Rework movie lister example app

examples/miniapps/movie-lister/README.rst

@@ -0,0 +1,67 @@
+Movie lister - a naive example of dependency injection in Python
+================================================================
+
+This is a Python implementation of the dependency injection example from Martin Fowler's
+article about dependency injection and inversion of control:
+
+    http://www.martinfowler.com/articles/injection.html
+
+Create virtual environment:
+
+.. code-block:: bash
+
+   virtualenv venv
+   . venv/bin/activate
+
+Install requirements:
+
+.. code-block:: bash
+
+    pip install -r requirements.txt
+
+To run the application do:
+
+.. code-block:: bash
+
+   MOVIE_STORAGE_TYPE=csv python -m movies
+   MOVIE_STORAGE_TYPE=sqlite python -m movies
+
+The output should be something like:
+
+.. code-block:: bash
+
+   [Movie(name='The Hunger Games: Mockingjay - Part 2', year=2015, director='Francis Lawrence')]
+   [Movie(name='The 33', year=2015, director='Patricia Riggen')]
+   [Movie(name='Star Wars: Episode VII - The Force Awakens', year=2015, director='JJ Abrams')]
+   [Movie(name='The Hunger Games: Mockingjay - Part 2', year=2015, director='Francis Lawrence'), Movie(name='The 33', year=2015, director='Patricia Riggen'), Movie(name='Star Wars: Episode VII - The Force Awakens', year=2015, director='JJ Abrams')]
+
+To run the tests do:
+
+.. code-block:: bash
+
+   pytest movies/tests.py --cov=movies
+
+The output should be something like:
+
+.. code-block::
+
+   platform darwin -- Python 3.8.3, pytest-5.4.3, py-1.9.0, pluggy-0.13.1
+   plugins: cov-2.10.0
+   collected 2 items
+
+   movies/tests.py ..                                              [100%]
+
+   ---------- coverage: platform darwin, python 3.8.3-final-0 -----------
+   Name                   Stmts   Miss  Cover
+   ------------------------------------------
+   movies/__init__.py         0      0   100%
+   movies/__main__.py        15     15     0%
+   movies/containers.py       9      0   100%
+   movies/finders.py          9      0   100%
+   movies/fixtures.py         1      0   100%
+   movies/listers.py          8      0   100%
+   movies/models.py           7      1    86%
+   movies/storages.py        32     17    47%
+   movies/tests.py           24      0   100%
+   ------------------------------------------
+   TOTAL                    105     33    69%

examples/miniapps/movie-lister/config.yml

@@ -0,0 +1,8 @@
+storage:
+
+  csv:
+    path: "data/movies.csv"
+    delimiter: ","
+
+  sqlite:
+    path: "data/movies.db"

examples/miniapps/movie-lister/movies/__init__.py

@@ -0,0 +1 @@
+"""Top-level package."""

examples/miniapps/movie-lister/movies/__main__.py

@@ -0,0 +1,23 @@
+"""Main module."""
+
+from .containers import ApplicationContainer
+
+
+def main():
+    container = ApplicationContainer()
+    container.config.from_yaml('config.yml')
+    container.config.storage.type.from_env('MOVIE_STORAGE_TYPE')
+
+    storage = container.storage()
+    fixtures = container.fixtures()
+    storage.load_all(fixtures)
+
+    lister = container.lister()
+    print(lister.movies_directed_by('Francis Lawrence'))
+    print(lister.movies_directed_by('Patricia Riggen'))
+    print(lister.movies_directed_by('JJ Abrams'))
+    print(lister.movies_released_in(2015))
+
+
+if __name__ == '__main__':
+    main()

examples/miniapps/movie-lister/movies/containers.py

@@ -0,0 +1,39 @@
+"""Containers module."""
+
+from dependency_injector import containers, providers
+
+from . import finders, listers, storages, models, fixtures
+
+
+class ApplicationContainer(containers.DeclarativeContainer):
+
+    config = providers.Configuration()
+
+    fixtures = providers.Object(fixtures.MOVIES_SAMPLE_DATA)
+
+    storage = providers.Singleton(
+        providers.Selector(
+            config.storage.type,
+            csv=providers.Factory(
+                storages.CsvMovieStorage,
+                options=config.storage[config.storage.type],
+            ),
+            sqlite=providers.Factory(
+                storages.SqliteMovieStorage,
+                options=config.storage[config.storage.type],
+            ),
+        ),
+    )
+
+    movie = providers.Factory(models.Movie)
+
+    finder = providers.Factory(
+        finders.MovieFinder,
+        movie_factory=movie.provider,
+        movie_storage=storage,
+    )
+
+    lister = providers.Factory(
+        listers.MovieLister,
+        movie_finder=finder,
+    )

