Re-design Flask integration

README.rst

@@ -65,20 +65,23 @@ This place is called **the container**. You use the container to manage all the
 
 *The container is like a map of your application. You always know what depends on what.*
 
-``Flask`` + ``Dependency Injector`` example:
+``Flask`` + ``Dependency Injector`` example application container:
 
 .. code-block:: python
 
     from dependency_injector import containers, providers
     from dependency_injector.ext import flask
+    from flask import Flask
     from github import Github
 
-    from . import services, views
+    from . import views, services
 
 
-    class Application(containers.DeclarativeContainer):
+    class ApplicationContainer(containers.DeclarativeContainer):
         """Application container."""
 
+        app = flask.Application(Flask, __name__)
+
         config = providers.Configuration()
 
         github_client = providers.Factory(
@@ -92,21 +95,59 @@ This place is called **the container**. You use the container to manage all the
             github_client=github_client,
         )
 
-        index_view = providers.Callable(
+        index_view = flask.View(
             views.index,
             search_service=search_service,
             default_search_term=config.search.default_term,
             default_search_limit=config.search.default_limit,
         )
 
-        app = providers.Factory(
-            flask.create_app,
-            name=__name__,
-            routes=[
-                flask.Route('/', view_provider=index_view),
-            ],
-        )
+Running such container looks like this:
 
+.. code-block:: python
+
+    from .containers import ApplicationContainer
+
+
+    def create_app():
+        """Create and return Flask application."""
+        container = ApplicationContainer()
+        container.config.from_yaml('config.yml')
+
+        app = container.app()
+        app.container = container
+
+        app.add_url_rule('/', view_func=container.index_view.as_view())
+
+        return app
+
+And testing looks like:
+
+.. code-block:: python
+
+    from unittest import mock
+
+    import pytest
+    from github import Github
+    from flask import url_for
+
+    from .application import create_app
+
+
+    @pytest.fixture
+    def app():
+        return create_app()
+
+
+    def test_index(client, app):
+        github_client_mock = mock.Mock(spec=Github)
+        # Configure mock
+
+        with app.container.github_client.override(github_client_mock):
+            response = client.get(url_for('index'))
+
+        assert response.status_code == 200
+        # Do more asserts
 
 See complete example here - `Flask + Dependency Injector Example <https://github.com/ets-labs/python-dependency-injector/tree/master/examples/miniapps/ghnav-flask>`_
 

docs/main/changelog.rst

@@ -9,6 +9,7 @@ follows `Semantic versioning`_
 
 Development version
 -------------------
+- Re-design ``Flask`` integration.
 - Make cosmetic fixes for ``Selector`` provider docs.
 
 3.20.1

examples/miniapps/ghnav-flask/README.rst

@@ -7,6 +7,13 @@ Application ``githubnavigator`` is a `Flask <https://flask.palletsprojects.com/>
 Run
 ---
 
+Create virtual environment:
+
+.. code-block:: bash
+
+   virtualenv venv
+   . venv/bin/activate
+
 Install requirements:
 
 .. code-block:: bash
@@ -17,7 +24,7 @@ To run the application do:
 
 .. code-block:: bash
 
-    export FLASK_APP=githubnavigator.entrypoint
+    export FLASK_APP=githubnavigator.application
     export FLASK_ENV=development
     flask run
 
@@ -25,7 +32,7 @@ The output should be something like:
 
 .. code-block::
 
-    * Serving Flask app "githubnavigator.entrypoint" (lazy loading)
+    * Serving Flask app "githubnavigator.application" (lazy loading)
     * Environment: development
     * Debug mode: on
     * Running on http://127.0.0.1:5000/ (Press CTRL+C to quit)
@@ -81,10 +88,10 @@ The output should be something like:
    Name                             Stmts   Miss  Cover
    ----------------------------------------------------
    githubnavigator/__init__.py          0      0   100%
-   githubnavigator/application.py      10      0   100%
-   githubnavigator/entrypoint.py        5      5     0%
-   githubnavigator/services.py         13      0   100%
-   githubnavigator/tests.py            38      0   100%
+   githubnavigator/application.py       8      0   100%
+   githubnavigator/containers.py       11      0   100%
+   githubnavigator/services.py         14      0   100%
+   githubnavigator/tests.py            33      0   100%
    githubnavigator/views.py             7      0   100%
    ----------------------------------------------------
-   TOTAL                               73      5    93%
+   TOTAL                               73      0   100%

examples/miniapps/ghnav-flask/githubnavigator/application.py

@@ -1,39 +1,16 @@
 """Application module."""
 
