Exception returns successfully

[jpbarto]

When setting 'failureMode' to 'exception' the Lambda function returns successfully, an exception occurs but the Lambda function succeeds.

START RequestId: 303ca17f-a63c-44ce-a38e-9236e3db57c2 Version: $LATEST
2020-02-07T14:18:14.839Z	303ca17f-a63c-44ce-a38e-9236e3db57c2	INFO	Injecting exception message: Exception message!
2020-02-07T14:18:14.852Z	303ca17f-a63c-44ce-a38e-9236e3db57c2	INFO	Error: Exception message!
    at Runtime.handler (/var/task/node_modules/failure-lambda/lib/failure.js:31:17)
    at processTicksAndRejections (internal/process/task_queues.js:93:5)END RequestId: 303ca17f-a63c-44ce-a38e-9236e3db57c2
REPORT RequestId: 303ca17f-a63c-44ce-a38e-9236e3db57c2	Duration: 142.89 ms	Billed Duration: 200 ms	Memory Size: 128 MB	Max Memory Used: 96 MB	

I would have expected a thrown exception to cause the Lambda function to fail.

[gunnargrosch]

Not throwing the exception is an oversight from my end in the rush to release on Christmas eve. It should of course do that. :)

So with that and your PR for catchException flag in mind, do you see any scenario when we don't want to throw the exception?

[gunnargrosch]

Merged part of the code to fix the issue with not throwing the exception and published a new version of the package. The question if we want catchException flag is still open.

[jpbarto]

@gunnargrosch my thinking was that there may be merit to wanting the Lambda function to exit with an error without necessarily reporting the error to Lambda. Putting potentially dangerous code inside a try / catch is very common in my experience - so I think it would be valuable to have as a feature.

[gunnargrosch]

@jpbarto Sounds good to me! To keep this as a minor update I would like the setting in the parameter to be optional. Would mean that users don't have change their parameters to use the new version. I guess that means a simple if statement by the newly added throw ex.