marten 0.5.2

Stupid simple Python configuration management

Marten

Stupid simple Python configuration management

Inspired by node config, if you’ve used it before, Marten will feel familiar with a couple of extras

Tested with Python 2.7 and 3.5

---

Install

> pip install marten

Usage

Marten provides several ways to load configurations, the simplest being the bundled config automatically created by Marten using files found in the .marten/ directory

> mkdir .marten
> echo "EXAMPLE = True" > .marten/default.py
> marten
{
    "EXAMPLE": true
}

The marten command outputs the fully parsed content of the bundled Marten config in JSON format

The bundled config is available in Python at marten.config, and can be accessed like a normal dictionary

> python
>>> from marten import config
>>> config['EXAMPLE']
True

Features

Swappable Configurations

Marten can easily swap between different configurations using the MARTEN_ENV environment variable

The MARTEN_ENV variable defaults to default

> marten
{
    "EXAMPLE": true
}
> echo "SECOND_FILE = 'This is a different environment'" > .marten/two.py
> echo "THIRD_FILE = 'This is a third environment'" > .marten/three.py
> MARTEN_ENV=two marten
{
    "SECOND_FILE": "This is a different environment"
}
> MARTEN_ENV=three marten
{
    "THIRD_FILE": "This is a third environment"
}

Full Python

The configuration files are not parsed, but are imported as Python modules

Only capitalized variables not starting with underscores are read into the configuration, allowing other variables to be used for logic and setup

> echo "a = 1; _B = 2; FULL_PYTHON = a + _B == 3" > .marten/python.py
> MARTEN_ENV=python marten
{
    "FULL_PYTHON": true
}

Multiple File Formats

Marten is not limited to Python files

> echo '{"KEY": "value"}' > .marten/formats.json
> MARTEN_ENV=formats marten
{
    "KEY": "value"
}

Current supported formats:

• Python

• JSON

• YAML

Environment Variable Expansion

Environment variables in values with the format $VAR or ${VAR} are automatically expanded

Unset environment variables are unmodified

> echo '{"REPLACED1": "This ${ENV}", "REPLACED2": "Second $ENV", "IGNORED": "${MISSING}"}' > .marten/environ.json
> MARTEN_ENV=environ ENV=value marten
{
    "IGNORED": "${MISSING}",
    "REPLACED1": "This value",
    "REPLACED2": "Second value"
}

Merge Multiple Files

Since Marten operates on filename and extension separately, two files with the same name but different extensions are merged together in the order they are loaded

> echo 'PYTHON = True' > .marten/merge.py
> echo '{"JSON": true}' > .marten/merge.json
> echo 'YAML: true' > .marten/merge.yaml
> MARTEN_ENV=merge marten
{
    "JSON": true,
    "PYTHON": true,
    "YAML": true
}

License

Available under the MIT license

See LICENSE for more details