async def test_async_state_transit():
"""Test async state transit contextmanager."""
state = AsyncState()
state.set(None)
with state.transit(initial=1, success=2, fail=3):
assert state.get() == 1
assert state.get() == 2
state.set(None)
with suppress(ValueError):
with state.transit(initial=1, success=2, fail=3):
assert state.get() == 1
raise ValueError()
assert state.get() == 3
class Connection(Component, ABC):
"""Abstract definition of a connection."""
connection_id = None # type: PublicId
def __init__(
self,
configuration: ConnectionConfig,
data_dir: str,
identity: Optional[Identity] = None,
crypto_store: Optional[CryptoStore] = None,
restricted_to_protocols: Optional[Set[PublicId]] = None,
excluded_protocols: Optional[Set[PublicId]] = None,
**kwargs: Any,
) -> None:
"""
Initialize the connection.
The configuration must be specified if and only if the following
parameters are None: connection_id, excluded_protocols or restricted_to_protocols.
:param configuration: the connection configuration.
:param data_dir: directory where to put local files.
:param identity: the identity object held by the agent.
:param crypto_store: the crypto store for encrypted communication.
:param restricted_to_protocols: the set of protocols ids of the only supported protocols for this connection.
:param excluded_protocols: the set of protocols ids that we want to exclude for this connection.
"""
enforce(configuration is not None, "The configuration must be provided.")
super().__init__(configuration, **kwargs)
enforce(
super().public_id == self.connection_id,
"Connection ids in configuration and class not matching.",
)
self._state = AsyncState(ConnectionStates.disconnected)
self._identity = identity
self._crypto_store = crypto_store
self._data_dir = data_dir
self._restricted_to_protocols = (
restricted_to_protocols if restricted_to_protocols is not None else set()
)
self._excluded_protocols = (
excluded_protocols if excluded_protocols is not None else set()
)
@property
def loop(self) -> asyncio.AbstractEventLoop:
"""Get the event loop."""
enforce(asyncio.get_event_loop().is_running(), "Event loop is not running.")
return asyncio.get_event_loop()
def _ensure_connected(self) -> None: # pragma: nocover
"""Raise exception if connection is not connected."""
if not self.is_connected:
raise ConnectionError("Connection is not connected! Connect first!")
@staticmethod
def _ensure_valid_envelope_for_external_comms(envelope: "Envelope") -> None:
"""
Ensure the envelope sender and to are valid addresses for agent-to-agent communication.
:param envelope: the envelope
"""
enforce(
not envelope.is_sender_public_id,
f"Sender field of envelope is public id, needs to be address. Found={envelope.sender}",
)
enforce(
not envelope.is_to_public_id,
f"To field of envelope is public id, needs to be address. Found={envelope.to}",
)
@contextmanager
def _connect_context(self) -> Generator:
"""Set state connecting, disconnecteing, dicsconnected during connect method."""
with self._state.transit(
initial=ConnectionStates.connecting,
success=ConnectionStates.connected,
fail=ConnectionStates.disconnected,
):
yield
@property
def address(self) -> "Address": # pragma: nocover
"""Get the address."""
if self._identity is None:
raise ValueError(
"You must provide the identity in order to retrieve the address."
)
return self._identity.address
@property
def crypto_store(self) -> CryptoStore: # pragma: nocover
"""Get the crypto store."""
if self._crypto_store is None:
raise ValueError("CryptoStore not available.")
return self._crypto_store
@property
def has_crypto_store(self) -> bool: # pragma: nocover
"""Check if the connection has the crypto store."""
return self._crypto_store is not None
@property
def data_dir(self) -> str: # pragma: nocover
"""Get the data directory."""
return self._data_dir
@property
def component_type(self) -> ComponentType: # pragma: nocover
"""Get the component type."""
return ComponentType.CONNECTION
@property
def configuration(self) -> ConnectionConfig:
"""Get the connection configuration."""
if self._configuration is None: # pragma: nocover
raise ValueError("Configuration not set.")
return cast(ConnectionConfig, super().configuration)
@property
def restricted_to_protocols(self) -> Set[PublicId]: # pragma: nocover
"""Get the ids of the protocols this connection is restricted to."""
