Yet another Pydantic 2 support (#832)

* Add support for Pydantic v2 settings

* Configure pipeline to run tests against different pydantic versions

* Update Pydantic docs and examples for v2

* Fix compatibility with httpx v0.27.0

Author: ZipFile

.github/workflows/tests-and-linters.yml

@@ -36,6 +36,17 @@ jobs:
         env:
           TOXENV: ${{ matrix.python-version }}
 
+  test-different-pydantic-versions:
+    name: Run tests with different pydantic versions
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+      - uses: actions/setup-python@v4
+        with:
+          python-version: "3.12"
+      - run: pip install tox
+      - run: tox -e pydantic-v1,pydantic-v2
+
   test-coverage:
     name: Run tests with coverage
     runs-on: ubuntu-latest

docs/providers/configuration.rst

@@ -183,22 +183,22 @@ See also: :ref:`configuration-envs-interpolation`.
 Loading from a Pydantic settings
 --------------------------------
 
-``Configuration`` provider can load configuration from a ``pydantic`` settings object using the
+``Configuration`` provider can load configuration from a ``pydantic_settings.BaseSettings`` object using the
 :py:meth:`Configuration.from_pydantic` method:
 
 .. literalinclude:: ../../examples/providers/configuration/configuration_pydantic.py
    :language: python
    :lines: 3-
-   :emphasize-lines: 31
+   :emphasize-lines: 32
 
-To get the data from pydantic settings ``Configuration`` provider calls ``Settings.dict()`` method.
+To get the data from pydantic settings ``Configuration`` provider calls its ``model_dump()`` method.
 If you need to pass an argument to this call, use ``.from_pydantic()`` keyword arguments.
 
 .. code-block:: python
 
    container.config.from_pydantic(Settings(), exclude={"optional"})
 
-Alternatively, you can provide a ``pydantic`` settings object over the configuration provider argument. In that case,
+Alternatively, you can provide a ``pydantic_settings.BaseSettings`` object over the configuration provider argument. In that case,
 the container will call ``config.from_pydantic()`` automatically:
 
 .. code-block:: python
@@ -215,18 +215,23 @@ the container will call ``config.from_pydantic()`` automatically:
 
 .. note::
 
-   ``Dependency Injector`` doesn't install ``pydantic`` by default.
+   ``Dependency Injector`` doesn't install ``pydantic-settings`` by default.
 
    You can install the ``Dependency Injector`` with an extra dependency::
 
-      pip install dependency-injector[pydantic]
+      pip install dependency-injector[pydantic2]
 
-   or install ``pydantic`` directly::
+   or install ``pydantic-settings`` directly::
 
-      pip install pydantic
+      pip install pydantic-settings
 
    *Don't forget to mirror the changes in the requirements file.*
 
+.. note::
+
+   For backward-compatibility, Pydantic v1 is still supported.
+   Passing ``pydantic.BaseSettings`` instances will work just as fine as ``pydantic_settings.BaseSettings``.
+
 Loading from a dictionary
 -------------------------
 

examples/miniapps/fastapi-redis/fastapiredis/tests.py

@@ -3,15 +3,18 @@
 from unittest import mock
 
 import pytest
-from httpx import AsyncClient
+from httpx import ASGITransport, AsyncClient
 
 from .application import app, container
 from .services import Service
 
 
 @pytest.fixture
 def client(event_loop):
-    client = AsyncClient(app=app, base_url="http://test")
+    client = AsyncClient(
+        transport=ASGITransport(app=app),
+        base_url="http://test",
+    )
     yield client
     event_loop.run_until_complete(client.aclose())
 

examples/miniapps/fastapi-simple/tests.py

@@ -1,14 +1,17 @@
 from unittest import mock
 
 import pytest
-from httpx import AsyncClient
+from httpx import ASGITransport, AsyncClient
 
 from fastapi_di_example import app, container, Service
 
 
 @pytest.fixture
 async def client(event_loop):
-    async with AsyncClient(app=app, base_url="http://test") as client:
+    async with AsyncClient(
+        transport=ASGITransport(app=app),
+        base_url="http://test",
+    ) as client:
         yield client
 
 

examples/miniapps/fastapi/giphynavigator/tests.py

@@ -3,15 +3,18 @@
 from unittest import mock
 
 import pytest
-from httpx import AsyncClient
+from httpx import ASGITransport, AsyncClient
 
 from giphynavigator.application import app
 from giphynavigator.giphy import GiphyClient
 