examples/miniapps/movie-lister/movies/finders.py

@@ -0,0 +1,23 @@
+"""Movie finders module."""
+
+from typing import Callable, List
+
+from .models import Movie
+from .storages import MovieStorage
+
+
+class MovieFinder:
+
+    def __init__(
+            self,
+            movie_factory: Callable[..., Movie],
+            movie_storage: MovieStorage,
+    ) -> None:
+        self._movie_factory = movie_factory
+        self._movie_storage = movie_storage
+
+    def find_all(self) -> List[Movie]:
+        return [
+            self._movie_factory(*row)
+            for row in self._movie_storage.get_all()
+        ]

examples/miniapps/movie-lister/movies/fixtures.py

@@ -1,8 +1,8 @@
 """Fixtures module."""
 
 
-MOVIES_SAMPLE_DATA = (
+MOVIES_SAMPLE_DATA = [
     ('The Hunger Games: Mockingjay - Part 2', 2015, 'Francis Lawrence'),
     ('The 33', 2015, 'Patricia Riggen'),
     ('Star Wars: Episode VII - The Force Awakens', 2015, 'JJ Abrams'),
-)
+]

examples/miniapps/movie-lister/movies/listers.py

@@ -0,0 +1,21 @@
+"""Movie listers module."""
+
+from .finders import MovieFinder
+
+
+class MovieLister:
+
+    def __init__(self, movie_finder: MovieFinder):
+        self._movie_finder = movie_finder
+
+    def movies_directed_by(self, director):
+        return [
+            movie for movie in self._movie_finder.find_all()
+            if movie.director == director
+        ]
+
+    def movies_released_in(self, year):
+        return [
+            movie for movie in self._movie_finder.find_all()
+            if movie.year == year
+        ]

examples/miniapps/movie-lister/movies/models.py

@@ -0,0 +1,16 @@
+"""Movie module."""
+
+
+class Movie:
+
+    def __init__(self, name: str, year: int, director: str):
+        self.name = str(name)
+        self.year = int(year)
+        self.director = str(director)
+
+    def __repr__(self):
+        return '{0}(name={1}, year={2}, director={3})'.format(
+            self.__class__.__name__,
+            repr(self.name),
+            repr(self.year),
+            repr(self.director))

examples/miniapps/movie-lister/movies/storages.py

@@ -0,0 +1,55 @@
+"""Movie storages module."""
+
+import csv
+import sqlite3
+from typing import List, Tuple, Any
+
+Row = Tuple[Any]
+
+
+class MovieStorage:
+
+    def load_all(self, movie_data: List[Row]):
+        raise NotImplementedError()
+
+    def get_all(self) -> List[Row]:
+        raise NotImplementedError()
+
+
+class CsvMovieStorage(MovieStorage):
+
+    def __init__(self, options) -> None:
+        self._csv_file_path = options.pop('path')
+        self._delimiter = options.pop('delimiter')
+
+    def load_all(self, movie_data: List[Row]) -> None:
+        with open(self._csv_file_path, 'w') as csv_file:
+            csv.writer(csv_file, delimiter=self._delimiter).writerows(movie_data)
+
+    def get_all(self) -> List[Row]:
+        with open(self._csv_file_path) as csv_file:
+            csv_reader = csv.reader(csv_file, delimiter=self._delimiter)
+            return [row for row in csv_reader]
+
+
+class SqliteMovieStorage(MovieStorage):
+
+    def __init__(self, options) -> None:
+        self._database = sqlite3.connect(database=options.pop('path'))
+
+    def load_all(self, movie_data: List[Row]) -> None:
+        with self._database as db:
+            db.execute(
+                'CREATE TABLE IF NOT EXISTS movies '
+                '(name text, year int, director text)',
+            )
+            db.execute('DELETE FROM movies')
+            db.executemany('INSERT INTO movies VALUES (?,?,?)', movie_data)
+
+    def get_all(self) -> List[Row]:
+        with self._database as db:
+            rows = db.execute(
+                'SELECT name, year, director '
+                'FROM movies',
+            )
+            return [row for row in rows]

