glueplate

Glueplate provides composable settings for Python frameworks and libraries. Settings are dictionaries that support attribute access, recursive merging, list extension, and inheritance from other Glueplate configurations.

Installation

python -m pip install glueplate

Glueplate requires Python 3.11 or later.

Define base settings

Create a module that exports a settings value. GLUE_PLATE_ENVIRONMENT_VARIABLE_KEY names the environment variable that points to the user's settings module.

from glueplate import Glue

settings = Glue(
    GLUE_PLATE_ENVIRONMENT_VARIABLE_KEY='MY_APP_SETTINGS_MODULE',
    debug=False,
    paths=['base'],
    database={'host': 'localhost', 'port': 5432},
)

Set GLUE_PLATE_BASE_MODULE to that module and the configured environment variable to the user's module.

export GLUE_PLATE_BASE_MODULE=my_app.default_settings
export MY_APP_SETTINGS_MODULE=my_project.settings

The user's module only needs to contain overrides.

from glueplate import Glue

settings = Glue(
    debug=True,
    database={'host': 'database.example.com'},
)

Load the merged settings through glueplate.config.

from glueplate import config

assert config.settings.debug is True
assert config.settings.database.host == 'database.example.com'
assert config.settings.database.port == 5432

Extend lists

Use GLUE_PLATE_PLUS_BEFORE_ or GLUE_PLATE_PLUS_AFTER_ followed by the target setting name.

from glueplate import Glue

settings = Glue(
    GLUE_PLATE_PLUS_BEFORE_paths=['project-first'],
    GLUE_PLATE_PLUS_AFTER_paths=['project-last'],
)

The merged value is ['project-first', 'base', 'project-last'].

Inherit settings

A base settings module can include other Glueplate settings modules.

from glueplate import Glue

settings = Glue(
    GLUE_PLATE_ENVIRONMENT_VARIABLE_KEY='MY_APP_SETTINGS_MODULE',
    GLUE_PLATE_PARENT_MODULES=[
        'another_library.default_settings',
    ],
)

Development

The development environment is managed with uv.

uv sync --locked
uv run pytest
uv run ruff check .
uv run pyrefly check
uv build
uv run twine check dist/*

License

Glueplate is distributed under the MIT License.