bitbake: asyncrpc: Add ping method

This method is needed to support startup of the prservice. As it is so
generic we can add it to the common asyncrpc module.

(Bitbake rev: 25ccd697ea76f66b813be2296866b2d3405b079c)

Signed-off-by: Paul Barker <pbarker@konsulko.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

bitbake/lib/bb/asyncrpc/client.py

@@ -103,13 +103,18 @@ class AsyncClient(object):
 
         return await self._send_wrapper(proc)
 
+    async def ping(self):
+        return await self.send_message(
+            {'ping': {}}
+        )
+
 
 class Client(object):
     def __init__(self):
         self.client = self._get_async_client()
         self.loop = asyncio.new_event_loop()
 
-        self._add_methods('connect_tcp', 'close')
+        self._add_methods('connect_tcp', 'close', 'ping')
 
     @abc.abstractmethod
     def _get_async_client(self):

bitbake/lib/bb/asyncrpc/serv.py

@@ -28,6 +28,7 @@ class AsyncServerConnection(object):
         self.max_chunk = DEFAULT_MAX_CHUNK
         self.handlers = {
             'chunk-stream': self.handle_chunk,
+            'ping': self.handle_ping,
         }
         self.logger = logger
 
@@ -123,6 +124,10 @@ class AsyncServerConnection(object):
 
         await self.dispatch_message(msg)
 
+    async def handle_ping(self, request):
+        response = {'alive': True}
+        self.write_message(response)
+
 
 class AsyncServer(object):
     def __init__(self, logger, loop=None):