Deal with ParameterUninitializedException for parameter service (#1033)

* Deal with ParameterUninitializedException for parameter service Signed-off-by: Barry Xu <barry.xu@sony.com> * Enable all tests in test_parameter_client.py Signed-off-by: Barry Xu <barry.xu@sony.com> * Get empty value for ParameterUninitializedException Signed-off-by: Barry Xu <barry.xu@sony.com> Signed-off-by: Barry Xu <barry.xu@sony.com>
ros2 · Nov 14, 2022 · e442ad2 · e442ad2
1 parent d2901dd
commit e442ad2
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Showing 3 changed files with 24 additions and 2 deletions.
diff --git a/rclpy/CMakeLists.txt b/rclpy/CMakeLists.txt
@@ -175,6 +175,7 @@ if(BUILD_TESTING)
       test/test_messages.py
       test/test_node.py
       test/test_parameter.py
+      test/test_parameter_client.py
       test/test_publisher.py
       test/test_qos.py
       test/test_qos_event.py

diff --git a/rclpy/rclpy/parameter_service.py b/rclpy/rclpy/parameter_service.py
@@ -17,7 +17,7 @@
 from rcl_interfaces.msg import SetParametersResult
 from rcl_interfaces.srv import DescribeParameters, GetParameters, GetParameterTypes
 from rcl_interfaces.srv import ListParameters, SetParameters, SetParametersAtomically
-from rclpy.exceptions import ParameterNotDeclaredException
+from rclpy.exceptions import ParameterNotDeclaredException, ParameterUninitializedException
 from rclpy.parameter import Parameter, PARAMETER_SEPARATOR_STRING
 from rclpy.qos import qos_profile_parameters
 from rclpy.validate_topic_name import TOPIC_SEPARATOR_STRING
@@ -80,7 +80,7 @@ def _get_parameters_callback(self, request, response):
         for name in request.names:
             try:
                 param = node.get_parameter(name)
-            except ParameterNotDeclaredException:
+            except (ParameterNotDeclaredException, ParameterUninitializedException):
                 response.values = node.get_parameters([])
                 return response
             response.values.append(param.get_parameter_value())

diff --git a/rclpy/test/test_parameter_client.py b/rclpy/test/test_parameter_client.py
@@ -170,3 +170,24 @@ def test_load_parameter_file_atomically(self):
         finally:
             if os.path.exists(f.name):
                 os.unlink(f.name)
+
+    def test_get_uninitialized_parameter(self):
+        self.target_node.declare_parameter('uninitialized_parameter', Parameter.Type.STRING)
+
+        # The type in description should be STRING
+        future = self.client.describe_parameters(['uninitialized_parameter'])
+        self.executor.spin_until_future_complete(future)
+        results = future.result()
+        assert results is not None
+        assert len(results.descriptors) == 1
+        assert results.descriptors[0].type == ParameterType.PARAMETER_STRING
+        assert results.descriptors[0].name == 'uninitialized_parameter'
+
+        # The value should be empty
+        future = self.client.get_parameters(['uninitialized_parameter'])
+        self.executor.spin_until_future_complete(future)
+        results = future.result()
+        assert results is not None
+        assert results.values == []
+
+        self.target_node.undeclare_parameter('uninitialized_parameter')