-from dependency_injector import containers, providers
-from dependency_injector.ext import flask
-from github import Github
-
-from . import services, views
+from .containers import ApplicationContainer
 
 
-class Application(containers.DeclarativeContainer):
-    """Application container."""
+def create_app():
+    """Create and return Flask application."""
+    container = ApplicationContainer()
+    container.config.from_yaml('config.yml')
 
-    config = providers.Configuration()
+    app = container.app()
+    app.container = container
 
-    github_client = providers.Factory(
-        Github,
-        login_or_token=config.github.auth_token,
-        timeout=config.github.request_timeout,
-    )
+    app.add_url_rule('/', view_func=container.index_view.as_view())
 
-    search_service = providers.Factory(
-        services.SearchService,
-        github_client=github_client,
-    )
-
-    index_view = providers.Callable(
-        views.index,
-        search_service=search_service,
-        default_search_term=config.search.default_term,
-        default_search_limit=config.search.default_limit,
-    )
-
-    app = providers.Factory(
-        flask.create_app,
-        name=__name__,
-        routes=[
-            flask.Route('/', view_provider=index_view),
-        ],
-    )
+    return app

examples/miniapps/ghnav-flask/githubnavigator/containers.py

@@ -0,0 +1,34 @@
+"""Application containers module."""
+
+from dependency_injector import containers, providers
+from dependency_injector.ext import flask
+from flask import Flask
+from github import Github
+
+from . import views, services
+
+
+class ApplicationContainer(containers.DeclarativeContainer):
+    """Application container."""
+
+    app = flask.Application(Flask, __name__)
+
+    config = providers.Configuration()
+
+    github_client = providers.Factory(
+        Github,
+        login_or_token=config.github.auth_token,
+        timeout=config.github.request_timeout,
+    )
+
+    search_service = providers.Factory(
+        services.SearchService,
+        github_client=github_client,
+    )
+
+    index_view = flask.View(
+        views.index,
+        search_service=search_service,
+        default_search_term=config.search.default_term,
+        default_search_limit=config.search.default_limit,
+    )

examples/miniapps/ghnav-flask/githubnavigator/entrypoint.py

@@ -1,9 +0,0 @@
-"""Entrypoint module."""
-
-from .application import Application
-
-
-application = Application()
-application.config.from_yaml('config.yml')
-application.config.github.auth_token.from_env('GITHUB_TOKEN')
-app = application.app()

examples/miniapps/ghnav-flask/githubnavigator/services.py

@@ -20,6 +20,7 @@ class SearchService:
         ]
 
     def _format_repo(self, repository: Repository):
+        commits = repository.get_commits()
         return {
             'url': repository.html_url,
             'name': repository.name,
@@ -29,7 +30,7 @@ class SearchService:
                 'avatar_url': repository.owner.avatar_url,
             },
             'created_at': repository.created_at,
-            'latest_commit': self._format_commit(repository.get_commits()[0]),
+            'latest_commit': self._format_commit(commits[0]) if commits else {},
         }
 
     def _format_commit(self, commit: Commit):

examples/miniapps/ghnav-flask/githubnavigator/tests.py

@@ -6,33 +6,15 @@ import pytest
 from github import Github
 from flask import url_for
 
-from .application import Application
+from .application import create_app
 
 
 @pytest.fixture
-def application():
-    application = Application()
-    application.config.from_dict(
-        {
-            'github': {
-                'auth_token': 'test-token',
-                'request_timeout': 10,
-            },
-            'search': {
-                'default_term': 'Dependency Injector',
-                'default_limit': 5,
-            },
-        }
-    )
-    return application
+def app():
+    return create_app()
 
 
-@pytest.fixture()
-def app(application: Application):
-    return application.app()
-
-
-def test_index(client, application: Application):
+def test_index(client, app):
     github_client_mock = mock.Mock(spec=Github)
     github_client_mock.search_repositories.return_value = [
         mock.Mock(
@@ -59,7 +41,7 @@ def test_index(client, application: Application):
         ),
     ]
 
-    with application.github_client.override(github_client_mock):
+    with app.container.github_client.override(github_client_mock):
         response = client.get(url_for('index'))
 
     assert response.status_code == 200
@@ -79,11 +61,11 @@ def test_index(client, application: Application):
     assert b'repo2-created-at' in response.data
 
