catkin_tools_python

This is a buildtype plugin for catkin_tools which allows building plain Python packages as part of the isolated catkin workspace. Because catkin_tools is not able to see a package or resolve dependencies without a package.xml file in the package directory, there is also included a script which can be used before the build to spider the workspace, and create the missing package.xml files for Python packages, based on the PKG-INFO file which is standard with the Python sdist archive format.

What it isn't: This plugin does not allow Python packages to be built via the conventional catkin_make or catkin_make_isolated tools, nor does it allow plain Python packages to be released using Bloom.

Demonstration

You'll want to set up a virtualenv with catkin_tools and this package in it:

virtualenv catkin_tools_env
source catkin_tools_env/bin/activate
pip install -U pip
pip install git+https://github.com/mikepurvis/catkin_tools_python.git

Then create a workspace with some regular ROS packages in it, and also add in a bunch of plain Python packages, downloaded directly from PyPI, using the included tool to fill in the missing package.xml files:

mkdir -p demo_ws/src && cd demo_ws
rosinstall_generator ros_base --deps --tar --rosdistro indigo > src/.rosinstall
curl https://gist.githubusercontent.com/mikepurvis/530df5cd34967f6a0aded2fea5c440db/raw/ros-base-python.yaml >> src/.rosinstall
wstool up -t src -j8
create_python_package_xmls src

Now build that workspace. Note that we can't use the default "linked" develspace configuration, since that requires building catkin before everything else, and catkin's dependencies are now here in the workspace—they need to build first!

catkin config --isolate-devel --merge-install --install
catkin build

When the build is complete, you can source the workspace and confirm that you are using the libraries built into the workspace rather than your system copies:

source install/setup.bash
python -c 'import yaml; print yaml.__file__'

Note that this is just one of many possible workflows. If you don't want to generate the package.xml files at build time as shown above, you could commit them along with the upstream code into git repos, which would allow rosdistro_build_cache to cache them and permit them to be resolved by rosinstall_generator.