feat(port=0): Add infrastructure to handle dynamically assigned port

python/src/wslink/backends/aiohttp/__init__.py

@@ -80,7 +80,10 @@ def get_config(self):
     def set_config(self, config):
         self.config = config
 
-    async def start(self):
+    def get_port(self):
+        return self.app["state"]["runner"].addresses[0][1]
+
+    async def start(self, port_callback=None):
         app = self.app
         server_config = self.config
         host = self.config["host"]
@@ -103,6 +106,9 @@ async def start(self):
         logging.info("awaiting site startup")
         await my_site.start()
 
+        if port_callback is not None:
+            port_callback(self.get_port())
+
         logging.info("awaiting running future")
         await running
 
@@ -418,7 +424,7 @@ async def sendWrappedMessage(self, rpcid, content, method="", client_id=None):
             return
 
         websockets = (
-            [self.connections[client_id]]
+            [self.connections.get(client_id)]
             if client_id
             else [self.connections[c] for c in self.connections]
         )
@@ -458,7 +464,8 @@ async def sendWrappedMessage(self, rpcid, content, method="", client_id=None):
                 pub.publishManager.unregisterAttachment(key)
 
         for ws in websockets:
-            await ws.send_str(encMsg)
+            if ws is not None:
+                await ws.send_str(encMsg)
 
         loop = asyncio.get_running_loop()
         loop.call_soon(pub.publishManager.freeAttachments, found_keys)

python/src/wslink/server.py

@@ -129,7 +129,16 @@ def start(argv=None, protocol=wsl.ServerProtocol, description="wslink web-server
 # =============================================================================
 def stop_webserver():
     if ws_server:
-        ws_server.stop()
+        loop = asyncio.get_event_loop()
+        return loop.create_task(ws_server.stop())
+
+# =============================================================================
+# Get webserver port (useful when 0 is provided and a dynamic one was picked)
+# =============================================================================
+def get_port():
+    if ws_server:
+        return ws_server.get_port()
+    return -1
 
 
 # =============================================================================
@@ -218,8 +227,12 @@ def start_webserver(
     # Until then, we can start the server this way
     loop = asyncio.get_event_loop()
 
+    port_callback = None
+    if hasattr(wslinkServer, "port_callback"):
+        port_callback = wslinkServer.port_callback
+
     try:
-        loop.run_until_complete(ws_server.start())
+        loop.run_until_complete(ws_server.start(port_callback))
     finally:
         loop.close()