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0 pointshbrn3y ago0 comments

The short answer is yes.

The long answer is if two entities are updating each other you might benefit from shifting all update responsibilities to one of them. Or even to a third entity that knows about both and keeps those two isolated from each other.

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cjohnson3183y ago

Woof. Thank you so much. I like the idea of a third party, like a mediator.

Would that mediator be another app? Or should it be some module sitting in the project directory? (I'm not even sure Django would import something like that.)

hbrnOP3y ago

> Would that mediator be another app?

Yes!

It is an app that might not even have any model classes. But it will contain business logic. And it will probably speak domain language, which is great.

If you're lucky, those two other apps will become pluggable. You will probably never replace them, but separation of concerns is always nice.

The downside of course is that you will have 3 apps instead of 1. That's the balance you have to maintain.

cjohnson3183y ago

So, the way I understand it, job/services.py and load/services.py depend on mediator/mediator.py which depends on job/models.py and load/models.py, instead of job/services.py ultimately using load/services.py, and vice versa.

Thanks so much!

hbrnOP3y ago

This is good enough to break circular dependencies between individual modules, but keep in mind that circular dependencies between the apps remain (e.g. job depends on mediator, mediator depends on job).

I usually prefer to resolve those too. If job is small enough, all the orchestration of jobs should happen through mediator (same for load). If it's not plausible, then job can emit signals which mediator subscribes to.

A good place to start is to give a more descriptive name to the mediator. Sure, it mediates between the two, but it probably does that to implement some business process. Can you name it after that process?

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cjohnson3183y ago

Woof. Thank you so much. I like the idea of a third party, like a mediator.

Would that mediator be another app? Or should it be some module sitting in the project directory? (I'm not even sure Django would import something like that.)

hbrnOP3y ago

> Would that mediator be another app?

Yes!

It is an app that might not even have any model classes. But it will contain business logic. And it will probably speak domain language, which is great.

If you're lucky, those two other apps will become pluggable. You will probably never replace them, but separation of concerns is always nice.

The downside of course is that you will have 3 apps instead of 1. That's the balance you have to maintain.

cjohnson3183y ago

Thanks so much!

hbrnOP3y ago

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j / k navigate · click thread line to collapse