Fix cancelall method in server to delete all jobs of a failed type

[databus23]

The number of jobs returned by client.jobs.failed FAILURE_TYPE defaults to the first 25 of that type. To delete all jobs of one type at once we need to explicitly specify the number of failed jobs.

[myronmarston]

Thanks, @databus23!

For perf reasons, I'm thinking that maybe this should use Qless::Client#bulk_cancel. Thoughts?

[databus23]

Sure, I didn't notice that method. I'm just wondering if there is a maximum length for arguments when calling a redis lua script? I couldn't find anything about that in the documentation. But even if it is the case we could still pass chunks of jids to bulk_cancel in a loop.

Speaking of performance, it would also be beneficial to avoid the creation of all these Job objects just to map those right back to the plain jid.
How do you feel about doing something like

jids = JSON.parse(c._failed.call [],[data['type'], 0, count])['jobs'].map { |j| j['jid']}

in the cancelall of Qless::Server ?

[wr0ngway]

+1