support ros2 action type <action name>. (#894)

* support `ros2 action type <action name>`.

Signed-off-by: Tomoya.Fujita <[email protected]>

* add review comments.

Signed-off-by: Tomoya Fujita <[email protected]>

---------

Signed-off-by: Tomoya.Fujita <[email protected]>
Signed-off-by: Tomoya Fujita <[email protected]>

ros2action/ros2action/verb/type.py

@@ -0,0 +1,40 @@
+# Copyright 2024 Sony Group Corporation.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from ros2action.api import action_name_completer
+from ros2action.api import get_action_names_and_types
+from ros2action.verb import VerbExtension
+from ros2cli.node.strategy import NodeStrategy
+
+
+class TypeVerb(VerbExtension):
+    """Print a action's type."""
+
+    def add_arguments(self, parser, cli_name):
+        arg = parser.add_argument(
+            'action_name',
+            help="Name of the ROS action to get info (e.g. '/fibonacci')")
+        arg.completer = action_name_completer
+
+    def main(self, *, args):
+        with NodeStrategy(args) as node:
+            action_names_and_types = get_action_names_and_types(node=node)
+
+        for (action_name, action_types) in action_names_and_types:
+            if args.action_name == action_name:
+                for action_type in action_types:
+                    print(action_type)
+                return 0
+
+        return 1

ros2action/setup.py

@@ -40,10 +40,10 @@
             'ros2action.verb = ros2action.verb:VerbExtension',
         ],
         'ros2action.verb': [
-            # 'echo = ros2action.verb.echo:EchoVerb',
             'info = ros2action.verb.info:InfoVerb',
             'list = ros2action.verb.list:ListVerb',
             'send_goal = ros2action.verb.send_goal:SendGoalVerb',
+            'type = ros2action.verb.type:TypeVerb',
         ],
     }
 )

ros2action/test/test_cli.py

@@ -221,6 +221,16 @@ def test_list_count(self):
         assert len(command_output_lines) == 1
         assert int(command_output_lines[0]) == 1
 
+    @launch_testing.markers.retry_on_failure(times=5, delay=1)
+    def test_type(self):
+        with self.launch_action_command(arguments=['type', '/fibonacci']) as action_command:
+            assert action_command.wait_for_shutdown(timeout=10)
+        assert action_command.exit_code == launch_testing.asserts.EXIT_OK
+        assert launch_testing.tools.expect_output(
+            expected_lines=['test_msgs/action/Fibonacci'],
+            text=action_command.output, strict=True
+        )
+
     @launch_testing.markers.retry_on_failure(times=5, delay=1)
     def test_send_fibonacci_goal(self):
         with self.launch_action_command(