pdm-conda

A PDM plugin to resolve/install/uninstall project dependencies with Conda.

Configuration

Config item	Description	Default value	Possible values	Environment variable
conda.active	Force plugin usage or not	True		PDM_CONDA_ACTIVE
conda.runner	Conda runner executable	conda	conda, mamba, micromamba	PDM_CONDA_RUNNER
conda.solver	Solver to use for Conda resolution	conda	conda, libmamba	PDM_CONDA_SOLVER
conda.channels	Conda channels to use, order will be enforced	[]
conda.as-default-manager	Use Conda to install all possible requirements	False		PDM_CONDA_AS_DEFAULT_MANAGER
conda.batched-commands	Execute batched install and remove Conda commands, when True the command is executed only at the end	False		PDM_CONDA_BATCHED_COMMANDS
conda.excludes	Array of dependencies to exclude from Conda resolution	[]
conda.auto-excludes	If cannot find package with Conda, add it to excludes list	False		PDM_CONDA_AUTO_EXCLUDES
conda.installation-method	Installation method to use when installing dependencies with Conda	hard-link	hard-link, copy	PDM_CONDA_INSTALLATION_METHOD
conda.dependencies	Array of dependencies to install with Conda, analogue to project.dependencies	[]
conda.optional-dependencies	Groups of optional dependencies to install with Conda, analogue to project.optional-dependencies	{}
conda.dev-dependencies	Groups of development dependencies to install with Conda, analogue to tool.pdm.dev-dependencies	{}
conda.pypi-mapping.download-dir	PyPI-Conda mapping download directory	$HOME/.pdm-conda/		PDM_CONDA_PYPI_MAPPING_DIR
conda.pypi-mapping.url	PyPI-Conda mapping url	https://github.com/regro/cf-graph-countyfair/raw/master/mappings/pypi/grayskull_pypi_mapping.yaml		PDM_CONDA_PYPI_MAPPING_URL

All configuration items use prefix pdm.tool, this is a viable configuration:

[tool.pdm.conda]
runner = "micromamba"
channels = ["conda-forge/noarch", "conda-forge", "anaconda"]
dependencies = ["pdm"]
as-default-manager = true
auto-excludes = true
solver = "libmamba"
excludes = ["pytest-cov"] # don't install with conda even if it's a dependency from other packages
installation-method = "copy"
batched-commands = true
active = false

[tool.pdm.conda.pypi-mapping]
download-dir = "/tmp"
url = "https://url/to/mapping.yaml"

[tool.pdm.conda.optional-dependencies]
extra = ["anaconda:ffmpeg"] # non python dependency, obtained from anaconda channel

[tool.pdm.conda.dev-dependencies]
dev = ["pytest"]

Usage

This plugin adds capabilities to the default PDM commands.

Working commands

The following commands were tested and work:

• pdm init:
  • To list/use Conda managed python you must specify the Conda runner with -cr or --runner.
  • You also can specify a default Conda channel with -c or --channel.
• pdm lock
• pdm install
• pdm add:
  • To add a Conda managed package --conda flag can be used multiple times followed a package (analogue to --editable).
  • You can specify per package Conda channel using conda notation channel::package.
  • You also can specify a default Conda channel with -c or --channel.
  • With flag -r or --runner you can specify the Conda runner to use.
  • With flag -ce or --conda-excludes you can add PyPi packages to the excluded from Conda resolution.
  • With flag --conda-as-default-manager you can set conda.as-default-manager to True.
• pdm remove
• pdm update
• pdm list
• pdm info
• pdm use
• pdm venv:
  • create:
    • To list/use Conda managed python you must specify the Conda runner with -w or --with.
    • You can completely override the Conda environment name with -cn or --conda-name, the resulting environment won't follow PDM environment naming conventions.
  • list
  • remove

How it works

Using conda/libmamba solver

PDM invokes Conda solver to resolve conda packages each time a PDM candidate makes a change in the last Conda resolution.

If only Conda packages are used (i.e. setting conda.as-default-manager to true and no conda.excludes) then Conda solver is invoked only once.

Settings overridden

In order to use Conda to install packages some settings were overriden:

• python.use_venv if conda settings detected in pyproject.toml this setting is set to True.
• python.in_project if conda settings detected in pyproject.toml and this setting was not previously set then is set to False.
• python.use_pyenv if conda settings detected in pyproject.toml this setting is set to False.
• venv.backend if conda settings detected in pyproject.toml this setting is set to conda.runner.
• venv.location if conda settings detected in pyproject.toml, VIRTUAL_ENV or CONDA_PREFIX environment variables are set and this setting was not previously set then is set to the value of the environment variable.
• install.parallel if some Conda managed packages are to be uninstalled or updated this option is disabled momentarily.

Some environment variables were overridden too:

• PDM_IGNORE_ACTIVE_VENV if conda settings detected in pyproject.toml and VIRTUAL_ENV or CONDA_PREFIX environment variables are set then this variable is set to False.

All this changes will be maintained only during the execution of the command, after that the settings will be restored to the previous values.

Lock strategy

• Lock strategy no_cross_platform for pdm lock is always forced as Conda doesn't produce cross-platform locks.
• Lock strategy static_urls for Conda managed packages is always forced, independently of the lock strategy used for PyPi packages.
• Lock strategy direct_minimal_versions for Conda managed packages will partially work as Conda doesn't have an option to force this mode on a resolution.

Development

For development docker-compose files exist in deploy directory, helper script deploy/docker-compose.sh can be used for executing docker.

For running dev environment:

bash deploy/docker-compose.sh -d up

And for productive environment:

bash deploy/docker-compose.sh up