Conda-Press¶
Press conda packages into wheels.
The wheels created by conda-press are usable in a general Python setting, i.e. outside of a conda managed environment.
Quick start¶
Run the conda press
command and point it at either an artifact
file or spec. For example:
# from artifact spec, produces single wheel, including all non-Python requirements
$ conda press --subdir linux-64 --skip-python --fatten scikit-image=0.15.0=py37hb3f55d8_2
# from artifact file, produces a single wheel
$ conda press numpy-1.14.6-py36he5ce36f_1201.tar.bz2
# from artifact spec, produces wheels for package and all requirements
$ conda press --subdir linux-64 xz=5.2.4=h14c3975_1001
# merge many wheels into a single wheel
$ conda press --merge *.whl -output scikit_image-0.15.0-2_py37hb3f55d8-cp37-cp37m-linux_x86_64.whl
What we are solving¶
conda-press allows us to build out a pip-usable package index which is ABI compatible with conda packages. This can help address the following issues / workflows:
Issue 1:
It can be very difficult to build wheels for packages that have C extensions. Also, the provenance of wheels with C extentions can be hard to know (who built it, how it was built, etc.). Conda-press enables community building of wheels, based on conda-forge provided packages. This should make it very easy to build a valid wheel.
Issue 2:
Many packages with compiled extensions do not have wheels available on one or more popular platforms (Windows, Mac, Linux). This is because building wheels can be very difficult. Conda has a lot of packages that are not available as wheels otherwise. Conda-press allows these packages to easily become generally usable wheels.
Issue 3:
Some people want a package index built on newer ABIs than manylinux<N>.
Issue 4:
Conda-Press addresses the issue of making shared library dependencies loadable at runtime by having a unix-like directory structure inside of the site-packages/ directory. This allows wheels to have a common $RPATH that they can all point to.
How to install¶
From conda:
conda install -c conda-forge conda-press
From the source code:
$ pip install --no-deps .
More technical details about what we are doing¶
What conda-press does is take an artifact or spec, and turn it into wheel(s). When using pip to install such a wheel, it shoves the root level of the artifact into site-packages. It then provides wrapper / proxy scripts that point to site-packages/bin so that you may run executables and scripts.
Dependencies¶
Conda-press currently has the following external dependencies,
Run Time:
xonsh
lazyasd
ruamel.yaml
tqdm
requests
conda (installed in the current environment)
All of these dependencies are available in conda-forge.
Contributing¶
We highly encourage contributions to conda-press! If you would like to contribute, it is as easy as forking the repository on GitHub, making your changes, and issuing a pull request. If you have any questions about this process don’t hesitate to ask on the Gitter channel.
See the Developer’s Guide for more information about contributing.