Add-On Communication


There are different ways to communication between add-ons inside Home Assistant.

Network

We use a internal network. That allow to speak with every add-on or from Home Assistant to add-on by name or alias. Only the add-ons which runs on the host network are a bit limited. They can speak with all internal add-ons over their name but all other add-on can’t address the add-on in question with its name. But using an alias work well. Thus the name/alias is used to communicate inside Hass.io. The name have the following format {REPO}-{SLUG}, e.g. local-xy or 3283fh-myaddon.

Use hassio to speak with the internal API.

Home Assistant

An add-on can speak to the Home Assistant API with our internal proxy. That makes it very easy to communicate with the API without knowing the password, port or any other information of the Home Assistant instance. Use this URL: http://hassio/homeassistant/api and internal communication is redirected to the right place. The next stept is to add homeassistant_api: true to config.json and read the environment variable API_TOKEN and use this as Home-Assistant password.

It is also possible to speak direct to the Home Assistant instance which is named homeassistant over our internal network. But you need to know the configuration that is used by the running instance.

We have severals services for Hass.io inside Home Assistant to execute tasks. To send data over STDIN to an add-on use the simply hassio.addon_stdin service.

Hass.io API

To enables calls to the Hass.io API, add hassio_api: true to config.json and read the environment variable API_TOKEN. Now you can use the API over the URL: http://hassio/. Use the API_TOKEN with header X-HASSIO-KEY.