Checklist for creating a component

A checklist of things to do when you’re adding a new component.

Not all existing platforms follow the requirements in this checklist. This cannot be used as a reason to not follow them!

1. Requirements

1. Requirement version pinned: REQUIREMENTS = ['phue==0.8.1']
2. We no longer want requirements hosted on GitHub. Please upload to PyPi.
3. Requirements should only be imported inside functions. This is necessary because requirements are installed on the fly.

2. Configuration

1. Voluptuous schema present for config validation
2. Default parameters specified in voluptuous schema, not in setup(…)
3. Schema using as many generic config keys as possible from homeassistant.const
4. If your component has platforms, define a PLATFORM_SCHEMA instead of a CONFIG_SCHEMA.
5. If using a PLATFORM_SCHEMA to be used with EntityComponent, import base from homeassistant.helpers.config_validation
6. Never depend on users adding things to customize to configure behavior inside your component.

3. Component/platform communication

1. If you need to share global data with platforms, use the dictionary hass.data. hass.data[DATA_XY] while XY is the component is preferred over hass.data[DOMAIN].
2. If the component fetches data that causes its related platform entities to update, you can notify them using the dispatcher code in homeassistant.helpers.dispatcher.