examples/miniapps/movie-lister/movies/tests.py

@@ -0,0 +1,55 @@
+"""Tests module."""
+
+from unittest import mock
+
+import pytest
+
+from .containers import ApplicationContainer
+
+
+@pytest.fixture
+def container():
+    container = ApplicationContainer()
+    container.config.from_dict({
+        'storage': {
+            'type': 'csv',
+            'csv': {
+                'path': '/fake-movies.csv',
+                'delimiter': ',',
+            },
+            'sqlite': {
+                'path': '/fake-movies.db',
+            },
+        },
+    })
+    return container
+
+
+def test_movies_directed_by(container):
+    storage_mock = mock.Mock()
+    storage_mock.get_all.return_value = [
+        ('The 33', 2015, 'Patricia Riggen'),
+        ('The Jungle Book', 2016, 'Jon Favreau'),
+    ]
+
+    with container.storage.override(storage_mock):
+        lister = container.lister()
+        movies = lister.movies_directed_by('Jon Favreau')
+
+    assert len(movies) == 1
+    assert movies[0].name == 'The Jungle Book'
+
+
+def test_movies_released_in(container):
+    storage_mock = mock.Mock()
+    storage_mock.get_all.return_value = [
+        ('The 33', 2015, 'Patricia Riggen'),
+        ('The Jungle Book', 2016, 'Jon Favreau'),
+    ]
+
+    with container.storage.override(storage_mock):
+        lister = container.lister()
+        movies = lister.movies_released_in(2015)
+
+    assert len(movies) == 1
+    assert movies[0].name == 'The 33'

examples/miniapps/movie-lister/requirements.txt

@@ -0,0 +1,4 @@
+dependency-injector
+pyyaml
+pytest
+pytest-cov

examples/miniapps/movie_lister/README.rst

@@ -1,16 +0,0 @@
-A naive example of dependency injection in Python
-=================================================
-
-Example implementation of dependency injection on Python from Martin Fowler's
-article about dependency injection and inversion of control:
-
-http://www.martinfowler.com/articles/injection.html
-
-
-Instructions for running:
-
-.. code-block:: bash
-
-    python app_csv.py
-    python app_db.py
-    python app_db_csv.py

examples/miniapps/movie_lister/app_csv.py

@@ -1,49 +0,0 @@
-"""A naive example of dependency injection on Python.
-
-Example implementation of dependency injection in Python from Martin Fowler's
-article about dependency injection and inversion of control:
-
-http://www.martinfowler.com/articles/injection.html
-
-This mini application uses ``movies`` library, that is configured to work with
-csv file movies database.
-"""
-
-import movies
-import movies.finders
-
-import example.db
-import example.main
-
-import settings
-import fixtures
-
-import dependency_injector.containers as containers
-import dependency_injector.providers as providers
-
-
-@containers.override(movies.MoviesModule)
-class MyMoviesModule(containers.DeclarativeContainer):
-    """IoC container for overriding movies module component providers."""
-
-    finder = providers.Factory(movies.finders.CsvMovieFinder,
-                               csv_file_path=settings.MOVIES_CSV_PATH,
-                               delimiter=',',
-                               **movies.MoviesModule.finder.kwargs)
-
-
-class CsvApplication(containers.DeclarativeContainer):
-    """IoC container of csv application component providers."""
-
-    main = providers.Callable(example.main.main,
-                              movie_lister=movies.MoviesModule.lister)
-
-    init_db = providers.Callable(example.db.init_csv,
-                                 movies_data=fixtures.MOVIES_SAMPLE_DATA,
-                                 csv_file_path=settings.MOVIES_CSV_PATH,
-                                 delimiter=',')
-
-
-if __name__ == '__main__':
-    CsvApplication.init_db()
-    CsvApplication.main()

