bitbake: hashserv: Add websocket connection implementation

Adds support to the hash equivalence client and server to communicate
over websockets. Since websockets are message orientated instead of
stream orientated, and new connection class is needed to handle them.

Note that websocket support does require the 3rd party websockets python
module be installed on the host, but it should not be required unless
websockets are actually being used.

(Bitbake rev: 56dd2fdbfb6350a9eef43a12aa529c8637887a7e)

Signed-off-by: Joshua Watt <JPEWhacker@gmail.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

bitbake/lib/bb/asyncrpc/client.py

@@ -10,7 +10,7 @@ import json
 import os
 import socket
 import sys
-from .connection import StreamConnection, DEFAULT_MAX_CHUNK
+from .connection import StreamConnection, WebsocketConnection, DEFAULT_MAX_CHUNK
 from .exceptions import ConnectionClosedError
 
 
@@ -47,6 +47,15 @@ class AsyncClient(object):
 
         self._connect_sock = connect_sock
 
+    async def connect_websocket(self, uri):
+        import websockets
+
+        async def connect_sock():
+            websocket = await websockets.connect(uri, ping_interval=None)
+            return WebsocketConnection(websocket, self.timeout)
+
+        self._connect_sock = connect_sock
+
     async def setup_connection(self):
         # Send headers
         await self.socket.send("%s %s" % (self.proto_name, self.proto_version))