def __init__(self, session=None, connection_factory=None, resource_factory=None, collection_factory=None): """ Creates a ``Session`` instance. :param session: (Optional) Custom instantiated ``botocore`` instance. Useful if you have specific needs. If not present, a default ``Session`` will be created. :type session: <botocore.session.Session> instance :param connection_factory: (Optional) Specifies a custom ``ConnectionFactory`` to be used. Useful if you need to change how ``Connection`` objects are constructed by the session. :type connection_factory: <boto3.core.connection.ConnectionFactory> instance :param resource_factory: (Optional) Specifies a custom ``ResourceFactory`` to be used. Useful if you need to change how ``Resource`` objects are constructed by the session. :type resource_factory: <boto3.core.resources.ResourceFactory> instance :param collection_factory: (Optional) Specifies a custom ``CollectionFactory`` to be used. Useful if you need to change how ``Collection`` objects are constructed by the session. :type collection_factory: <boto3.core.collections.CollectionFactory> instance """ super(Session, self).__init__() self.core_session = session self.connection_factory = connection_factory self.resource_factory = resource_factory self.collection_factory = collection_factory self.cache = self.cache_class() if not self.core_session: self.core_session = botocore.session.get_session() self.core_session.user_agent_name = USER_AGENT_NAME self.core_session.user_agent_version = USER_AGENT_VERSION if not self.connection_factory: from boto3.core.connection import ConnectionFactory self.connection_factory = ConnectionFactory(session=self) if not self.resource_factory: from boto3.core.resources import ResourceFactory self.resource_factory = ResourceFactory(session=self) if not self.collection_factory: from boto3.core.collections import CollectionFactory self.collection_factory = CollectionFactory(session=self)
class Session(object): """ Stores all the state for a given ``boto3`` session. Can dynamically create all the various ``Connection`` classes. Usage:: >>> from boto3.core.session import Session >>> session = Session() >>> sqs_conn = session.connect_to('sqs', region_name='us-west-2') """ cache_class = ServiceCache def __init__(self, session=None, connection_factory=None, resource_factory=None, collection_factory=None): """ Creates a ``Session`` instance. :param session: (Optional) Custom instantiated ``botocore`` instance. Useful if you have specific needs. If not present, a default ``Session`` will be created. :type session: <botocore.session.Session> instance :param connection_factory: (Optional) Specifies a custom ``ConnectionFactory`` to be used. Useful if you need to change how ``Connection`` objects are constructed by the session. :type connection_factory: <boto3.core.connection.ConnectionFactory> instance :param resource_factory: (Optional) Specifies a custom ``ResourceFactory`` to be used. Useful if you need to change how ``Resource`` objects are constructed by the session. :type resource_factory: <boto3.core.resources.ResourceFactory> instance :param collection_factory: (Optional) Specifies a custom ``CollectionFactory`` to be used. Useful if you need to change how ``Collection`` objects are constructed by the session. :type collection_factory: <boto3.core.collections.CollectionFactory> instance """ super(Session, self).__init__() self.core_session = session self.connection_factory = connection_factory self.resource_factory = resource_factory self.collection_factory = collection_factory self.cache = self.cache_class() if not self.core_session: self.core_session = botocore.session.get_session() self.core_session.user_agent_name = USER_AGENT_NAME self.core_session.user_agent_version = USER_AGENT_VERSION if not self.connection_factory: from boto3.core.connection import ConnectionFactory self.connection_factory = ConnectionFactory(session=self) if not self.resource_factory: from boto3.core.resources import ResourceFactory self.resource_factory = ResourceFactory(session=self) if not self.collection_factory: from boto3.core.collections import CollectionFactory self.collection_factory = CollectionFactory(session=self) def get_connection(self, service_name): """ Returns a ``Connection`` **class** for a given service. :param service_name: A string that specifies the name of the desired service. Ex. ``sqs``, ``sns``, ``dynamodb``, etc. :type service_name: string :rtype: <boto3.core.connection.Connection subclass> """ try: return self.cache.get_connection(service_name) except NotCached: pass # We didn't find it. Construct it. new_class = self.connection_factory.construct_for(service_name) self.cache.set_connection(service_name, new_class) return new_class def get_resource(self, service_name, resource_name, base_class=None): """ Returns a ``Resource`` **class** for a given service. :param service_name: A string that specifies the name of the desired service. Ex. ``sqs``, ``sns``, ``dynamodb``, etc. :type service_name: string :param resource_name: A string that specifies the name of the desired class. Ex. ``Queue``, ``Notification``, ``Table``, etc. :type resource_name: string :param base_class: (Optional) The base class of the object. Prevents "magically" loading the wrong class (one with a different base). :type base_class: class :rtype: <boto3.core.resources.Resource subclass> """ try: return self.cache.get_resource(service_name, resource_name, base_class=base_class) except NotCached: pass # We didn't find it. Construct it. new_class = self.resource_factory.construct_for(service_name, resource_name, base_class=base_class) self.cache.set_resource(service_name, resource_name, new_class) return new_class def get_collection(self, service_name, collection_name, base_class=None): """ Returns a ``Collection`` **class** for a given service. :param service_name: A string that specifies the name of the desired service. Ex. ``sqs``, ``sns``, ``dynamodb``, etc. :type service_name: string :param collection_name: A string that specifies the name of the desired class. Ex. ``QueueCollection``, ``NotificationCollection``, ``TableCollection``, etc. :type collection_name: string :param base_class: (Optional) The base class of the object. Prevents "magically" loading the wrong class (one with a different base). :type base_class: class :rtype: <boto3.core.collections.Collection subclass> """ try: return self.cache.get_collection(service_name, collection_name, base_class=base_class) except NotCached: pass # We didn't find it. Construct it. new_class = self.collection_factory.construct_for(service_name, collection_name, base_class=base_class) self.cache.set_collection(service_name, collection_name, new_class) return new_class def connect_to(self, service_name, **kwargs): """ Shortcut method to make instantiating the ``Connection`` classes easier. Forwards ``**kwargs`` like region, keys, etc. on to the constructor. :param service_name: A string that specifies the name of the desired service. Ex. ``sqs``, ``sns``, ``dynamodb``, etc. :type service_name: string :rtype: <boto3.core.connection.Connection> instance """ service_class = self.get_connection(service_name) return service_class.connect_to(**kwargs) def get_core_service(self, service_name): """ Returns a ``botocore.service.Service``. Mostly an abstraction for the ``*Connection`` objects to get what they need for introspection. :param service_name: A string that specifies the name of the desired service. Ex. ``sqs``, ``sns``, ``dynamodb``, etc. :type service_name: string :rtype: <botocore.service.Service subclass> """ return self.core_session.get_service(service_name)