igor-inotify 0.4

inotify based managment system

A Runner/Manager of plugins that perform work in response to filesystem events

The intended usage of this is to manage creation/deletion of containers by symlinking into a ‘containers-enabled’ directory

Starting the App

Igor is relativly simple and in most cases cna be run without arguments. -v can be specified multiple times to increase the verbosity of logging to stdout and -c can be used to override the default config file

example:

$ igor

igor also understand/can override the default config dirs with the 2 following environment variables

• IGOR_CONFIG_DIR: The directory to look for config files in

• IGOR_CONFIG: The full path to igor’s config file. If this is not specified, igor looks for ‘igor.conf’ in IGOR_CONFIG_DIR

To get a list of all possible environment variables that can be set, use the following command:

$ python -m igor.consts

Plugins

Plugins are defined in a config file ending in *.conf in the IGOR_CONFIG_DIR. These files are a yaml file with at least 2 keys:

• name: The name of the plugin, mainly used for logging

• plugin: The path to the plugin in the form path/to/module/on/the/filesystem[:name of the setup function] where the name of the setup function is optional and defaults to ‘setup’

In a plugin there exists a single setup function that takes 3 arguments, a config, a logger and a way to generate inotify instances

• config: The Yaml config file that defines this plugin as python objects including the ‘name’ and ‘plugin’ as defined above. any extra keys in the config file automatically get passed in via config.

• logger: logging.getLogger instance that has been set up for this plugin with the correct logging policy applied

• inotify: Takes a callable and returns a butter.inotify.Inotify instance that allows the adding of watches (listening for events is done by igor). The callable provided is called on each inotify event and is given a butter.inotify.InotifyEvent object

for an example of how this works, take a look at ‘inotify.py’ and ‘inotify.conf’ in example_fs