examples/miniapps/movie_lister/app_db.py

@@ -1,55 +0,0 @@
-"""A naive example of dependency injection on Python.
-
-Example implementation of dependency injection in Python from Martin Fowler's
-article about dependency injection and inversion of control:
-
-http://www.martinfowler.com/articles/injection.html
-
-This mini application uses ``movies`` library, that is configured to work with
-sqlite movies database.
-"""
-
-import sqlite3
-
-import movies
-import movies.finders
-
-import example.db
-import example.main
-
-import settings
-import fixtures
-
-import dependency_injector.containers as containers
-import dependency_injector.providers as providers
-
-
-class ResourcesModule(containers.DeclarativeContainer):
-    """IoC container of application resource providers."""
-
-    database = providers.Singleton(sqlite3.connect, settings.MOVIES_DB_PATH)
-
-
-@containers.override(movies.MoviesModule)
-class MyMoviesModule(containers.DeclarativeContainer):
-    """IoC container for overriding movies module component providers."""
-
-    finder = providers.Factory(movies.finders.SqliteMovieFinder,
-                               database=ResourcesModule.database,
-                               **movies.MoviesModule.finder.kwargs)
-
-
-class DbApplication(containers.DeclarativeContainer):
-    """IoC container of database application component providers."""
-
-    main = providers.Callable(example.main.main,
-                              movie_lister=movies.MoviesModule.lister)
-
-    init_db = providers.Callable(example.db.init_sqlite,
-                                 movies_data=fixtures.MOVIES_SAMPLE_DATA,
-                                 database=ResourcesModule.database)
-
-
-if __name__ == '__main__':
-    DbApplication.init_db()
-    DbApplication.main()

examples/miniapps/movie_lister/app_db_csv.py

@@ -1,80 +0,0 @@
-"""A naive example of dependency injection on Python.
-
-Example implementation of dependency injection in Python from Martin Fowler's
-article about dependency injection and inversion of control:
-
-http://www.martinfowler.com/articles/injection.html
-
-This mini application uses ``movies`` library, that is configured to work with
-sqlite movies database and csv file movies database.
-"""
-
-import sqlite3
-
-import movies
-import movies.finders
-
-import example.db
-import example.main
-
-import settings
-import fixtures
-
-import dependency_injector.containers as containers
-import dependency_injector.providers as providers
-
-
-class ResourcesModule(containers.DeclarativeContainer):
-    """IoC container of application resource providers."""
-
-    database = providers.Singleton(sqlite3.connect, settings.MOVIES_DB_PATH)
-
-
-@containers.copy(movies.MoviesModule)
-class DbMoviesModule(movies.MoviesModule):
-    """IoC container for overriding movies module component providers."""
-
-    finder = providers.Factory(movies.finders.SqliteMovieFinder,
-                               database=ResourcesModule.database,
-                               **movies.MoviesModule.finder.kwargs)
-
-
-@containers.copy(movies.MoviesModule)
-class CsvMoviesModule(movies.MoviesModule):
-    """IoC container for overriding movies module component providers."""
-
-    finder = providers.Factory(movies.finders.CsvMovieFinder,
-                               csv_file_path=settings.MOVIES_CSV_PATH,
-                               delimiter=',',
-                               **movies.MoviesModule.finder.kwargs)
-
-
-class DbApplication(containers.DeclarativeContainer):
-    """IoC container of database application component providers."""
-
-    main = providers.Callable(example.main.main,
-                              movie_lister=DbMoviesModule.lister)
-
-    init_db = providers.Callable(example.db.init_sqlite,
-                                 movies_data=fixtures.MOVIES_SAMPLE_DATA,
-                                 database=ResourcesModule.database)
-
-
-class CsvApplication(containers.DeclarativeContainer):
-    """IoC container of csv application component providers."""
-
-    main = providers.Callable(example.main.main,
-                              movie_lister=CsvMoviesModule.lister)
-
-    init_db = providers.Callable(example.db.init_csv,
-                                 movies_data=fixtures.MOVIES_SAMPLE_DATA,
-                                 csv_file_path=settings.MOVIES_CSV_PATH,
-                                 delimiter=',')
-
-
-if __name__ == '__main__':
-    DbApplication.init_db()
-    DbApplication.main()
-
-    CsvApplication.init_db()
-    CsvApplication.main()

examples/miniapps/movie_lister/data/movies.csv

@@ -1,3 +0,0 @@
-The Hunger Games: Mockingjay - Part 2,2015,Francis Lawrence
-The 33,2015,Patricia Riggen
-Star Wars: Episode VII - The Force Awakens,2015,JJ Abrams

examples/miniapps/movie_lister/example/__init__.py

@@ -1 +0,0 @@
-"""Example top-level package."""

