Project Structure

Preamble

In django universe the official propagated way to strucure a project is to use apps (a carryover from Django vernacular). But there are many discussions out there about the question when we have to make an app?.

To understand our project structure, it is important to specify some terms first, so that everyone which likes to understand the code uses the same vocabulary.

What is an app?

In our opinion an app in a django project shall be a django specific python package, which is independend from other apps. The most common reason to start an app is to create reusable code.

A Django View is Not a Controller

A default app structure in django is splitted in some basic modules:

  • app_folder * models.py * urls.py * views.py * ...

Like discussed in article the module views.py is not the controller module. Citation from the article: “The view in Django is most often described as being equivalent to the controller in MVC, but it’s not—it’s still the view.”

Where to put app logic code then?

Follow the question from the article:

Does the function/class return a response?

    * YES — it’s a view. Put it in the views module (views.py).
    * NO — it’s not a view, it’s app logic. Put it somewhere else (somewhere_else.py).

Package Overview

  • accounts: generic implementation of access control list management for django guaridan permissions.

  • extras: global project wide used django specific code.

  • MrMap: django project root for mrmap project.

  • notify: handles notifications over websockets.

  • registry: spatial service registry to register and manage services like wms, wfs, csw. (monolith app)

  • tests: django and behave tests.

package/app structure

As described in Preamble on the first hirachy level we only have independend packages.

In django specific packages which are small, we use the common django way to split modules:

  • app_folder/

    • models.py

    • urls.py

    • views.py

    • ...

In larger apps we use the following structure:

  • app_folder/

    • models/

      • ogc_service.py

      • metadata.py

    • views/

      • ogc_service.py

      • metadata.py

    • ...

FAQ

Why is the registry app a monolith?

Like described in Preamble we are of the opinion that a django app shall be independend from others to reuse them. If we would split the registry app into different pieces like monitoring, security, ... we will not can use these outsourced apps stand alone. So it makes no sens to split them into different apps.