Hook execution sequence issue

[krutsko]

1. Expected onComplete to be executed in all cases at the very end.
2. in testExecutionHookRunFailureWithFallback - onComplete executed twice.

PR to demo that #327

Hook lifecycle captured during run of tests coming with Hystrix Core (version 1.3.9):
{noformat}
testExecutionHookSuccessfulCommand (execute):
onStart - onThreadStart - onRunStart - onRunSuccess - onComplete - onThreadComplete -

testExecutionHookSuccessfulCommand (queue)
onStart - onThreadStart - onRunStart - onRunSuccess - onComplete - onThreadComplete -

testExecutionHookSuccessfulCommandViaFireAndForget
onStart - onThreadStart - onRunStart - onRunSuccess - onComplete - onThreadComplete -

testExecutionHookSuccessfulCommandWithMultipleGetsOnFuture
onStart - onThreadStart - onRunStart - onRunSuccess - onComplete - onThreadComplete -

testExecutionHookRunFailureWithoutFallback
onStart - onThreadStart - onRunStart - *** simulated failed execution *** - onRunError - onFallbackStart - onFallbackError - onError - onThreadComplete -

testExecutionHookRunFailureWithFallback
onStart - onThreadStart - onRunStart - *** simulated failed execution *** - onRunError - onFallbackStart - onFallbackSuccess - onComplete - onComplete - onThreadComplete -

testExecutionHookRunFailureWithFallbackFailure
onStart - onThreadStart - onRunStart - *** simulated failed execution *** - onRunError - onFallbackStart - onFallbackError - onError - onThreadComplete -

testExecutionHookTimeoutWithoutFallback
onStart - onThreadStart - onRunStart - ***** running - onFallbackStart - onFallbackError - onError - after interruption with extra sleep
onRunSuccess - onThreadComplete -

testExecutionHookTimeoutWithFallback
onStart - onThreadStart - onRunStart - ***** running - onFallbackStart - onFallbackSuccess - onComplete - after interruption with extra sleep - onRunSuccess - onThreadComplete -

testExecutionHookRejectedWithFallback
onStart - onFallbackStart - onFallbackSuccess - onComplete

testExecutionHookShortCircuitedWithFallbackViaQueue
onStart - onFallbackStart - onFallbackError - onError -

testExecutionHookShortCircuitedWithFallbackViaExecute
onStart - onFallbackStart - onFallbackError - onError -

testExecutionHookSuccessfulCommandWithSemaphoreIsolation
onStart - onRunStart - onRunSuccess - onComplete -

testExecutionHookFailureWithSemaphoreIsolation
onStart - onFallbackStart - onFallbackError - onError -

testExecutionHookFailedOnHystrixBadRequestWithSemaphoreIsolation:
onStart - onRunStart - *** simulated failed execution ***onRunError -
{noformat}

[benjchristensen]

1. Expected onComplete to be executed in all cases at the very end.

onComplete is the successful termination event. onError is the failure termination event.

As per the Javadoc:

onComplete: Invoked after completion of {@link HystrixCommand} execution that results in a response.
onError: Invoked after failed completion of {@link HystrixCommand} execution.

2. in testExecutionHookRunFailureWithFallback - onComplete executed twice.

Will need to look into that.

[pparth]

@benjchristensen can you explain please why onComplete is raised before onThreadComplete, whereas onThreadStart is raised after onStart?

[benjchristensen]

Because onThreadComplete happens AFTER (try/finally) it has returned the value back to the main thread which returns to the user and completes thus calling onComplete. onThreadStart happens AFTER the command has started.

[krutsko]

@benjchristensen please also take a look at
testExecutionHookFailedOnHystrixBadRequestWithSemaphoreIsolation
Expected : onStart - onRunStart - onRunError - onError -
Actual :onStart - onRunStart - onRunError -

[mattrjacobs]

I think this is now resolved via #378 and a new issue opened around onThreadComplete work in #377