examples/miniapps/movie_lister/example/db.py

@@ -1,35 +0,0 @@
-"""Example database module."""
-
-import csv
-
-
-def init_sqlite(movies_data, database):
-    """Initialize sqlite3 movies database.
-
-    :param movies_data: Data about movies
-    :type movies_data: tuple[tuple]
-
-    :param database: Connection to sqlite database with movies data
-    :type database: sqlite3.Connection
-    """
-    with database:
-        database.execute('CREATE TABLE IF NOT EXISTS movies '
-                         '(name text, year int, director text)')
-        database.execute('DELETE FROM movies')
-        database.executemany('INSERT INTO movies VALUES (?,?,?)', movies_data)
-
-
-def init_csv(movies_data, csv_file_path, delimiter):
-    """Initialize csv movies database.
-
-    :param movies_data: Data about movies
-    :type movies_data: tuple[tuple]
-
-    :param csv_file_path: Path to csv file with movies data
-    :type csv_file_path: str
-
-    :param delimiter: Csv file's delimiter
-    :type delimiter: str
-    """
-    with open(csv_file_path, 'w') as csv_file:
-        csv.writer(csv_file, delimiter=delimiter).writerows(movies_data)

examples/miniapps/movie_lister/example/main.py

@@ -1,17 +0,0 @@
-"""Example main module."""
-
-
-def main(movie_lister):
-    """Run application.
-
-    This program prints info about all movies that were directed by different
-    persons and then prints all movies that were released in 2015.
-
-    :param movie_lister: Movie lister instance
-    :type movie_lister: movies.listers.MovieLister
-    """
-    print(movie_lister.movies_directed_by('Francis Lawrence'))
-    print(movie_lister.movies_directed_by('Patricia Riggen'))
-    print(movie_lister.movies_directed_by('JJ Abrams'))
-
-    print(movie_lister.movies_released_in(2015))

examples/miniapps/movie_lister/movies/__init__.py

@@ -1,32 +0,0 @@
-"""Movies package.
-
-Top-level package of movies library. This package contains IoC container of
-movies module component providers - ``MoviesModule``. It is recommended to use
-movies library functionality by fetching required instances from
-``MoviesModule`` providers.
-
-``MoviesModule.finder`` is a factory that provides abstract component
-``finders.MovieFinder``. This provider should be overridden by provider of
-concrete finder implementation in terms of library configuration.
-
-Each of ``MoviesModule`` providers could be overridden.
-"""
-
-import movies.finders
-import movies.listers
-import movies.models
-
-import dependency_injector.containers as containers
-import dependency_injector.providers as providers
-
-
-class MoviesModule(containers.DeclarativeContainer):
-    """IoC container of movies module component providers."""
-
-    movie = providers.Factory(movies.models.Movie)
-
-    finder = providers.AbstractFactory(movies.finders.MovieFinder,
-                                       movie_model=movie.provider)
-
-    lister = providers.Factory(movies.listers.MovieLister,
-                               movie_finder=finder)

