Python config parsing helper for click
click-config
provides a decorator that takes a python object and overwrites its attributes with values passed into the program via command line arguments.
Usage:
Create an entry point for your project (e.g: main.py):
from __future__ import print_function
import click
import click_config
class config(object):
class logger(object):
level = 'INFO'
class mysql(object):
host = 'localhost'
@click.command()
@click_config.wrap(module=config, sections=('logger', 'mysql'))
def main():
print('log level: {}, mysql host: {}'.format(
config.logger.level,
config.mysql.host
))
if __name__ == '__main__':
main()
$ python main.py --help
Usage: main.py [OPTIONS]
Options:
--conf-mysql TEXT
--conf-logger TEXT
-c, --conf PATH
--help Show this message and exit.
The click_config.wrap
decorator creates options for each one of the sections
:
$ python main.py --conf-logger "level: WARN"
log level: WARN, mysql host: localhost
You can also use the --conf
option to pass in yaml files:
$ echo "logger: {level: WARN}" > /tmp/logger.yaml
$ echo "mysql: {host: remotehost}" > /tmp/mysql.yaml
$ python main.py --conf /tmp/mysql.yaml --conf /tmp/logger.yaml
log level: WARN, mysql host: remotehost
You can also use conf.d style configurations and pass --conf
to recursively traverse a directory
$ echo "logger: {level: WARN}" > /tmp/conf.d/logger.yaml
$ echo "mysql: {host: remotehost}" > /tmp/conf.d/mysql.yaml
$ python main.py --conf /tmp/conf.d
log level: WARN, mysql host: remotehost
Finally, you can use the CONF
environment variable as an alternative to the --conf
command line option, use ':' as the delimiter:
$ echo "logger: {level: WARN}" > /tmp/logger.yaml
$ echo "mysql: {host: remotehost}" > /tmp/mysql.yaml
$ CONF=/tmp/mysql.yaml:/tmp/logger.yaml python main.py
log level: WARN, mysql host: remotehost
inotify support (ALPHA):
click-config
also supports watching files using inotify
and tornado
.
To enable this feature you must install click-config
with the inotify
extra.
$ pip install 'click-config[inotify]'
To watch files simply invoke click_config.wrap()
with watch=True
The configuration module will automatically be updated when the files change.
When using this feature, the wrapped function will receive a watcher
parameter which you can use to listen for key change events.
def on_key_change(section, key, value):
pass
@click.command()
@click_config.wrap(module=config, sections=('logger', 'mysql'), watch=True)
def main(watcher):
watcher.add_listener(('mysql', 'host'), on_key_change) # watch a specific key
watcher.add_listener(('mysql', ), on_key_change) # watch all keys in the 'mysql' section
watcher.add_listener(watcher.ALL, on_key_change) # watch all keys in all sections
watcher.io_loop.start()
NOTES:
click-config
will parse any file ending with.conf
,.ini
,.yml
or.yaml
..conf
and.ini
are loaded with ConfigParser.yml
and.yaml
are loaded with a yaml parser- A configuration object must be modeled in a 2 level hierarchy like an
.ini
file, where keys are stored under a section.