yconf

|Travis|_ |Pypi|_

A wrapper for combining yaml configuration files and command line argument parsing. It builds upon PyYAML_ for parsing yaml config files and argparse_ for handling command line arguments and adds the clue produce one unified program configuration.

Requirements

• Python 2.7+ or 3.2+
• PyYAML >= 3.1

Configuration Environments

Because configuration often differs depending on the environment, e.g. production and testing settings, yconf allows you to define multiple environments in a single configuration. The current supported environemts are production, staging and development. For convenience, yconf is able to merge environment configuration to reduce redundancy, meaning that if the environment is set to staging, the configuration will inherit all settings available in a production environment and override them with staging values where neseccary.

Example

config.yml

::

    production:
      rundir: /var/run/example
      database: /var/lib/example/db.sqlite
      loglevel: warning

    staging:
      database: :memory:

    development:
      loglevel: debug

Configuration

::

    # production environment
    config.rundir: /var/run/example
    config.database: /var/lib/example/db.sqlite
    config.loglevel: warning

    # staging environment
    config.rundir: /var/run/example
    config.database: :memory:
    config.loglevel: warning

    # development environment
    config.rundir: /var/run/example
    config.database: :memory:
    config.loglevel: debug

Both `staging` and `development` environments are optional.

If a directory is specified instead of a configuration file, yconf will
look for configuration files by convention of <environment>.yml in that
directory and merge them accordingly if possible.


Command Line Arguments
----------------------

Extending the argument list supported by a configuration will require subclassing `yconf.BaseConfiguration` and overriding the `makeParser` method.

Example

::

  import sys
  from yconf import BaseConfiguration

  class MyConfig(BaseConfiguration):

    def makeParser(self):
      parser = super(MyConfig, self).makeParser()
      parser.add_argument("-f", "--foo", dest="foo")
      return parser


  config = MyConfig()
  config.parse(sys.argv[1:])


The following configuration arguments are already preset:

  - `-c` Path to configuration file or directory
  - `-e` The environment used for configuration (default: production)

When present, command line argument always take precedent over configuration settings. To override nested yaml values, a dotted destination path can be set for the argument.

config.yml

::

    logging:
      loglevel: debug

Argument

::

    parser.add_argument("--log-level", dest="logging.loglevel")


Accessing Configuration
-----------------------

Configuration can be accessed either by attribute or by key.

::

  config = MyConfig()
  config.parse(args)

  config.foo == config['foo']
  config.foo.bar == config['foo']['bar']



.. _PyYAML: http://pyyaml.org/
.. _argparse: http://pypi.python.org/pypi/argparse
.. |Travis| image:: https://travis-ci.org/kampka/yconf.png?branch=master
.. _Travis: https://travis-ci.org/kampka/yconf/jobs/167164716#
.. |Pypi| image:: https://badge.fury.io/py/yconf.svg
.. _Pypi: https://badge.fury.io/py/yconf