roslibpy 2.1.0

Python ROS Bridge library.

Python ROS Bridge library allows to use Python and IronPython to interact with ROS, the open-source robotic middleware. It uses WebSockets to connect to rosbridge 2.0 and provides publishing, subscribing, service calls, actionlib, TF, and other essential ROS functionality.

Unlike the rospy library, this does not require a local ROS environment, allowing usage from platforms other than Linux.

The API of roslibpy is modeled to closely match that of roslibjs.

ROS 1 is fully supported. ROS 2 support is still in progress.

Main features

• Topic publishing and subscribing.

• Service calls (client).

• Service advertisement (server).

• ROS parameter management (get/set/delete).

• ROS API services for getting ROS meta-information.

• Actionlib support for interfacing with preemptable tasks.

• TF Client via the tf2_web_republisher.

Roslibpy runs on Python 3.x and IronPython 2.7.

Installation

To install roslibpy, simply use pip:

pip install roslibpy

The default WebSocket transport on CPython uses Autobahn on the Twisted reactor. An alternative transport that runs the same Autobahn WebSocket stack on an asyncio event loop is also available (no extra dependencies required); see Transport selection below.

For IronPython, the pip command is slightly different:

ipy -X:Frames -m pip install --user roslibpy

Remember that you will need a working ROS setup including the rosbridge server and TF2 web republisher accessible within your network.

Transport selection

CPython uses the twisted transport by default; IronPython uses cli. The asyncio transport runs the same Autobahn WebSocket stack on an asyncio event loop. To select it, either pass it per client, set the process-wide default, or set the environment variable:

roslibpy.Ros(host='localhost', port=9090, transport='asyncio')
roslibpy.set_default_transport('asyncio')
ROSLIBPY_TRANSPORT=asyncio python my_script.py

Documentation

The full documentation, including examples and API reference is available on readthedocs.

Contributing

Make sure you setup your local development environment correctly:

• Clone the roslibpy repository.

• Create a virtual environment.

• Install development dependencies:

pip install -r requirements-dev.txt

You’re ready to start coding!

During development, use pyinvoke tasks on the command prompt to ease recurring operations:

• invoke clean: Clean all generated artifacts.

• invoke check: Run various code and documentation style checks.

• invoke docs: Generate documentation.

• invoke test: Run all tests and checks in one swift command.

• invoke: Show available tasks.

For more details, check the Contributor’s Guide available as part of the documentation.

The default branch was recently renamed to main. If you’ve already cloned this repository, you’ll need to update your local repository structure with the following lines:

git branch -m master main
git fetch origin
git branch -u origin/main main

Releasing this project

Ready to release a new version roslibpy? Here’s how to do it:

• We use semver, i.e. we bump versions as follows:

  • patch: bugfixes.

  • minor: backwards-compatible features added.

  • major: backwards-incompatible changes.

• Update the CHANGELOG.rst with all novelty!

• Create a release branch and prepare the release:

git checkout -b release-x.y.z
invoke release [patch|minor|major]

• This will run tests, bump the version, create a git tag, and commit changes.

• Push the release branch and tag, then create a Pull Request to main:

git push origin release-x.y.z
git push origin --tags

• Once the PR is reviewed and merged into main, the release workflow will automatically publish to PyPI.

• The workflow verifies the tag is on the main branch before publishing, preventing accidental releases from feature branches.

Credits

This library is based on roslibjs and to a large extent, it is a line-by-line port to Python, changing only where a more idiomatic form makes sense, so a huge part of the credit goes to the roslibjs authors.

Changelog

All notable changes to this project will be documented in this file.

The format is based on Keep a Changelog and this project adheres to Semantic Versioning.

2.1.0

Added

• Added an asyncio transport backend (Autobahn running on an asyncio event loop instead of the Twisted reactor) selectable with ROSLIBPY_TRANSPORT, set_default_transport(), or the Ros(..., transport=...) argument.

• Added transport-parametrized ROS integration tests for CPython, while keeping IronPython on the cli transport.

Changed

• Updated the package classifiers to 3.9-3.14 (removes most EOL python versions, 3.9 is still supported).

Fixed

Deprecated

Removed

2.0.1

Added

Changed

Fixed

• Fixed reconnection on the Twisted transport failing after a connection had been idle for more than a few seconds: connect now schedules the connection through the reactor thread so an idle reactor is woken to service it (previously the new connector was added from another thread and the reactor, blocked in select(), never noticed it).

Deprecated

Removed

2.0.0

Added

• Added ROS 2 action client support.

• Added wait_goal method to ActionClient to block until a goal reaches a terminal state.

