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hynekcer / django-salesforce-stubs is a clone of django-stubs with the added "salesforce" branch that is a default branch here. It is used for static type check with an alternate database backend django-salesforce.

The differences of the "salesforce" branch are:

  1. It annotates also some internal parts of django.db.
  2. It adds a few custom methods specific for django-salesforce to models/manager.pyi and models/query.pyi These methods are implemented in a descendant module in "django-salesforce" package, but the smart features of django-stubs require that typing of generic classes must be declared in django-stubs, not in descendant classes. These added methods can be found in the source after a line # for Salesforce.
  3. The version number is with an added fourth digit that is an incremental version important for dependency of django-salesforce annotations on django-salesforce-stubs. It will be never on PyPi. The actual install link depends on django-salesforce version and can be found there in "tox.ini" on a line similar to git+https://github.com/hynekcer/django-salesforce-stubs.git@v1.5.0.1#django-stubs .

An additional not yet implemented idea is to annotate a general database backend to which all backends can be ckecked that are compatible with it and that is sufficient for the rest of django.db.


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Typesafe Django Framework

Build Status Checked with mypy Gitter

This package contains type stubs and a custom mypy plugin to provide more precise static types and type inference for Django framework. Django uses some Python "magic" that makes having precise types for some code patterns problematic. This is why we need this project. The final goal is to be able to get precise types for most common patterns.

Contributing to this fork:

  • Issues are accepted if something that worked in django-stubs would not work in django-salesforce-stubs.
  • Issues that are the same in in the original django-stubs should be directed there.
  • Issues related to Salesforce (all other issues) are accepted only with a pull request that fixes it. (no capacity for them probably)

Installation

pip install django-stubs

See Configuration section to get started.

Configuration

To make mypy happy, you will need to add:

[mypy]
plugins =
    mypy_django_plugin.main

[mypy.plugins.django-stubs]
django_settings_module = "myproject.settings"

in your mypy.ini or setup.cfg file.

Two things happeining here:

  1. We need to explicitly list our plugin to be loaded by mypy
  2. Our plugin also requires django settings module (what you put into DJANGO_SETTINGS_MODULE variable) to be specified

This fully working typed boilerplate can serve you as an example.

Version compatibility

We rely on different django and mypy versions:

django-stubs mypy version django version python version
1.5.0 0.770 ? ^3.6
1.4.0 0.760 ? ^3.6
1.3.0 0.750 2.2.x ^3.6
1.2.0 0.730 2.2.x ^3.6
1.1.0 0.720 2.2.x ^3.6
0.12.x old semantic analyzer (<0.711), dmypy support 2.1.x ^3.6

FAQ

Is this an official Django project?

No, it is not. We are indendepent from Django at the moment. There's a proposal to merge our project into the Django itself. You show your support by linking the PR.

Is it safe to use this in production?

Yes, it is! This project does not affect your runtime at all. It only affects mypy type checking process.

But, it does not make any sense to use this project without mypy.

mypy crashes when I run it with this plugin installed

Current implementation uses Django runtime to extract models information, so it will crash, if your installed apps or models.py is not correct. For this same reason, you cannot use reveal_type inside global scope of any Python file that will be executed for django.setup().

In other words, if your manage.py runserver crashes, mypy will crash too. You can also run mypy with --tb option to get extra information about the error.

I cannot use QuerySet or Manager with type annotations

You can get a TypeError: 'type' object is not subscriptable when you will try to use QuerySet[MyModel] or Manager[MyModel].

This happens because Django classes do not support __class_getitem__ magic method.

You can use strings instead: 'QuerySet[MyModel]' and 'Manager[MyModel]', this way it will work as a type for mypy and as a regular str in runtime.

Currently we are working on providing __class_getitem__ to the classes where we need them.

How can I use HttpRequest with custom user model?

You can subclass standard request like so:

from django.http import HttpRequest
from my_user_app.models import MyUser

class MyRequest(HttpRequest):
    user: MyUser

And then use MyRequest instead of standard HttpRequest inside your project.

Related projects

To get help

We have Gitter here: https://gitter.im/mypy-django/Lobby

If you think you have more generic typing issue, please refer to https://github.com/python/mypy and their Gitter.