rosbag message headers missing dependency information from rosjava

[jacknlliu]

We record the topics from rosjava using rosbag

rosbag record -O test.bag '/iiwa/joint_states'

Then we use rostopic to convert the bag to csv file

rostopic echo -b test.bag -p '/iiwa/joint_states' > joint_states.txt 

But we get the following errors:

Traceback (most recent call last):
  File "/opt/ros/kinetic/bin/rostopic", line 35, in <module>
    rostopic.rostopicmain()
  File "/opt/ros/kinetic/lib/python2.7/dist-packages/rostopic/__init__.py", line 2093, in rostopicmain
    _rostopic_cmd_echo(argv)
  File "/opt/ros/kinetic/lib/python2.7/dist-packages/rostopic/__init__.py", line 1392, in _rostopic_cmd_echo
    _rostopic_echo(topic, callback_echo, bag_file=options.bag)
  File "/opt/ros/kinetic/lib/python2.7/dist-packages/rostopic/__init__.py", line 1013, in _rostopic_echo
    _rostopic_echo_bag(callback_echo, bag_file)
  File "/opt/ros/kinetic/lib/python2.7/dist-packages/rostopic/__init__.py", line 991, in _rostopic_echo_bag
    for t, msg, timestamp in b.read_messages():
  File "/opt/ros/kinetic/lib/python2.7/dist-packages/rosbag/bag.py", line 2337, in read_messages
    yield self.seek_and_read_message_data_record((entry.chunk_pos, entry.offset), raw)
  File "/opt/ros/kinetic/lib/python2.7/dist-packages/rosbag/bag.py", line 2475, in seek_and_read_message_data_record
    msg_type = _get_message_type(connection_info)
  File "/opt/ros/kinetic/lib/python2.7/dist-packages/rosbag/bag.py", line 1571, in _get_message_type
    message_type = genpy.dynamic.generate_dynamic(info.datatype, info.msg_def)[info.datatype]
  File "/opt/ros/kinetic/lib/python2.7/dist-packages/genpy/dynamic.py", line 155, in generate_dynamic
    for l in msg_generator(msg_context, spec, search_path):
  File "/opt/ros/kinetic/lib/python2.7/dist-packages/genpy/generator.py", line 741, in msg_generator
    genmsg.msg_loader.load_depends(msg_context, spec, search_path)
  File "/opt/ros/kinetic/lib/python2.7/dist-packages/genmsg/msg_loader.py", line 349, in load_depends
    return load_msg_depends(msg_context, spec, msg_search_path)
  File "/opt/ros/kinetic/lib/python2.7/dist-packages/genmsg/msg_loader.py", line 318, in load_msg_depends
    depspec = load_msg_by_type(msg_context, resolved_type, search_path)
  File "/opt/ros/kinetic/lib/python2.7/dist-packages/genmsg/msg_loader.py", line 124, in load_msg_by_type
    file_path = get_msg_file(package_name, base_type, search_path)
  File "/opt/ros/kinetic/lib/python2.7/dist-packages/genmsg/msg_loader.py", line 83, in get_msg_file
    % (base_type, package, search_path), base_type, package, search_path)
genmsg.msg_loader.MsgNotFound: Cannot locate message [Header]: unknown package [std_msgs] on search path [{}]

It looks like rosjava is not publishing the full message definition correctly.

rostopic echo -b test.bag ...

The rostopic echo -b can't solve the dynamic message types.

And if we play the bag file, and then using rostopic echo to save the topic, it works.

rosbag play test.bag

rostopic echo -p '/iiwa/joint_states' > joint_states.txt

A workaround, please see rosbag_fixer, and we can use this python script to convert the rosbag to a normal rosbag file.

system information:
Ubuntu 16.04 
ROS kinetic
ros bag: 1.12.12-0xenial-20171116-225733-0800
rostopic: 1.12.12-0xenial-20171116-231053-0800

Reference

• rosbag_fixer
• Message Headers missing dependency information
• IMU messages cannot be converted to csv from bag file
• cannot convert imu messages from bagfile to csv file
• Error when extracting topic of type sensor_msgs/Imu