Update services example

README.rst

@@ -58,9 +58,11 @@ system that consists from several business and platform services:
 
 .. code-block:: python
 
-    """Example of several Dependency Injector IoC containers."""
+    """Example of dependency injection in Python."""
 
+    import logging
     import sqlite3
+
     import boto.s3.connection
 
     import example.main
@@ -73,6 +75,8 @@ system that consists from several business and platform services:
     class Platform(containers.DeclarativeContainer):
         """IoC container of platform service providers."""
 
+        logger = providers.Singleton(logging.Logger, name='example')
+
         database = providers.Singleton(sqlite3.connect, ':memory:')
 
         s3 = providers.Singleton(boto.s3.connection.S3Connection,
@@ -84,13 +88,16 @@ system that consists from several business and platform services:
         """IoC container of business service providers."""
 
         users = providers.Factory(example.services.Users,
+                                  logger=Platform.logger,
                                   db=Platform.database)
 
         auth = providers.Factory(example.services.Auth,
+                                 logger=Platform.logger,
                                  db=Platform.database,
                                  token_ttl=3600)
 
         photos = providers.Factory(example.services.Photos,
+                                   logger=Platform.logger,
                                    db=Platform.database,
                                    s3=Platform.s3)
 
@@ -107,25 +114,52 @@ Next example demonstrates usage of IoC containers & providers defined above:
 
 .. code-block:: python
 
-    """Run example application."""
+    """Run dependency injection example application.
 
-    import containers
+    Instructions for running:
+
+        python run.py 1 secret photo.jpg
+    """
+
+    import sys
+    import logging
+
+    from containers import Platform, Application
 
 
     if __name__ == '__main__':
-        containers.Application.main()
+        # Configure platform logger:
+        Platform.logger().addHandler(logging.StreamHandler(sys.stdout))
+
+        # Run application:
+        Application.main(uid=sys.argv[1],
+                         password=sys.argv[2],
+                         photo=sys.argv[3])
 
         # Previous call is an equivalent of next operations:
         #
+        # logger = logging.Logger(name='example')
         # database = sqlite3.connect(':memory:')
         # s3 = boto.s3.connection.S3Connection(aws_access_key_id='KEY',
         #                                      aws_secret_access_key='SECRET')
         #
-        # example.main.main(users_service=example.services.Users(db=database),
+        # example.main.main(uid=sys.argv[1],
-        #                   auth_service=example.services.Auth(db=database,
+        #                   password=sys.argv[2],
+        #                   photo=sys.argv[3],
+        #                   users_service=example.services.Users(logger=logger,
+        #                                                        db=database),
+        #                   auth_service=example.services.Auth(logger=logger,
+        #                                                      db=database,
         #                                                      token_ttl=3600),
-        #                   photos_service=example.services.Photos(db=database,
+        #                   photos_service=example.services.Photos(logger=logger,
+        #                                                          db=database,
         #                                                          s3=s3))
+        #
+        # Output:
+        #
+        # User 1 has been found in database
+        # User 1 has been successfully authenticated
+        # Photo photo.jpg has been successfully uploaded by user 1
    
 Alternative definition styles
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

examples/miniapps/services/README.rst

@@ -5,4 +5,4 @@ Instructions for running
 
 .. code-block:: bash
 
-    python run.py
+    python run.py 1 secret photo.jpg

examples/miniapps/services/containers.py

@@ -1,6 +1,8 @@
-"""Example of several Dependency Injector IoC containers."""
+"""Example of dependency injection in Python."""
 
+import logging
 import sqlite3
+
 import boto.s3.connection
 
 import example.main
@@ -13,6 +15,8 @@ import dependency_injector.providers as providers
 class Platform(containers.DeclarativeContainer):
     """IoC container of platform service providers."""
 
+    logger = providers.Singleton(logging.Logger, name='example')
+
     database = providers.Singleton(sqlite3.connect, ':memory:')
 
     s3 = providers.Singleton(boto.s3.connection.S3Connection,
@@ -24,13 +28,16 @@ class Services(containers.DeclarativeContainer):
     """IoC container of business service providers."""
 
     users = providers.Factory(example.services.Users,
+                              logger=Platform.logger,
                               db=Platform.database)
 
     auth = providers.Factory(example.services.Auth,
+                             logger=Platform.logger,
                              db=Platform.database,
                              token_ttl=3600)
 
     photos = providers.Factory(example.services.Photos,
+                               logger=Platform.logger,
                                db=Platform.database,
                                s3=Platform.s3)
 

examples/miniapps/services/containers_alt_syntax_1.py

@@ -1,9 +1,11 @@
-"""Example of several Dependency Injector IoC containers.
+"""Example of dependency injection in Python.
 
 Alternative injections definition style #1.
 """
 
+import logging
 import sqlite3
+
 import boto.s3.connection
 
 import example.main
@@ -16,6 +18,9 @@ import dependency_injector.providers as providers
 class Platform(containers.DeclarativeContainer):
     """IoC container of platform service providers."""
 
+    logger = providers.Singleton(logging.Logger) \
+        .add_kwargs(name='example')
+
     database = providers.Singleton(sqlite3.connect) \
         .add_args(':memory:')
 
@@ -28,14 +33,17 @@ class Services(containers.DeclarativeContainer):
     """IoC container of business service providers."""
 
     users = providers.Factory(example.services.Users) \
-        .add_kwargs(db=Platform.database)
+        .add_kwargs(logger=Platform.logger,
+                    db=Platform.database)
 
     auth = providers.Factory(example.services.Auth) \
-        .add_kwargs(db=Platform.database,
+        .add_kwargs(logger=Platform.logger,
+                    db=Platform.database,
                     token_ttl=3600)
 
     photos = providers.Factory(example.services.Photos) \
-        .add_kwargs(db=Platform.database,
+        .add_kwargs(logger=Platform.logger,
+                    db=Platform.database,
                     s3=Platform.s3)
 
 

examples/miniapps/services/containers_alt_syntax_2.py

@@ -1,9 +1,11 @@
-"""Example of several Dependency Injector IoC containers.
+"""Example of dependency injection in Python.
 
