Add explicit base class for ActiveJob jobs

[jvanbaarsen]

• Jobs generated should inherent from ApplicationJob
• ApplicationJob inherents from ActiveJob::Base

Fixes #16976

/cc @tamird @rafaelfranca

[georgeclaghorn]

Any reason not to create ApplicationJob when a new app is first created, like ApplicationController?

[jvanbaarsen]

@georgeclaghorn Since not everyone might be using ActiveJob. But maybe it would be better to have it there right from the get go. @rafaelfranca @tamird what do you think?

[egilburg]

I remember at some point there was Rails PR for ApplicationModel that all models inherited from (rather than ActiveRecord::Base, and then it didn't make it for some reason. :-(

[cristianbica]

app/jobs/application_job.rb should be from the beginning just like application_controller.rb. Also it would be nice if we show a log warning for people that inherit from ActiveJob::Base to switch to ApplicationJob.

[jvanbaarsen]

Ok! I'll add it to the app generator :-) and I'll see if I can figure out the warning :)

[jvanbaarsen]

@cristianbica Im looking into the warnings, but not really sure how to tackle this. And besides, I checked with controllers. Its not something we do there (You can use a controller without inhereting from ApplicationController, without a warning). What do you think?

[rebyn]

Im looking into the warnings, but not really sure how to tackle this.

Some really wild thoughts:

• warning when people upgrade their Rails gem
• warning when people run their jobs (and check for the class?)

[jvanbaarsen]

@cristianbica What do you think?

[cristianbica]

Yes talked with the rails team and the warning is not something we want. We don't want to prohibit subclassing ActiveJob::Base but we want to encourage people to don't mangle with ActiveJob::Base directly. So there's no need for a warning. We need a changelog and some suggestions in the rails 5 upgrade guide.

[jvanbaarsen]

@cristianbica Ok thanks! I'll fix those later tonight.

[jvanbaarsen]

@cristianbica Somehow I had to change this line otherwise the tests did not pass. Do you have any idea why that is? It is because I added the application_job.rb file?

[cristianbica]

probably yes

[jvanbaarsen]

@cristianbica What can I do to get this merged?

[cristianbica]

Please squash your commits. Otherwise seems good to me.

@rafaelfranca

[jvanbaarsen]

@cristianbica Squashed commits. Waiting for build to be green

[jvanbaarsen]

@cristianbica Test are passing, and the commits are squashed. Anything left for me to do?

[cristianbica]

nice. thanks @jvanbaarsen

[chancancode]

For the future, this should go on top of the file :)

[jvanbaarsen]

Ah ok :)