If updating remote fails, reflect the failure locally

src/rqt_reconfigure/param_api.py

@@ -130,7 +130,7 @@ def _call_service(self, client, request, timeout=1.0):
         if result is None:
             raise AsyncServiceCallFailed(hint='the target node may not be spinning')
 
-        return future.result()
+        return result
 
 
 def create_param_client(node, remote_node_name, param_change_callback=None):

src/rqt_reconfigure/param_editors.py

@@ -71,9 +71,15 @@ def __init__(self, param_client, parameter, descriptor):
     def update_remote(self, value):
         # Update the value on Parameter Server.
         try:
-            self._param_client.set_parameters([self.parameter])
+            result = self._param_client.set_parameters([self.parameter])
+            for res in result.results:
+                if not res.successful:
+                    logging.warn('Failed to set parameters for node: ' + res.reason)
+                    return False
         except Exception as e:
             logging.warn('Failed to set parameters for node: ' + str(e))
+            return False
+        return True
 
     def update_local(self, value):
         """
@@ -95,7 +101,8 @@ def update(self, value):
         old_value = self.parameter.value
         self.update_local(value)
         if self.parameter.value != old_value:
-            self.update_remote(value)
+            if not self.update_remote(value):
+                self.update_local(old_value)
 
     def display(self, grid):
         """