Generic Platform Discovery
New controller or hub components often need to add platforms in sub-components (i.e. Lights & Switches) without additional configuration.
This can be achieved using the load_platform
or async_load_platform
methods from homeassistant.helpers.discovery
:
def load_platform(hass, component, platform, discovered=None, hass_config=None)
From more info on how this works, refer to the load_platform method.
Example
Say you need to implement your new MyFlashyHub that controls both Switches & Lights, you can follow these steps:
Configuration required for your new hub component:
myflashyhub:
example: setting
The source for your component can be located in your configuration directory for now:
~/.homeassistant/custom_components/myflashyhub.py
~/.homeassistant/custom_components/light/myflashyhub.py
~/.homeassistant/custom_components/switch/myflashyhub.py
In the hub component myflashyhub.py
you can call your light and switch components. To pass any non-serializable information to the platforms in the sub-component, you can use a global variable.
from homeassistant.helpers.discovery import load_platform
DOMAIN = 'myflashyhub'
DATA_MFH = 'MFH'
def setup(hass, config):
"""Your controller/hub specific code."""
hass.data[DATA_MFH] = SomeObjectToInitialiseGlobal()
#--- snip ---
load_platform(hass, 'light', DOMAIN)
load_platform(hass, 'switch', DOMAIN, {'optional': 'arguments'})
Add your custom device specific code to the setup_platform
method in light/myflashyhub.py
and switch/myflashyhub
.
import custom_components.myflashyhub as myflashyhub
# 'switch' will receive discovery_info={'optional': 'arguments'}
# as passed in above. 'light' will receive discovery_info=None
def setup_platform(hass, config, add_devices, discovery_info=None):
"""Your switch/light specific code."""
# You can now use hass.data[myflashyhub.DATA_MFH]
The load_platform
method allows the platforms to be loaded without the need for any additional platform entries in your configuration.yaml
file, which normally would have been:
#light:
# platform: myflashyhub
#switch:
# platform: myflashyhub