virtualize python packages; vpy to pip is similar to what yarn is to npm
instead of installing packages via venv I came up with an elegant solution
simply run.sh (or run.bat on Windows) to see demo.
peek under the hood, it's very simple.
by changing the directory structure of site-packages and symlinking modules.
instead of:
- your_project/venv/site-packages
- foo (==1.6.1)
- bar (==3.1.4)
the new structure is:
- site-packages (the global one)
- foo_1.6.1
- bar_3.1.4
- your_project/local-site-packages
- foo -> site-packages/foo_1.6.1 (symlink)
- bar -> site-packages/foo_1.6.1 (symlink)
TODO: need to write script to automate the process (probably use requirements.txt or simply pip normally and move everything with prejudice)
install the packages normally via pip:
pip install example-1.0.0now the package is in site-packages/<package> so move it:
# run in python installation path where your site-packages are
mkdir site-packages/<package_version>
mv site-packages/<package> site-packages/<package_version>/<package>in the example above, you would move:
mv site-packages/example site-packages/example_1.0.0/example.py(example.py or just example or wherever your module is)
in your project's directory create directory where packages will be symlinked to their respective versions:
mkdir <your_project>/local-site-packagesnow create symlinks for your packages:
ln -s site-packages/<package_version>/<package>replace <package_version> with the version you want to use in your project. this will not interfere with other projects using other versions of the module.
optionally for compatibility create a symlink from site-packages/<package> to site-packages/<package_version>/<package> where package_version would be the default version used
before running your project, change where packages are loaded from:
export PYTHONPATH=<your_project>/local-site-packagesand now python will load modules from this directory. they are simply symlinks to the globally installed modules in site-packages.
now run your project normally:
python project.py