examples/miniapps/movie_lister/movies/finders.py

@@ -1,87 +0,0 @@
-"""Movie finders module.
-
-This module contains all finder implementations.
-"""
-
-import csv
-
-
-class MovieFinder:
-    """Movie finder component.
-
-    Movie finder component is responsible for fetching movies data from
-    various storage.
-    """
-
-    def __init__(self, movie_model):
-        """Initialize instance.
-
-        :param movie_model: Movie model's factory
-        :type movie_model: movies.models.Movie
-        """
-        self._movie_model = movie_model
-
-    def find_all(self):
-        """Return all found movies.
-
-        :rtype: list[movies.models.Movie]
-        :return: List of movie instances.
-        """
-        raise NotImplementedError()
-
-
-class CsvMovieFinder(MovieFinder):
-    """Movie finder that fetches movies data from csv file."""
-
-    def __init__(self, movie_model, csv_file_path, delimiter):
-        """Initialize instance.
-
-        :param movie_model: Movie model's factory
-        :type movie_model: movies.models.Movie
-
-        :param csv_file_path: Path to csv file with movies data
-        :type csv_file_path: str
-
-        :param delimiter: Csv file's delimiter
-        :type delimiter: str
-        """
-        self._csv_file_path = csv_file_path
-        self._delimiter = delimiter
-        super().__init__(movie_model)
-
-    def find_all(self):
-        """Return all found movies.
-
-        :rtype: list[movies.models.Movie]
-        :return: List of movie instances.
-        """
-        with open(self._csv_file_path) as csv_file:
-            csv_reader = csv.reader(csv_file, delimiter=self._delimiter)
-            return [self._movie_model(*row) for row in csv_reader]
-
-
-class SqliteMovieFinder(MovieFinder):
-    """Movie finder that fetches movies data from sqlite database."""
-
-    def __init__(self, movie_model, database):
-        """Initialize instance.
-
-        :param movie_model: Movie model's factory
-        :type movie_model: (object) -> movies.models.Movie
-
-        :param database: Connection to sqlite database with movies data
-        :type database: sqlite3.Connection
-        """
-        self._database = database
-        super().__init__(movie_model)
-
-    def find_all(self):
-        """Return all found movies.
-
-        :rtype: list[movies.models.Movie]
-        :return: List of movie instances.
-        """
-        with self._database:
-            rows = self._database.execute('SELECT name, year, director '
-                                          'FROM movies')
-            return [self._movie_model(*row) for row in rows]

examples/miniapps/movie_lister/movies/listers.py

@@ -1,44 +0,0 @@
-"""Movie listers module.
-
-This module contains all lister implementations.
-"""
-
-
-class MovieLister:
-    """Movie lister component.
-
-    Movie lister component provides several methods for filtering movies by
-    specific criteria.
-    """
-
-    def __init__(self, movie_finder):
-        """Initialize instance.
-
-        :param movie_finder: Movie finder instance
-        :type movie_finder: movies.finders.MovieFinder
-        """
-        self._movie_finder = movie_finder
-
-    def movies_directed_by(self, director):
-        """Return list of movies that were directed by certain person.
-
-        :param director: Director's name
-        :type director: str
-
-        :rtype: list[movies.models.Movie]
-        :return: List of movie instances.
-        """
-        return [movie for movie in self._movie_finder.find_all()
-                if movie.director == director]
-
-    def movies_released_in(self, year):
-        """Return list of movies that were released in certain year.
-
-        :param year: Release year
-        :type year: int
-
-        :rtype: list[movies.models.Movie]
-        :return: List of movie instances.
-        """
-        return [movie for movie in self._movie_finder.find_all()
-                if movie.year == year]

examples/miniapps/movie_lister/movies/models.py

@@ -1,36 +0,0 @@
-"""Movie models module.
-
-This module contains all model implementations.
-"""
-
-
-class Movie:
-    """Base movie model."""
-
-    def __init__(self, name, year, director):
-        """Initialize instance.
-
-        :param name: Movie's name
-        :type name: str
-
-        :param year: Year, when movie was released
-        :type year: int
-
-        :param director: Name of person, that directed the movie
-        :type director: str
-        """
-        self.name = str(name)
-        self.year = int(year)
-        self.director = str(director)
-
-    def __repr__(self):
-        """Return string representation of movie instance.
-
-        :rtype: str
-        :return: Movie's string representation.
-        """
-        return '{0}(name={1}, year={2}, director={3})'.format(
-            self.__class__.__name__,
-            repr(self.name),
-            repr(self.year),
-            repr(self.director))

examples/miniapps/movie_lister/settings.py

@@ -1,11 +0,0 @@
-"""Settings module.
-
-This module contains application's settings and constants.
-"""
-
-import os
-
-
-DATA_DIR = os.path.abspath(os.path.dirname(__file__) + '/data')
-MOVIES_CSV_PATH = DATA_DIR + '/movies.csv'
-MOVIES_DB_PATH = DATA_DIR + '/movies.db'