ExperimentState into one or more experiments across the Layer instances in the current ExperimentSpace.

Methods inherited from class java.lang.Object

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

Method Detail

handle

public void handle(AbstractExperimentState state)

Diverts the given ExperimentState into one or more experiments across the Layer instances in the current ExperimentSpace.

A given ExperimentState can only be diverted into one experiment per layer; attempting to re-divert an instance that has already been diverted has no effect on the flag values or experiment ids associated with the state.

Parameters:

state - the request to divert

disable

public boolean disable(int experimentId)

Disables the experiment with the given id, preventing it from diverting any traffic.

Parameters:

experimentId - id of the experiment to disable

Returns:

true if the experiment was found and disabled, false otherwise

getVersionIdentifier

public String getVersionIdentifier()

Returns the version string for the ExperimentSpace that is currently being used by this instance to handle requests.

Returns:

the version string for the current ExperimentSpace