• Moved actionlib module to roslibpy.ros1 namespace.

Changed

Fixed

• Fixed KeyError in ROS 2 ActionClient when receiving action results with different message formats from rosbridge.

Deprecated

Removed

1.8.1

Added

Changed

Fixed

• Fixed ROS connection issue on IronPython.

Deprecated

Removed

1.8.0

Added

• Added websocket header support to the ROS-client.

Changed

Fixed

Deprecated

Removed

1.7.0

Added

• Added a ROS 2 compatible header class in roslibpy.ros2.Header.

Changed

Fixed

Deprecated

Removed

1.6.0

Added

• Added authentication functionality described in [rosauth](http://wiki.ros.org/rosauth).

Changed

Fixed

Deprecated

Removed

1.5.0

Added

• Added a wait event to close on IronPython to ensure the close request is sent before returning.

Changed

Fixed

• Fixed reconnection behavior on IronPython which would trigger reconnects even after a manual disconnect.

Deprecated

Removed

1.4.2

Added

Changed

• Added tls to the twisted requirement (#111).

Fixed

Deprecated

Removed

1.4.1

Added

Changed

Fixed

• Fixed bug with action client/server and now they work as expected.

• Fixed Python 2.7 incompatibilities introduced in 1.4.0.

Deprecated

Removed

1.4.0

Added

Changed

• Switched to black for python code formatting.

• Fix incompatible settings between black and flake8.

• Updated Github Actions workflows to remove python 3.6 builds.

• Replaced occurrences of raise Exception with more specific Exception subclasses.

Fixed

Deprecated

Removed

1.3.0

Added

• Added function to set the default timeout value.

• Added ROS host and port parameters to the command-line interface.

Fixed

• Fixed #87 where a goal could be marked as terminal on result alone rather than both result and status.

• Ensure input of Time is always two integers.

1.2.1

Added

Changed

Fixed

• Fixed blocking issues on the Twisted/Autobahn-based implementation of websockets.

Deprecated

Removed

1.2.0

Changed

• Changed behavior: Advertising services automatically reconnect when websockets is reconnected.

• References to ROS master change to ROS.

Added

• Added Header and Time data types.

• Added ROS API method to retrieve current ROS time: ros.get_time.

1.1.0

Added

• Added set_initial_delay, set_max_delay and set_max_retries to RosBridgeClientFactory to control reconnection parameters.

• Added closing event to Ros class that gets triggered right before closing the connection.

1.0.0

Changed

• Changed behavior: Topics automatically reconnect when websockets is reconnected.

Added

• Added blocking behavior to more ROS API methods: ros.get_nodes and ros.get_node_details.

• Added reconnection support to IronPython implementation of websockets.

• Added automatic topic reconnection support for both subscribers and publishers.

Fixed

• Fixed reconnection issues on the Twisted/Autobahn-based implementation of websockets.

0.7.1

Fixed

• Fixed blocking service calls for Mac OS.

0.7.0

Changed

• The non-blocking event loop runner run() now defaults to 10 seconds timeout before raising an exception.

Added

• Added blocking behavior to ROS API methods, e.g. ros.get_topics.

• Added command-line mode to ROS API, e.g. roslibpy topic list.

• Added blocking behavior to the Param class.

• Added parameter manipulation methods to Ros class: get_param, set_param, delete_param.

0.6.0

Changed

• For consistency, timeout parameter of Goal.send() is now expressed in seconds, instead of milliseconds.

Deprecated

• The timeout parameter of ActionClient() is ignored in favor of blocking until the connection is established.

Fixed

• Raise exceptions when timeouts expire on ROS connection or service calls.

Added

• Support for calling a function in a thread from the Ros client.

• Added implementation of a Simple Action Server.

0.5.0

Changed

• The non-blocking event loop runner now waits for the connection to be established in order to minimize the need for on_ready handlers.

Added

• Support blocking and non-blocking service calls.

Fixed

• Fixed an internal unsubscribing issue.

0.4.1

Fixed

• Resolve reconnection issues.

0.4.0

Added

• Add a non-blocking event loop runner.

0.3.0

Changed

• Unsubscribing from a listener no longer requires the original callback to be passed.

0.2.1

Fixed

• Fix JSON serialization error on TF Client (on Python 3.x).

0.2.0

Added

• Add support for IronPython 2.7.

Changed

• Handler on_ready now defaults to run the callback in thread.

Deprecated

• Rename run_event_loop to the more fitting run_forever.

0.1.1

Fixed

• Minimal documentation fixes.

0.1.0

Added

• Initial version.