Source code for distributed.comm.registry

from abc import ABC, abstractmethod


[docs]class Backend(ABC): """ A communication backend, selected by a given URI scheme (e.g. 'tcp'). """ # I/O
[docs] @abstractmethod def get_connector(self): """ Get a connector object usable for connecting to addresses. """
[docs] @abstractmethod def get_listener(self, loc, handle_comm, deserialize, **connection_args): """ Get a listener object for the scheme-less address *loc*. """
# Address handling
[docs] @abstractmethod def get_address_host(self, loc): """ Get a host name (normally an IP address) identifying the host the address is located on. *loc* is a scheme-less address. """
[docs] @abstractmethod def resolve_address(self, loc): """ Resolve the address into a canonical form. *loc* is a scheme-less address. Simple implementations may return *loc* unchanged. """
[docs] def get_address_host_port(self, loc): """ Get the (host, port) tuple of the scheme-less address *loc*. This should only be implemented by IP-based transports. """ raise NotImplementedError
[docs] @abstractmethod def get_local_address_for(self, loc): """ Get the local listening address suitable for reaching *loc*. """
# The {scheme: Backend} mapping backends = {} def get_backend(scheme: str, require: bool = True) -> Backend: """ Get the Backend instance for the given *scheme*. It looks for matching scheme in dask's internal cache, and falls-back to package metadata for the group name ``distributed.comm.backends`` Parameters ---------- require : bool Verify that the backends requirements are properly installed. See https://setuptools.readthedocs.io/en/latest/pkg_resources.html for more information. """ backend = backends.get(scheme) if backend is None: import pkg_resources backend = None for backend_class_ep in pkg_resources.iter_entry_points( "distributed.comm.backends", scheme ): # resolve and require are equivalent to load backend_factory = backend_class_ep.resolve() if require: backend_class_ep.require() backend = backend_factory() if backend is None: raise ValueError( "unknown address scheme %r (known schemes: %s)" % (scheme, sorted(backends)) ) else: backends[scheme] = backend return backend