if self._configuration is None:
return self._restricted_to_protocols
return self.configuration.restricted_to_protocols
@property
def excluded_protocols(self) -> Set[PublicId]: # pragma: nocover
"""Get the ids of the excluded protocols for this connection."""
if self._configuration is None:
return self._excluded_protocols
return self.configuration.excluded_protocols
@property
def state(self) -> ConnectionStates:
"""Get the connection status."""
return self._state.get()
@state.setter
def state(self, value: ConnectionStates) -> None:
"""Set the connection status."""
if not isinstance(value, ConnectionStates):
raise ValueError(f"Incorrect state: `{value}`")
self._state.set(value)
@abstractmethod
async def connect(self) -> None:
"""Set up the connection."""
@abstractmethod
async def disconnect(self) -> None:
"""Tear down the connection."""
@abstractmethod
async def send(self, envelope: "Envelope") -> None:
"""
Send an envelope.
:param envelope: the envelope to send.
:return: None
"""
@abstractmethod
async def receive(self, *args: Any, **kwargs: Any) -> Optional["Envelope"]:
"""
Receive an envelope.
:return: the received envelope, or None if an error occurred.
"""
@classmethod
def from_dir(
cls,
directory: str,
identity: Identity,
crypto_store: CryptoStore,
data_dir: str,
**kwargs: Any,
) -> "Connection":
"""
Load the connection from a directory.
:param directory: the directory to the connection package.
:param identity: the identity object.
:param crypto_store: object to access the connection crypto objects.
:param data_dir: the assets directory.
:return: the connection object.
"""
configuration = cast(
ConnectionConfig,
load_component_configuration(ComponentType.CONNECTION, Path(directory)),
)
configuration.directory = Path(directory)
return Connection.from_config(
configuration, identity, crypto_store, data_dir, **kwargs
)
@classmethod
def from_config(
cls,
configuration: ConnectionConfig,
identity: Identity,
crypto_store: CryptoStore,
data_dir: str,
**kwargs: Any,
) -> "Connection":
"""
Load a connection from a configuration.
:param configuration: the connection configuration.
:param identity: the identity object.
:param crypto_store: object to access the connection crypto objects.
:param data_dir: the directory of the AEA project data.
:return: an instance of the concrete connection class.
"""
configuration = cast(ConnectionConfig, configuration)
directory = cast(Path, configuration.directory)
load_aea_package(configuration)
connection_module_path = directory / "connection.py"
if not (connection_module_path.exists() and connection_module_path.is_file()):
raise AEAComponentLoadException(
"Connection module '{}' not found.".format(connection_module_path)
)
connection_module = load_module(
"connection_module", directory / "connection.py"
)
classes = inspect.getmembers(connection_module, inspect.isclass)
connection_class_name = cast(str, configuration.class_name)
connection_classes = list(
filter(lambda x: re.match(connection_class_name, x[0]), classes)
)
name_to_class = dict(connection_classes)
logger = get_logger(__name__, identity.name)
logger.debug("Processing connection {}".format(connection_class_name))
connection_class = name_to_class.get(connection_class_name, None)
if connection_class is None:
raise AEAComponentLoadException(
"Connection class '{}' not found.".format(connection_class_name)
)
try:
connection = connection_class(
configuration=configuration,
data_dir=data_dir,
identity=identity,
crypto_store=crypto_store,
**kwargs,
)
except Exception as e: # pragma: nocover # pylint: disable=broad-except
e_str = parse_exception(e)
raise AEAInstantiationException(
f"An error occured during instantiation of connection {configuration.public_id}/{configuration.class_name}:\n{e_str}"
)
return connection
@property
def is_connected(self) -> bool: # pragma: nocover
"""Return is connected state."""
return self.state == ConnectionStates.connected
@property
def is_connecting(self) -> bool: # pragma: nocover
"""Return is connecting state."""
return self.state == ConnectionStates.connecting
@property
def is_disconnected(self) -> bool: # pragma: nocover
"""Return is disconnected state."""
return self.state == ConnectionStates.disconnected