 
 @pytest.fixture
 async def client():
-    async with AsyncClient(app=app, base_url="http://test") as client:
+    async with AsyncClient(
+        transport=ASGITransport(app=app),
+        base_url="http://test",
+    ) as client:
         yield client
 
 

examples/providers/configuration/configuration_pydantic.py

@@ -3,23 +3,24 @@
 import os
 
 from dependency_injector import containers, providers
-from pydantic import BaseSettings, Field
+from pydantic_settings import BaseSettings, SettingsConfigDict
 
 # Emulate environment variables
 os.environ["AWS_ACCESS_KEY_ID"] = "KEY"
 os.environ["AWS_SECRET_ACCESS_KEY"] = "SECRET"
 
 
 class AwsSettings(BaseSettings):
+    model_config = SettingsConfigDict(env_prefix="aws_")
 
-    access_key_id: str = Field(env="aws_access_key_id")
-    secret_access_key: str = Field(env="aws_secret_access_key")
+    access_key_id: str
+    secret_access_key: str
 
 
 class Settings(BaseSettings):
 
     aws: AwsSettings = AwsSettings()
-    optional: str = Field(default="default_value")
+    optional: str = "default_value"
 
 
 class Container(containers.DeclarativeContainer):

examples/providers/configuration/configuration_pydantic_init.py

@@ -3,23 +3,24 @@
 import os
 
 from dependency_injector import containers, providers
-from pydantic import BaseSettings, Field
+from pydantic_settings import BaseSettings, SettingsConfigDict
 
 # Emulate environment variables
 os.environ["AWS_ACCESS_KEY_ID"] = "KEY"
 os.environ["AWS_SECRET_ACCESS_KEY"] = "SECRET"
 
 
 class AwsSettings(BaseSettings):
+    model_config = SettingsConfigDict(env_prefix="aws_")
 
-    access_key_id: str = Field(env="aws_access_key_id")
-    secret_access_key: str = Field(env="aws_secret_access_key")
+    access_key_id: str
+    secret_access_key: str
 
 
 class Settings(BaseSettings):
 
     aws: AwsSettings = AwsSettings()
-    optional: str = Field(default="default_value")
+    optional: str = "default_value"
 
 
 class Container(containers.DeclarativeContainer):

pyproject.toml

@@ -58,6 +58,7 @@ dependencies = ["six"]
 [project.optional-dependencies]
 yaml = ["pyyaml"]
 pydantic = ["pydantic"]
+pydantic2 = ["pydantic-settings"]
 flask = ["flask"]
 aiohttp = ["aiohttp"]
 

src/dependency_injector/providers.pyx

@@ -48,10 +48,25 @@ try:
 except ImportError:
     yaml = None
 
+has_pydantic_settings = True
+cdef bint pydantic_v1 = False
+cdef str pydantic_module = "pydantic_settings"
+cdef str pydantic_extra = "pydantic2"
+
 try:
-    import pydantic
+    from pydantic_settings import BaseSettings as PydanticSettings
 except ImportError:
-    pydantic = None
+    try:
+        # pydantic-settings requires pydantic v2,
+        # so it is safe to assume that we're dealing with v1:
+        from pydantic import BaseSettings as PydanticSettings
+        pydantic_v1 = True
+        pydantic_module = "pydantic"
+        pydantic_extra = "pydantic"
+    except ImportError:
+        # if it is present, ofc
+        has_pydantic_settings = False
+
 
 from .errors import (
     Error,
@@ -149,6 +164,31 @@ cdef int ASYNC_MODE_DISABLED = 2
 cdef set __iscoroutine_typecache = set()
 cdef tuple __COROUTINE_TYPES = asyncio.coroutines._COROUTINE_TYPES if asyncio else tuple()
 
+cdef dict pydantic_settings_to_dict(settings, dict kwargs):
+    if not has_pydantic_settings:
+        raise Error(
+            f"Unable to load pydantic configuration - {pydantic_module} is not installed. "
+            "Install pydantic or install Dependency Injector with pydantic extras: "
+            f"\"pip install dependency-injector[{pydantic_extra}]\""
+        )
+
+    if isinstance(settings, CLASS_TYPES) and issubclass(settings, PydanticSettings):
+        raise Error(
+            "Got settings class, but expect instance: "
+            "instead \"{0}\" use \"{0}()\"".format(settings.__name__)
+        )
+
+    if not isinstance(settings, PydanticSettings):
+        raise Error(
+            f"Unable to recognize settings instance, expect \"{pydantic_module}.BaseSettings\", "
+            f"got {settings} instead"
+        )
+
+    if pydantic_v1:
+        return settings.dict(**kwargs)
+
+    return settings.model_dump(mode="python", **kwargs)
+
 
 cdef class Provider(object):
     """Base provider class.
@@ -1786,36 +1826,20 @@ cdef class ConfigurationOption(Provider):
         Loaded configuration is merged recursively over existing configuration.
 
