translator from LaunchConfiguration to YML

src/rosdiscover/ros2_translator/arch.py

@@ -0,0 +1,52 @@
+import json
+import argparse
+from launch.actions import IncludeLaunchDescription
+from launch_ros.actions import Node
+from launch.launch_description_sources import get_launch_description_from_python_launch_file
+
+
+def toyaml(nodes):
+    to_yaml = {}
+    no_name = 0
+    for node in nodes:
+        if isinstance(node, IncludeLaunchDescription):
+            description_from_node = node._IncludeLaunchDescription__launch_description_source.try_get_launch_description_without_context()
+            if description_from_node is None:
+                continue
+            nodes1 = description_from_node.entities
+            to_yaml.update(toyaml(nodes1))
+        if isinstance(node, Node):
+            # Note: The code directly accesses variables since there are no getters for
+            # these specific variables in launch.
+            # This code might break with changed implementations of launch
+            dic = {}
+            if node._Node__node_name:
+                name_entry = node._Node__node_name
+                dic['name'] = node._Node__node_name
+            else:
+                name_entry = 'unknown' + str(no_name)
+                no_name += 1
+                dic['name'] = name_entry
+            if node._Node__node_namespace:
+                dic['namespace'] = node._Node__node_namespace
+            if node._Node__node_executable:
+                dic['executable'] = node._Node__node_executable
+            if node._Node__package:
+                dic['package'] = node._Node__package
+            to_yaml[name_entry] = dic
+    return to_yaml
+
+
+if __name__ == '__main__':
+    parser = argparse.ArgumentParser(description='Find nodes')
+    parser.add_argument('launchfile', type=str)
+    parser.add_argument('--output', type=str)
+    args = parser.parse_args()
+    if args.output:
+        yaml_file = args.output
+    else:
+        yaml_file = 'arch.yml'
+    description = get_launch_description_from_python_launch_file(args.launchfile)
+    nodes = description.entities
+    with open(yaml_file, 'w') as f:
+        f.write(json.dumps(toyaml(nodes), indent=4, separators=(". ", " = ")))