PDM - Python Development Master
A modern Python package manager with PEP 582 support. 中文版本说明
What is PDM?
PDM is meant to be a next generation Python package management tool.
It is originally built for personal interest. If you feel you are going well
Poetry and don't want to introduce another package manager,
just stick to it. But if you are missing something that is not present in those tools,
you can probably find some goodness in
Highlights of features
- PEP 582 local package installer and runner, no virtualenv involved at all.
- Simple and relatively fast dependency resolver, mainly for large binary distributions.
- A PEP 517 build backend.
- A full-featured plug-in system.
Why not virtualenv?
Now the majority of Python packaging tools also act as virtualenv managers. It is for the benifit of isolating project environments. But things will get tricky when it comes to nested venvs: One installs the virtualenv manager using a venv capsulated Python, and create more venvs using the tool which is based on a capsulated Python. One day a minor release of Python out and one has to check all those venvs and upgrade them if required.
While PEP 582, in the other hand, introduce a way to decouple Python interpreter with project environments. It is a relative new proposal and there are not many tools supporting it, among which there is pyflow, but it is written with Rust and can't get much help from the big Python community. Moreover, due to the same reason, it can't act as a PEP 517 backend.
PDM requires python version 3.7 or higher.
It is recommended to install
pdm in an isolated enviroment, with
$ pipx install pdm
Or you can install it under user site:
$ pip install --user pdm
python -m pdm --help should be a good guidance.
1. What is put in
PEP 582 is a draft proposal which still needs a lot of polishment, for instance, it doesn't mention how to manage
CLI executables. PDM take the decision to put
include together with
2. How do I run CLI scripts in the local package directory?
The recommended way is to prefix your command with
pdm run. It is also possible to run CLI scripts directly from
the outside, the PDM's installer has already injected the package path to the
sys.path in the entry script file.
3. What site-packages will be loaded when using PDM?
PDM first looks to
__pypackages__ but will fall back to looking in site-packages. This is not entirely hermetic
and could lead to some confusion around which packages are being used, though.
4. Can I relocate or move the
__pypackages__ folder for deployment?
You'd better not. The packages installed inside
__pypackages__ are OS dependent. Instead, you should keep
in VCS and do
pdm sync on the target environment to deploy.
5. Can I use
pdm to manage a Python 2.7 project?
pdm itself can be installed under Python 3.7+ only, but it doesn't restrict the Python used by the project.
This project is open sourced under MIT license, see the LICENSE file for more details.