ros2 / ros2/ros2cli

Cannot/don't know how to publish message with `byte[]` field

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bug help wanted
Dominant language
Python
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262
Forks
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Avg merge
23h 15m
Merged PRs (30d)
12

Description

Bug report

Required Info:

  • Operating System:
    • Ubuntu 20.04
  • Installation type:
    • binaries
  • Version or commit hash:
    • ros2cli 0.13.4
  • DDS implementation:
    • rmw_cyclonedds_cpp: 0.22.5
  • Client library (if applicable):
    • N/A
Steps to reproduce issue

Trying to ros2 topic pub a std_msgs/msg/ByteMultiArray message. I have tried:

bash ros2 topic pub -1 /whatever std_msgs/msg/ByteMultiArray "{data: [{3}, {4}]}"

and

bash ros2 topic pub -1 /whatever std_msgs/msg/ByteMultiArray "{data: [0x03, 0x04]}" 
Expected behavior

Successful publishing.

Actual behavior

Error response:

Failed to populate field: The 'data' field must be a set or sequence and each value of type 'bytes'
Additional information

Contributor guide

Open the contributing guide

First steps

  1. Read the whole issue, then the project's contributing guide.
  2. Comment on the issue to say you are picking it up — it saves two people doing the same work.
  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

Research direction

Start with the ros2 topic pub entry point and reproduce the std_msgs/msg/ByteMultiArray command using the examples in the issue. Trace how the CLI populates the data field and verify that a byte sequence such as [0x03, 0x04] publishes successfully without the reported type error.

Written by the indexing model from the issue text.

Assessment

Tech stack
python, shell
Domain
cli
Issue type
Bug
Difficulty
3/5
Estimated time
1-2 days
Activity status
Stale
Clarity
Mostly clear
Newbie friendliness
45/100

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