 
-def test_index_no_results(client, application: Application):
+def test_index_no_results(client, app):
     github_client_mock = mock.Mock(spec=Github)
     github_client_mock.search_repositories.return_value = []
 
-    with application.github_client.override(github_client_mock):
+    with app.container.github_client.override(github_client_mock):
         response = client.get(url_for('index'))
 
     assert response.status_code == 200

src/dependency_injector/ext/flask.py

@@ -2,17 +2,36 @@
 
 from __future__ import absolute_import
 
-from flask import Flask
+from flask import request as flask_request
 
 from dependency_injector import providers, errors
 
 
-def create_app(name, routes, **kwargs):
-    """Create Flask app and add routes."""
-    app = Flask(name, **kwargs)
-    for route in routes:
-        app.add_url_rule(*route.args, **route.options)
-    return app
+request = providers.Object(flask_request)
+
+
+class Application(providers.Singleton):
+    """Flask application provider."""
+
+
+class Extension(providers.Singleton):
+    """Flask extension provider."""
+
+
+class View(providers.Callable):
+    """Flask view provider."""
+
+    def as_view(self):
+        """Return Flask view function."""
+        return as_view(self)
+
+
+class ClassBasedView(providers.Factory):
+    """Flask class-based view provider."""
+
+    def as_view(self, name):
+        """Return Flask view function."""
+        return as_view(self, name)
 
 
 def as_view(provider, name=None):
@@ -49,35 +68,3 @@ def as_view(provider, name=None):
         view.provide_automatic_options = provider.provides.provide_automatic_options
 
     return view
-
-
-class Route:
-    """Route is a glue for Dependency Injector providers and Flask views."""
-
-    def __init__(
-            self,
-            rule,
-            endpoint=None,
-            view_provider=None,
-            provide_automatic_options=None,
-            **options):
-        """Initialize route."""
-        self.view_provider = view_provider
-        self.args = (rule, endpoint, as_view(view_provider, endpoint), provide_automatic_options)
-        self.options = options
-
-    def __deepcopy__(self, memo):
-        """Create and return full copy of provider."""
-        copied = memo.get(id(self))
-        if copied is not None:
-            return copied
-
-        rule, endpoint, _, provide_automatic_options = self.args
-        view_provider = providers.deepcopy(self.view_provider, memo)
-
-        return self.__class__(
-            rule,
-            endpoint,
-            view_provider,
-            provide_automatic_options,
-            **self.options)

tests/unit/ext/test_flask_py2_py3.py

@@ -1,7 +1,7 @@
 """Dependency injector Flask extension unit tests."""
 
 import unittest2 as unittest
-from flask import url_for
+from flask import Flask, url_for
 from flask.views import MethodView
 
 from dependency_injector import containers, providers
@@ -21,28 +21,29 @@ class Test(MethodView):
         return 'Test class-based!'
 
 
-class Application(containers.DeclarativeContainer):
+class ApplicationContainer(containers.DeclarativeContainer):
 
-    index_view = providers.Callable(index)
-    test_view = providers.Callable(test)
-    test_class_view = providers.Factory(Test)
+    app = flask.Application(Flask, __name__)
 
-    app = providers.Factory(
-        flask.create_app,
-        name=__name__,
-        routes=[
-            flask.Route('/', view_provider=index_view),
-            flask.Route('/test', 'test-test', test_view),
-            flask.Route('/test-class', 'test-class', test_class_view)
-        ],
-    )
+    index_view = flask.View(index)
+    test_view = flask.View(test)
+    test_class_view = flask.ClassBasedView(Test)
+
+
+def create_app():
+    container = ApplicationContainer()
+    app = container.app()
+    app.container = container
+    app.add_url_rule('/', view_func=container.index_view.as_view())
+    app.add_url_rule('/test', 'test-test', view_func=container.test_view.as_view())
+    app.add_url_rule('/test-class', view_func=container.test_class_view.as_view('test-class'))
+    return app
 
 
 class ApplicationTests(unittest.TestCase):
 
     def setUp(self):
-        application = Application()
-        self.app = application.app()
+        self.app = create_app()
         self.app.config['SERVER_NAME'] = 'test-server.com'
         self.client = self.app.test_client()
         self.client.__enter__()