         :param settings: Pydantic settings instances.
-        :type settings: :py:class:`pydantic.BaseSettings`
+        :type settings: :py:class:`pydantic.BaseSettings` (pydantic v1) or
+            :py:class:`pydantic_settings.BaseSettings` (pydantic v2 and onwards)
 
         :param required: When required is True, raise an exception if settings dict is empty.
         :type required: bool
 
-        :param kwargs: Keyword arguments forwarded to ``pydantic.BaseSettings.dict()`` call.
+        :param kwargs: Keyword arguments forwarded to ``pydantic.BaseSettings.dict()`` or
+            ``pydantic_settings.BaseSettings.model_dump()`` call (based on pydantic version).
         :type kwargs: Dict[Any, Any]
 
         :rtype: None
         """
-        if pydantic is None:
-            raise Error(
-                "Unable to load pydantic configuration - pydantic is not installed. "
-                "Install pydantic or install Dependency Injector with pydantic extras: "
-                "\"pip install dependency-injector[pydantic]\""
-            )
 
-        if isinstance(settings, CLASS_TYPES) and issubclass(settings, pydantic.BaseSettings):
-            raise Error(
-                "Got settings class, but expect instance: "
-                "instead \"{0}\" use \"{0}()\"".format(settings.__name__)
-            )
-
-        if not isinstance(settings, pydantic.BaseSettings):
-            raise Error(
-                "Unable to recognize settings instance, expect \"pydantic.BaseSettings\", "
-                "got {0} instead".format(settings)
-            )
-
-        self.from_dict(settings.dict(**kwargs), required=required)
+        self.from_dict(pydantic_settings_to_dict(settings, kwargs), required=required)
 
     def from_dict(self, options, required=UNDEFINED):
         """Load configuration from the dictionary.
@@ -2355,7 +2379,8 @@ cdef class Configuration(Object):
         Loaded configuration is merged recursively over existing configuration.
 
         :param settings: Pydantic settings instances.
-        :type settings: :py:class:`pydantic.BaseSettings`
+        :type settings: :py:class:`pydantic.BaseSettings` (pydantic v1) or
+            :py:class:`pydantic_settings.BaseSettings` (pydantic v2 and onwards)
 
         :param required: When required is True, raise an exception if settings dict is empty.
         :type required: bool
@@ -2365,26 +2390,8 @@ cdef class Configuration(Object):
 
         :rtype: None
         """
-        if pydantic is None:
-            raise Error(
-                "Unable to load pydantic configuration - pydantic is not installed. "
-                "Install pydantic or install Dependency Injector with pydantic extras: "
-                "\"pip install dependency-injector[pydantic]\""
-            )
-
-        if isinstance(settings, CLASS_TYPES) and issubclass(settings, pydantic.BaseSettings):
-            raise Error(
-                "Got settings class, but expect instance: "
-                "instead \"{0}\" use \"{0}()\"".format(settings.__name__)
-            )
-
-        if not isinstance(settings, pydantic.BaseSettings):
-            raise Error(
-                "Unable to recognize settings instance, expect \"pydantic.BaseSettings\", "
-                "got {0} instead".format(settings)
-            )
 
-        self.from_dict(settings.dict(**kwargs), required=required)
+        self.from_dict(pydantic_settings_to_dict(settings, kwargs), required=required)
 
     def from_dict(self, options, required=UNDEFINED):
         """Load configuration from the dictionary.

tests/.configs/pytest.ini

@@ -2,6 +2,8 @@
 testpaths = tests/unit/
 python_files = test_*_py3*.py
 asyncio_mode = auto
+markers =
+    pydantic: Tests with Pydantic as a dependency
 filterwarnings =
     ignore:Module \"dependency_injector.ext.aiohttp\" is deprecated since version 4\.0\.0:DeprecationWarning
     ignore:Module \"dependency_injector.ext.flask\" is deprecated since version 4\.0\.0:DeprecationWarning