localconfig

A simplified interface to ConfigParser using dot notion with data type / comment support.

Feature Summary

• Simple access to config using dot notion and iterators

• Full compatibility with ConfigParser ini formats (as that is used as the backend)

• Data type support by intelligently guessing the data types based on value on read.

• Multiple config source input (read from string, file pointer, file, or list of them)

• Full comment support / retention on save

• Lazy reading of config sources for performance (only read when a config value is accessed)

Quick Start Tutorial

To install:

pip install localconfig

Let’s say we have a script named program with the following config in ~/.config/program:

[Web Server]
# Server host
host = 0.0.0.0

# Server port
port = 8080

# Debug logging
debug = off

To read the config, simply do:

from localconfig import config

start_server(config.web_server.host, config.web_server.port, config.web_server.debug)

# Or use get method:
# start_server(config.get('Web Server', 'host'),
#              config.get('Web Server', 'port'),
#              config.get('web_server', 'debug'))  # Yes, 'web_server' also works here!
#
# Or if the config is in docstring, read from it:
# config.read(__doc__)
#
# Or if the config file is elsewhere:
# config.read('/etc/path/to/config.ini')  # Non-existing file is ignored
#
# Or read from a list of sources
# config.read(['string config', file_path, file_pointer, io.StringIO('config')])
#
# Or create another instance for another config:
# from localconfig import LocalConfig
# config2 = LocalConfig('/etc/path/to/another/config.ini')

Configs are read in the order they are called using config.read(), but the config file passed to the LocalConfig() constructor (defaults to ~/.config/$script_name) will be read last before the first access to config values, which allows us to read configs from various locations, like default configs from a string that is checked in with the code, while allowing them to be overrriden from the config file that is passed to the constructor.

Now, let’s do some inspection:

# Iterate over sections and their keys/values
for section in config:
  print(section)                   # Web Server

  for key, value in config.items(section):
    print(key, value, type(value)) # host 0.0.0.0 <type 'str'>
                                   # port 8080 <type 'int'>
                                   # debug False <type 'bool'>

sections = list(config)            # ['Web Server']

# Iterate over keys/values
for key, value in config.web_server:
  print(key, value, type(value))    # Same output as above config.items()

items = list(config.web_server)    # [('host', '0.0.0.0'), ('port', 8080), ('debug', False)]
items = dict(config.web_server)    # {'host': '0.0.0.0', 'port': 8080, 'debug': False}

# Check if a section or key is set - any non-existing section or key defaults to None.
if config.web_server or config.no_such_section:
  pass

if config.web_server and (config.web_server.port or config.web_server.no_such_key):
  pass

To add a section and set a value:

config.add_section('App Server', comment='Settings for application server')
config.app_server.host = 'localhost'

# Use `set` if you want to set a comment
config.set('App Server', 'port', 9090, comment='App server port')

# Set value for the DEFAULT section (default value for all other sections)
config.env = 'prod'

To write the config:

config.save()

# Or simply get the config as a string:
# config_str = str(config)
#
# Or save to a different location:
# config.save('/path/to/save/to.ini')

If we open ~/.config/program now, we would see:

[DEFAULT]

env = prod


[Web Server]

# Server host
host = 0.0.0.0

# Server port
port = 8080

# Debug logging
debug = off


# Settings for application server
[App Server]

host = localhost

# App server port
port = 9090

Supported Data Types

Data type is guessed based on the value and converted on read.

The following types are supported:

Remote Config

Check out: https://pypi.python.org/pypi/remoteconfig

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