Non unique schedule redis lock key

[marcowindt]

We ran into the issue that Redis lock key for job scheduler is non-deterministic across nodes when using Jason encode, since the key is based on the MD5 hash of the serialized job. Right now the order of the keys in json object has to be the same which is not always the case, resulting in different keys for the same job.

Using a custom serializer fixes this. We now use Jason encode with ordered keys option.

Leaving a comment in case someone else runs into this in the future.

[ananthakumaran]

Thanks for reporting. If your fix is generic, we can do the same in ExqScheduler itself. I will look into this weekend

[barttenbrinke]

Ran into this too, this might be a good thing :)