 Alternative injections definition style #2.
 """
 
+import logging
 import sqlite3
+
 import boto.s3.connection
 
 import example.main
@@ -16,6 +18,9 @@ import dependency_injector.providers as providers
 class Platform(containers.DeclarativeContainer):
     """IoC container of platform service providers."""
 
+    logger = providers.Singleton(logging.Logger)
+    logger.add_kwargs(name='example')
+
     database = providers.Singleton(sqlite3.connect)
     database.add_args(':memory:')
 
@@ -28,14 +33,17 @@ class Services(containers.DeclarativeContainer):
     """IoC container of business service providers."""
 
     users = providers.Factory(example.services.Users)
-    users.add_kwargs(db=Platform.database)
+    users.add_kwargs(logger=Platform.logger,
+                     db=Platform.database)
 
     auth = providers.Factory(example.services.Auth)
-    auth.add_kwargs(db=Platform.database,
+    auth.add_kwargs(logger=Platform.logger,
+                    db=Platform.database,
                     token_ttl=3600)
 
     photos = providers.Factory(example.services.Photos)
-    photos.add_kwargs(db=Platform.database,
+    photos.add_kwargs(logger=Platform.logger,
+                      db=Platform.database,
                       s3=Platform.s3)
 
 

examples/miniapps/services/example/main.py

@@ -1,8 +1,8 @@
 """Example main module."""
 
 
-def main(users_service, auth_service, photos_service):
+def main(uid, password, photo, users_service, auth_service, photos_service):
     """Example main function."""
-    user = users_service.get_user('user')
+    user = users_service.get_user_by_id(uid)
-    auth_service.authenticate(user, 'secret')
+    auth_service.authenticate(user, password)
-    photos_service.upload_photo(user['id'], 'photo.jpg')
+    photos_service.upload_photo(user['uid'], photo)

examples/miniapps/services/example/services.py

@@ -4,37 +4,44 @@
 class Users(object):
     """Users service."""
 
-    def __init__(self, db):
+    def __init__(self, logger, db):
         """Initializer."""
+        self.logger = logger
         self.db = db
 
-    def get_user(self, login):
+    def get_user_by_id(self, uid):
         """Return user's information by login."""
-        return {'id': 1,
+        self.logger.debug('User %s has been found in database', uid)
-                'login': login,
+        return {'uid': uid,
                 'password_hash': 'secret_hash'}
 
 
 class Auth(object):
     """Auth service."""
 
-    def __init__(self, db, token_ttl):
+    def __init__(self, logger, db, token_ttl):
         """Initializer."""
+        self.logger = logger
         self.db = db
         self.token_ttl = token_ttl
 
     def authenticate(self, user, password):
         """Authenticate user."""
         assert user['password_hash'] == '_'.join((password, 'hash'))
+        self.logger.debug('User %s has been successfully authenticated',
+                          user['uid'])
 
 
 class Photos(object):
     """Photos service."""
 
-    def __init__(self, db, s3):
+    def __init__(self, logger, db, s3):
         """Initializer."""
+        self.logger = logger
         self.db = db
         self.s3 = s3
 
-    def upload_photo(self, user_id, photo_path):
+    def upload_photo(self, uid, photo_path):
         """Upload user photo."""
+        self.logger.debug('Photo %s has been successfully uploaded by user %s',
+                          photo_path, uid)

examples/miniapps/services/run.py

@@ -1,19 +1,46 @@
-"""Run example application."""
+"""Run dependency injection example application.
 
-import containers
+Instructions for running:
+
+    python run.py 1 secret photo.jpg
+"""
+
+import sys
+import logging
+
+from containers import Platform, Application
 
 
 if __name__ == '__main__':
-    containers.Application.main()
+    # Configure platform logger:
+    Platform.logger().addHandler(logging.StreamHandler(sys.stdout))
+
+    # Run application:
+    Application.main(uid=sys.argv[1],
+                     password=sys.argv[2],
+                     photo=sys.argv[3])
 
     # Previous call is an equivalent of next operations:
     #
+    # logger = logging.Logger(name='example')
     # database = sqlite3.connect(':memory:')
     # s3 = boto.s3.connection.S3Connection(aws_access_key_id='KEY',
     #                                      aws_secret_access_key='SECRET')
     #
-    # example.main.main(users_service=example.services.Users(db=database),
+    # example.main.main(uid=sys.argv[1],
-    #                   auth_service=example.services.Auth(db=database,
+    #                   password=sys.argv[2],
+    #                   photo=sys.argv[3],
+    #                   users_service=example.services.Users(logger=logger,
+    #                                                        db=database),
+    #                   auth_service=example.services.Auth(logger=logger,
+    #                                                      db=database,
     #                                                      token_ttl=3600),
-    #                   photos_service=example.services.Photos(db=database,
+    #                   photos_service=example.services.Photos(logger=logger,
+    #                                                          db=database,
     #                                                          s3=s3))
+    #
+    # Output:
+    #
+    # User 1 has been found in database
+    # User 1 has been successfully authenticated
+    # Photo photo.jpg has been successfully uploaded by user 1