initial commit of MongoDB backend

.github/workflows/mongodb_settings.py

@@ -0,0 +1,14 @@
+DATABASES = {
+    "default": {
+        "ENGINE": "django_mongodb",
+        "NAME": "djangotests",
+    },
+    "other": {
+        "ENGINE": "django_mongodb",
+        "NAME": "djangotests-other",
+    },
+}
+DEFAULT_AUTO_FIELD = "django_mongodb.fields.MongoAutoField"
+PASSWORD_HASHERS = ("django.contrib.auth.hashers.MD5PasswordHasher",)
+SECRET_KEY = "django_tests_secret_key"
+USE_TZ = False

.github/workflows/test-python.yml

@@ -2,6 +2,8 @@ name: Python Tests
 
 on:
   push:
+    branches:
+    - main
   pull_request:
   workflow_dispatch:
 
@@ -21,7 +23,7 @@ jobs:
       - uses: actions/checkout@v4
       - uses: actions/setup-python@v5
         with:
-          python-version: 3.8
+          python-version: '3.10'
           cache: 'pip'
           cache-dependency-path: 'pyproject.toml'
       - name: Install Python dependencies
@@ -32,33 +34,50 @@ jobs:
           pre-commit run --hook-stage=manual --all-files
 
   build:
-    # supercharge/mongodb-github-action requires containers so we don't test other platforms
-    runs-on: ${{ matrix.os }}
-    strategy:
-      matrix:
-        os: [ubuntu-20.04]
-        python-version: ["3.8", "3.11", "pypy-3.9"]
-      fail-fast: false
-    name: CPython ${{ matrix.python-version }}-${{ matrix.os }}
+    name: Django Test Suite
+    runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
-      - name: Setup Python
-        uses: actions/setup-python@v5
+      - name: Checkout django-mongodb
+        uses: actions/checkout@v4
+      - name: install the django-mongodb backend
+        run: |
+          pip3 install --upgrade pip
+          pip3 install -e .
+      - name: Checkout Django
+        uses: actions/checkout@v4
         with:
-          python-version: ${{ matrix.python-version }}
-          cache: 'pip'
-          cache-dependency-path: 'pyproject.toml'
-      - name: Install dependencies
+          repository: 'mongodb-forks/django'
+          ref: 'mongodb-5.0.x'
+          path: 'django_repo'
+      - name: Install system packages for Django's Python test dependencies
         run: |
-          pip install -U pip
-          pip install -e ".[test]"
+          sudo apt-get update
+          sudo apt-get install libmemcached-dev
+      - name: Install Django and its Python test dependencies
+        run: |
+          cd django_repo/tests/
+          pip3 install -e ..
+          pip3 install -r requirements/py3.txt
+      - name: Copy the test settings file
+        run: cp .github/workflows/mongodb_settings.py django_repo/tests/
       - name: Start MongoDB
         uses: supercharge/mongodb-github-action@1.10.0
         with:
           mongodb-version: 4.4
       - name: Run tests
-        run: |
-          pytest
+        run: >
+          python3 django_repo/tests/runtests.py --settings mongodb_settings -v 2
+          basic
+          empty
+          defer
+          defer_regress
+          from_db_value
+          lookup.tests.LookupTests.test_escaping
+          lookup.tests.LookupTests.test_isnull_textfield
+          lookup.tests.LookupQueryingTests.test_isnull_lookup_in_filter
+          model_fields
+          or_lookups
+          sessions_tests
 
   docs:
     name: Docs Checks
@@ -69,8 +88,7 @@ jobs:
         with:
           cache: 'pip'
           cache-dependency-path: 'pyproject.toml'
-          # Build docs on lowest supported Python for furo
-          python-version: '3.8'
+          python-version: '3.10'
       - name: Install dependencies
         run: |
           pip install -U pip

.pre-commit-config.yaml

@@ -72,17 +72,8 @@ repos:
       args: ["--schemafile", "https://json.schemastore.org/github-workflow"]
       stages: [manual]
 
