Expose Python code generation via rosidl generate CLI

rosidl_generator_py/bin/rosidl_generator_py

@@ -33,8 +33,8 @@ def main(argv=sys.argv[1:]):
         help='All the available typesupport implementations')
     args = parser.parse_args(argv)
 
-    return generate_py(args.generator_arguments_file, args.typesupport_impls.split(';'))
-
+    generate_py(args.generator_arguments_file, args.typesupport_impls.split(';'))
+    return 0
 
 if __name__ == '__main__':
     sys.exit(main())

rosidl_generator_py/package.xml

@@ -25,7 +25,9 @@
   <buildtool_export_depend>rosidl_typesupport_c</buildtool_export_depend>
   <buildtool_export_depend>rosidl_typesupport_interface</buildtool_export_depend>
 
+  <exec_depend>ament_index_python</exec_depend>
   <exec_depend>python3-numpy</exec_depend>
+  <exec_depend>rosidl_cli</exec_depend>
   <exec_depend>rosidl_generator_c</exec_depend>
   <exec_depend>rosidl_parser</exec_depend>
   <exec_depend>rosidl_runtime_c</exec_depend>

rosidl_generator_py/rosidl_generator_py/cli.py

@@ -0,0 +1,71 @@
+# Copyright 2021 Open Source Robotics Foundation, Inc.
+#
+# 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.
+
+import pathlib
+
+from ament_index_python import get_package_share_directory
+from ament_index_python import get_resources
+
+from rosidl_cli.command.generate.extensions import GenerateCommandExtension
+from rosidl_cli.command.helpers import legacy_generator_arguments_file
+from rosidl_cli.command.translate.api import translate
+
+from rosidl_generator_py import generate_py
+
+
+class GeneratePython(GenerateCommandExtension):
+
+    def generate(
+        self,
+        package_name,
+        interface_files,
+        include_paths,
+        output_path
+    ):
+        package_share_path = \
+            pathlib.Path(get_package_share_directory('rosidl_generator_py'))
+        templates_path = package_share_path / 'resource'
+
+        # Normalize interface definition format to .idl
+        idl_interface_files = []
+        non_idl_interface_files = []
+        for path in interface_files:
+            if not path.endswith('.idl'):
+                non_idl_interface_files.append(path)
+            else:
+                idl_interface_files.append(path)
+        if non_idl_interface_files:
+            idl_interface_files.extend(translate(
+                package_name=package_name,
+                interface_files=non_idl_interface_files,
+                include_paths=include_paths,
+                output_format='idl',
+                output_path=output_path / 'tmp',
+            ))
+
+        # Generate code
+        typesupport_implementations = ['rosidl_typesupport_c']
+        typesupport_implementations.extend(
+            get_resources('rosidl_typesupport_c')
+        )
+        with legacy_generator_arguments_file(
+            package_name=package_name,
+            interface_files=idl_interface_files,
+            include_paths=include_paths,
+            templates_path=templates_path,
+            output_path=output_path
+        ) as path_to_arguments_file:
+            return generate_py(
+                path_to_arguments_file,
+                typesupport_implementations)

rosidl_generator_py/rosidl_generator_py/generate_py_impl.py

@@ -58,7 +58,7 @@ def generate_py(generator_arguments_file, typesupport_impls):
         '_idl.py.em': '_%s.py',
         '_idl_support.c.em': '_%s_s.c',
     }
-    generate_files(generator_arguments_file, mapping)
+    generated_files = generate_files(generator_arguments_file, mapping)
 
     args = read_generator_arguments(generator_arguments_file)
     package_name = args['package_name']
@@ -157,8 +157,9 @@ def print_warning_if_reserved_keyword(member_name, interface_type, interface_nam
             expand_template(
                 template_file, data, generated_file,
                 minimum_timestamp=latest_target_timestamp)
+            generated_files.append(generated_file)
 
-    return 0
+    return generated_files
 
 
 def value_to_py(type_, value, array_as_tuple=False):

rosidl_generator_py/setup.cfg

@@ -0,0 +1,3 @@
+[options.entry_points]
+rosidl_cli.command.generate.type_extensions =
+  py = rosidl_generator_py.cli:GeneratePython