Feature: cancel and/or dequeue jobs

[nicooga]

I need a job to run once X time after the last occurrence of an repeating event.

For example, In UI and game development I've seen this behavior when a user hits a button a something happens only N seconds after the last hit. Any other hit before N seconds cancels the old timer and sets a new one.

To put you in context, my site is an e-commerce and I need to implement a feature where 30min or so after the last time the user seen a page (a pageview in analytics terms), a marketing email is sent to they.

The way I solved this with Ruby and Sidekiq was running this algorithm each time a pageview event for a n user is created:

if (is there an associated job ID for this user?) {
  cancel that job
}

schedule a job to send the email 30 minutes from now
associate the ID for the job I've just created with this user

TL;DR: I need a way to dequeue jobs.

I see there is a dequeue function in Exq.Redis.JobQueue. There is no interface in Exq.Enqueuer.EnqueueApi to use it though. Is there a particular reason not to expose this feature?