-- repo: https://github.com/ariebovenberg/slotscheck
-  rev: v0.17.0
-  hooks:
-  - id: slotscheck
-    files: \.py$
-    exclude: "^(test|docs)/"
-    stages: [manual]
-    args: ["--no-strict-imports"]
-
 - repo: https://github.com/codespell-project/codespell
   rev: "v2.2.6"
   hooks:
   - id: codespell
-    args: ["-L", ""]
+    args: ["-L", "nin"]

README.md

@@ -1,39 +1,65 @@
 # MongoDB backend for Django
 
-This library is in the early stages of development, and so it's possible the API may change in the future - we definitely want to continue expanding it. We welcome your feedback as we continue to explore and build this tool.
+This backend is in the pre-alpha stage of development. Backwards incompatible
+changes may be made without notice. We welcome your feedback as we continue to
+explore and build.
 
 ## Install and usage
 
 Use the version of `django-mongodb` that corresponds to your version of
 Django. For example, to get the latest compatible release for Django 5.0.x:
 
-`pip install django-mongodb==0.1.*`
+`pip install django-mongodb==5.0.*`
 
 The minor release number of Django doesn't correspond to the minor release
 number of django-mongodb. Use the latest minor release of each.
 
+While django-mongodb only has pre-releases (alphas or betas), you'll see an
+error with a list of the available versions. In that case, include `--pre` to
+allow `pip` to install the latest pre-release.
+
+For example, if django-mongodb 5.0 alpha 1 is the latest available version
+of the 5.0 release series:
+
+```
+$ pip install django-mongodb==5.0.*
+ERROR: Could not find a version that satisfies the requirement
+django-mongodb==5.0.* (from versions: ..., 5.0a1)
+
+$ pip install --pre django-mongodb==5.0.*
+...
+Successfully installed ... django-mongodb-5.0a1 ...
+```
+
 Configure the Django `DATABASES` setting similar to this:
 
 ```python
 DATABASES = {
     "default": {
         "ENGINE": "django_mongodb",
-        "NAME": "MY_DATABASE",
-        "SCHEMA": "MY_SCHEMA",
-        "WAREHOUSE": "MY_WAREHOUSE",
+        "NAME": "my_database",
         "USER": "my_user",
         "PASSWORD": "my_password",
-        "ACCOUNT": "my_account",
     },
 }
 ```
 
 ## Known issues and limitations
 
-TODO
+- The following `QuerySet` methods aren't supported:
+  - `aggregate()`
+  - `distinct()`
+  - `extra()`
+  - `select_related()`
 
-## Troubleshooting
+- Queries with joins aren't supported.
 
-### Debug logging
+## Troubleshooting
 
 TODO
+
+## Credits
+
+This project began by borrowing code from Django non-rel's
+[MongoDB Engine](https://github.com/django-nonrel/mongodb-engine),
+abandoned since 2015 and Django 1.6 (2-clause BSD license).

django_mongodb/__init__.py

@@ -0,0 +1,7 @@
+__version__ = "5.0a0"
+
+# Check Django compatibility before other imports which may fail if the
+# wrong version of Django is installed.
+from .utils import check_django_compatability
+
+check_django_compatability()

