DOCS: object detection usecase

utils/ros2_topic_to_json.py

@@ -0,0 +1,72 @@
+"""
+  ROS2_Topic_to_json
+  ROS 2 program for outputting system objects to json format
+
+  From https://github.com/ros2/ros2cli/blob/humble/ros2topic/ros2topic/verb/list.py
+
+  @shalenikol release 0.1
+"""
+"""
+usage: python ros2_topic_to_json.py [-h] [--jsonpath JSONPATH]
+
+options:
+  -h, --help           show this help message and exit
+  --jsonpath JSONPATH  Output file in json-format
+"""
+import argparse
+import json
+from ros2cli.node.strategy import NodeStrategy
+from ros2topic.api import get_topic_names_and_types
+
+OUTPUT_FILE = "topics.json"
+
+# def show_topic_info(topic_info, is_publisher):
+#     message = ('Published' if is_publisher else 'Subscribed') + ' topics:\n'
+#     for (topic_name, topic_types, pub_count, sub_count) in topic_info:
+#         count = pub_count if is_publisher else sub_count
+#         if count:
+#             topic_types_formatted = ', '.join(topic_types)
+#             count_str = str(count) + ' ' + ('publisher' if is_publisher else 'subscriber') \
+#                 + ('s' if count > 1 else '')
+#             message += f' * {topic_name} [{topic_types_formatted}] {count_str}\n'
+#     return message
+
+def main(args, jsonpath):
+    topic_info = []
+    with NodeStrategy(args) as node:
+        topic_names_and_types = get_topic_names_and_types(
+            node=node,
+            include_hidden_topics=False)
+        for (topic_name, topic_types) in topic_names_and_types:
+            # if args.verbose:
+            #     pub_count = node.count_publishers(topic_name)
+            #     sub_count = node.count_subscribers(topic_name)
+            #     topic_info.append((topic_name, topic_types, pub_count, sub_count))
+            # else:
+                topic_info.append((topic_name, topic_types))
+
+    # if args.count_topics:
+        print(f"---> number of topics: {len(topic_names_and_types)}")
+
+        j_data = {"topics": topic_info}
+        with open(jsonpath, "w") as fh:
+            json.dump(j_data, fh, indent=2)
+    # elif topic_names_and_types:
+    #     if args.verbose:
+    #         print(show_topic_info(topic_info, is_publisher=True))
+    #         print(show_topic_info(topic_info, is_publisher=False))
+        # else:
+        for (topic_name, topic_types) in topic_info:
+            msg = "{topic_name}"
+            # topic_types_formatted = ', '.join(topic_types)
+            # if args.show_types:
+            #     msg += ' [{topic_types_formatted}]'
+            print(msg.format_map(locals()))
+
+if __name__ == "__main__":
+    parser = argparse.ArgumentParser()
+    parser.add_argument("--jsonpath", default=OUTPUT_FILE, help="Output file in json-format")
+    m_args = parser.parse_args()
+
+    args = {}
+    main(args, m_args.jsonpath)