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I assume Dan really means a nested directory structure, like so: django_project/top_level_app/second_level_app/ in top_level_app you then could do from secon

I assume Dan really means a nested directory structure, like so: django_project/top_level_app/second_level_app/ in top_level_app you then could do from second_level_app.models import model1 or from a different top level app: from other_top_level_app.second_level_app.mixins import a_mixin

danpalmer 8y ago
Yep, exactly this. For example: project/orders/orders_shipping/orders_ups Unfortunately app names have a global namespace within Django's model registry, so we often have to prefix nested apps. The place where this really works nicely is user facing features and internal editing interfaces, or in features where we have N of a feature that are all similar. For the former, we might have an app such as "blog", and then a nested app within that called "blog_editor". This way we can separate blog models, business logic and user-facing behaviour, from CRUD interfaces designed for internal users. In the latter, if we have 3 shipping providers, we might have an app "shipping" with the core shipping models, with nested apps for "ups", "royal_mail", "dpd", etc, each of which might have the necessary models needed to manage uploading to their APIs, business logic, etc. There may be a common-ish interface exposed by these apps. This structure is probably the thing I like most about Django over, say, Rails. It's not necessary for all Django projects, but I think it's pretty nice.
- kumarvvr 8y ago
  Within a single app, could this not be done mith multiple model files, and multiple services files. I usually organize my apps by having a services layer between models and views, such that the view functions have little to no knowledge about the underlying models. This, in place of nested apps, I have "upsmodels.py" and "upsservice.py" and the view functions handles routing logic.
  - danpalmer 8y ago
    That would indeed work, however given that one app can have ~20 nested apps at the first level, this might become tricky to manage. There's a lot to be said to having a directory with ~5 files in it that is all you need to keep in your head for a feature.

danpalmer 8y ago

Yep, exactly this. For example: project/orders/orders_shipping/orders_ups Unfortunately app names have a global namespace within Django's model registry, so we often have to prefix nested apps. The place where this really works nicely is user facing features and internal editing interfaces, or in features where we have N of a feature that are all similar. For the former, we might have an app such as "blog", and then a nested app within that called "blog_editor". This way we can separate blog models, business logic and user-facing behaviour, from CRUD interfaces designed for internal users. In the latter, if we have 3 shipping providers, we might have an app "shipping" with the core shipping models, with nested apps for "ups", "royal_mail", "dpd", etc, each of which might have the necessary models needed to manage uploading to their APIs, business logic, etc. There may be a common-ish interface exposed by these apps. This structure is probably the thing I like most about Django over, say, Rails. It's not necessary for all Django projects, but I think it's pretty nice.

kumarvvr 8y ago
Within a single app, could this not be done mith multiple model files, and multiple services files. I usually organize my apps by having a services layer between models and views, such that the view functions have little to no knowledge about the underlying models. This, in place of nested apps, I have "upsmodels.py" and "upsservice.py" and the view functions handles routing logic.
- danpalmer 8y ago
  That would indeed work, however given that one app can have ~20 nested apps at the first level, this might become tricky to manage. There's a lot to be said to having a directory with ~5 files in it that is all you need to keep in your head for a feature.