Add get_addresses() and get_port() to SSHAcceptor class

This commit adds functions to get listening socket information on
SSH listeners. New method get_addresses() gets a list of all of the
IP addresses and ports being listened on, and get_port() will return
just the listening port, but only when there's a single listening
socket or if all the sockets are listening on the same port. Otherwise,
a value of 0 is returned. Thanks go to Allison Karlitskaya for
suggesting this feature.

asyncssh/connection.py

@@ -693,13 +693,59 @@ async def __aexit__(self, _exc_type: Optional[Type[BaseException]],
     def __getattr__(self, name: str) -> Any:
         return getattr(self._server, name)
 
+    def get_addresses(self) -> List[Tuple]:
+        """Get socket addresses being listened on
+
+           This method returns the IP addresses and ports being
+           listened on. It returns tuples of the form returned by
+           :meth:`socket.getsockname`.  If the listener was created
+           using a hostname, the host's resolved IPs will be returned.
+           If the requested listening port was `0`, the selected
+           listening ports will be returned.
+
+           :returns: A list of IP addresses and ports being listened on
+
+        """
+
+        return [sock.getsockname() for sock in self.sockets]
+
+    def get_port(self) -> int:
+        """Return the port number being listened on
+
+           This method returns the port number this SSHAcceptor is
+           listening on. If it is listening on multiple sockets with
+           different port numbers, this function will return `0`. In
+           this case, :meth:`get_addresses` can be used to retrieve
+           the full list of listening addresses and ports.
+
+           :returns: The port number being listened on
+
+        """
+
+        if hasattr(self._server, 'get_port'):
+            print(type(self._server))
+            return self._server.get_port()
+        else:
+            ports = set(addr[1] for addr in self.get_addresses())
+            return ports.pop() if len(ports) == 1 else 0
+
     def close(self) -> None:
-        """Close this SSH listener"""
+        """Stop listening for new connections
+
+           This method can be called to stop listening for new
+           SSH connections. Existing connections will remain open.
+
+        """
 
         self._server.close()
 
     async def wait_closed(self) -> None:
-        """Wait for this SSH listener to close"""
+        """Wait for this listener to close
+
+           This method is a coroutine which waits for this
+           listener to be closed.
+
+        """
 
         await self._server.wait_closed()
 

docs/api.rst

@@ -1038,9 +1038,13 @@ SSHAcceptor
 
 .. autoclass:: SSHAcceptor()
 
-   ====================== =
+   ============================= =
+   .. automethod:: get_addresses
+   .. automethod:: get_port
+   .. automethod:: close
+   .. automethod:: wait_closed
    .. automethod:: update
-   ====================== =
+   ============================= =
 
 
 SSHListener

tests/test_connection.py

@@ -2276,7 +2276,7 @@ async def test_ssh_listen_context_manager(self):
         """Test using an SSH listener as a context manager"""
 
         async with self.listen() as server:
-            listen_port = server.sockets[0].getsockname()[1]
+            listen_port = server.get_port()
 
 
             async with asyncssh.connect('127.0.0.1', listen_port,