Developing the plugin system¶
this page is intended for people wanting to contribute to the plugin system in
aiida-core and is not needed for people who just want to contribute a plugin.
Only restrict plugin developers when really necessary;
Avoid schema changes whenever reasonably possible;
Finding and loading plugins must be as fast as the plugin allows, especially for command line interface (CLI) commands. In other words, directly importing a plugin class should not be noticeably faster than using the plugin loader/factory;
Implement as a drop-in replacement, provide backwards compatibility at first, think about changing interfaces if/when the old system is dropped;
Plugin management should be as user friendly from ipython as from the CLI.
A unique name identifying the plugin. Suggested naming scheme is
pypi distribution / repo name: aiida-<plugin_name>
import name: aiida_<plugin_name>
entry point names: <plugin_name>.name
The entry point for a plugin class looks as follows:
name = <module_path>:<classname>
Therefore within a plugin category the name allows us to find a specific plugin (as well as a typestring) The name is recommended to contain the plugin name (as detailed under
A name given to each area extensible via plugins, one of
Each category maps to an entry point group called:
The plugin loading functionality is defined in
aiida.plugins.entry_point and relies on the reentry PyPI package to find and load entry points.
reentry package is part of the build requirements of
aiida-core as defined in the
This enables the scanning for existing plugins when AiiDA is installed.
If for some reason
reentry is uninstalled or is not found, the plugin system will fall back on
pkg_resources from setuptools, which is slower.