django_mongodb/base.py

@@ -0,0 +1,121 @@
+from django.core.exceptions import ImproperlyConfigured
+from django.db.backends.base.base import BaseDatabaseWrapper
+from django.db.backends.signals import connection_created
+from pymongo.collection import Collection
+from pymongo.mongo_client import MongoClient
+
+from . import dbapi as Database
+from .client import DatabaseClient
+from .creation import DatabaseCreation
+from .features import DatabaseFeatures
+from .introspection import DatabaseIntrospection
+from .operations import DatabaseOperations
+from .schema import DatabaseSchemaEditor
+
+
+class Cursor:
+    """A "nodb" cursor that does nothing except work on a context manager."""
+
+    def __enter__(self):
+        pass
+
+    def __exit__(self, exception_type, exception_value, exception_traceback):
+        pass
+
+
+class DatabaseWrapper(BaseDatabaseWrapper):
+    data_types = {
+        "AutoField": "int",
+        "BigAutoField": "long",
+        "BinaryField": "binData",
+        "BooleanField": "bool",
+        "CharField": "string",
+        "DateField": "date",
+        "DateTimeField": "date",
+        "DecimalField": "decimal",
+        "DurationField": "long",
+        "FileField": "string",
+        "FilePathField": "string",
+        "FloatField": "double",
+        "IntegerField": "int",
+        "BigIntegerField": "long",
+        "GenericIPAddressField": "string",
+        "NullBooleanField": "bool",
+        "OneToOneField": "int",
+        "PositiveIntegerField": "long",
+        "PositiveSmallIntegerField": "int",
+        "SlugField": "string",
+        "SmallIntegerField": "int",
+        "TextField": "string",
+        "TimeField": "date",
+        "UUIDField": "string",
+    }
+
+    vendor = "mongodb"
+    Database = Database
+    SchemaEditorClass = DatabaseSchemaEditor
+    client_class = DatabaseClient
+    creation_class = DatabaseCreation
+    features_class = DatabaseFeatures
+    introspection_class = DatabaseIntrospection
+    ops_class = DatabaseOperations
+
+    def __init__(self, *args, **kwargs):
+        super().__init__(*args, **kwargs)
+        self.connected = False
+        del self.connection
+
+    def get_collection(self, name, **kwargs):
+        return Collection(self.database, name, **kwargs)
+
+    def __getattr__(self, attr):
+        """
+        Connect to the database the first time `connection` or `database` are
+        accessed.
+        """
+        if attr in ["connection", "database"]:
+            assert not self.connected
+            self._connect()
+            return getattr(self, attr)
+        raise AttributeError(attr)
+
+    def _connect(self):
+        settings_dict = self.settings_dict
+
+        options = settings_dict["OPTIONS"]
+        # TODO: review and document OPERATIONS: https://github.com/mongodb-labs/django-mongodb/issues/6
+        self.operation_flags = options.pop("OPERATIONS", {})
+        if not any(k in ["save", "delete", "update"] for k in self.operation_flags):
+            # Flags apply to all operations.
+            flags = self.operation_flags
+            self.operation_flags = {"save": flags, "delete": flags, "update": flags}
+
+        self.connection = MongoClient(
+            host=settings_dict["HOST"] or None, port=int(settings_dict["PORT"] or 27017), **options
+        )
+        db_name = settings_dict["NAME"]
+        if db_name:
+            self.database = self.connection[db_name]
+
+        user = settings_dict["USER"]
+        password = settings_dict["PASSWORD"]
+        if user and password and not self.database.authenticate(user, password):
+            raise ImproperlyConfigured("Invalid username or password.")
+
+        self.connected = True
+        connection_created.send(sender=self.__class__, connection=self)
+
+    def _commit(self):
+        pass
+
+    def _rollback(self):
+        pass
+
+    def close(self):
+        if self.connected:
+            del self.connection
+            del self.database
+            self.connected = False
+
+    def cursor(self):
+        return Cursor()

django_mongodb/client.py

@@ -0,0 +1,21 @@
+import signal
+
+from django.db.backends.base.client import BaseDatabaseClient
+
+
+class DatabaseClient(BaseDatabaseClient):
+    executable_name = "mongo"
+
+    @classmethod
+    def settings_to_cmd_args_env(cls, settings_dict, parameters):
+        raise NotImplementedError
+
+    def runshell(self, parameters):
+        sigint_handler = signal.getsignal(signal.SIGINT)
+        try:
+            # Allow SIGINT to pass to mongo to abort queries.
+            signal.signal(signal.SIGINT, signal.SIG_IGN)
+            super().runshell(parameters)
+        finally:
+            # Restore the original SIGINT handler.
+            signal.signal(signal.SIGINT, sigint_handler)