Schema for configuration.yaml

For the corresponding configuration.yaml:

geniushub:
  host: 192.168.0.1
  username: username
  password: password

... use the voluptuous schema:

DOMAIN = 'geniushub'

CONF_TOKEN = 'hub_token'
CONF_HOST = 'host'
CONF_USERNAME = 'username'
CONF_PASSWORD = 'password'

_V1_API_SCHEMA = vol.Schema({
    vol.Required(CONF_TOKEN): str,
})
_V3_API_SCHEMA = vol.Schema({
    vol.Required(CONF_HOST): str,
    vol.Required(CONF_USERNAME): str,
    vol.Required(CONF_PASSWORD): str,
})
CONFIG_SCHEMA = vol.Schema({
    DOMAIN: vol.Any(
        _V3_API_SCHEMA,
        _V1_API_SCHEMA,
    )
}, extra=vol.ALLOW_EXTRA)

... and the following code:

kwargs = dict(hass_config[DOMAIN])
if CONF_HOST in kwargs:
    args = (kwargs.pop(CONF_HOST), )
else:
    args = (kwargs.pop(CONF_TOKEN), )

try:
    client = GeniusHubClient(
        *args, **kwargs, session=async_get_clientsession(hass)
    )