[ros2component] Stop the standalone container when load fails (#269)

* Stop the standalone container when load fails

This prevents zombie container processes from hanging around when a
component fails to load.

Closes: #260

Signed-off-by: Michael Carroll <[email protected]>

Author: mjcarroll

ros2component/ros2component/verb/standalone.py

@@ -12,6 +12,8 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+import platform
+import signal
 import uuid
 
 from ros2cli.node.direct import DirectNode
@@ -39,13 +41,21 @@ def main(self, *, args):
         container = run_standalone_container(container_node_name=args.container_node_name)
 
         with DirectNode(args) as node:
-            load_component_into_container(
-                node=node, remote_container_node_name=args.container_node_name,
-                package_name=args.package_name, plugin_name=args.plugin_name,
-                node_name=args.node_name, node_namespace=args.node_namespace,
-                log_level=args.log_level, remap_rules=args.remap_rules,
-                parameters=args.parameters, extra_arguments=args.extra_arguments
-            )
+            try:
+                load_component_into_container(
+                    node=node, remote_container_node_name=args.container_node_name,
+                    package_name=args.package_name, plugin_name=args.plugin_name,
+                    node_name=args.node_name, node_namespace=args.node_namespace,
+                    log_level=args.log_level, remap_rules=args.remap_rules,
+                    parameters=args.parameters, extra_arguments=args.extra_arguments
+                )
+            except RuntimeError as ex:
+                # In case the component fails to load, kill the container.
+                print('{}, interrupting container node'.format(ex))
+                if platform.system() == 'Windows':
+                    container.send_signal(signal.CTRL_C_EVENT)
+                else:
+                    container.send_signal(signal.SIGINT)
 
         while container.returncode is None:
             try: