Add error handling for pending requests in UASocketProtocol

This commit enhances the UASocketProtocol class by introducing a new method, _fail_all_pending, which fails all pending request futures with the given exception. The error handling in the data parsing and request sending methods has been updated to call this new method when exceptions occur, ensuring that pending requests are properly managed in case of errors.

asyncua/client/ua_client.py

@@ -115,10 +115,12 @@ class UASocketProtocol(asyncio.Protocol):
                 data = bytes(buf)
             except ua.UaStatusCodeError as e:
                 self.logger.error("Got error status from server: {}".format(e))
+                self._fail_all_pending(e)
                 self.disconnect_socket()
                 return
-            except Exception:
+            except Exception as e:
                 self.logger.exception("Exception raised while parsing message from server")
+                self._fail_all_pending(e)
                 self.disconnect_socket()
                 return
 
@@ -183,6 +185,8 @@ class UASocketProtocol(asyncio.Protocol):
         try:
             data = await wait_for(self._send_request(request, timeout, message_type), timeout if timeout else None)
         except Exception as ex:
+            if isinstance(ex, ua.UaStatusCodeError):
+                raise
             if self.state != self.OPEN:
                 raise ConnectionError("Connection is closed") from None
             raise UaError("Failed to send request to OPC UA server") from ex
@@ -204,6 +208,13 @@ class UASocketProtocol(asyncio.Protocol):
             return False
         return True
 
+    def _fail_all_pending(self, exc: Exception) -> None:
+        """Fail all pending request futures with the given exception."""
+        for fut in self._callbackmap.values():
+            if not fut.done():
+                fut.set_exception(exc)
+        self._callbackmap.clear()
+
     def _call_callback(self, request_id, body):
         try:
             self._callbackmap[request_id].set_result(body)