google-assistant-mqtt

Implementation of the Google Actions Smarthome interface for MQTT.

NOTE: requests a resync 10 seconds after boot.

You need to create 2 config files. Examples are provided.

TODO: OAuth thing is really hacky and not safe to leave running. Project just a WIP at the moment.

TODO: need to implement willReportState:true... believe it will be faster.

devices.yml

Contains a list of devices with their traits.

Refer to Device Types and Device Traits to construct new devices.

• The device type seems to mostly just change the icon in the app.
• The device traits provide the commands, attributes and state available on the device.
• The documentation on device types has a good list of examples and common traits for that type, but you can mix it up as you want.
• Commands have associated phrases for triggering.

Examples

Basic Switch

• The switch only has 1 trait: OnOff.
• The OnOff also has a command OnOff and a boolean state on.
• Turning the switch on/off via Google Assistant will call the OnOff command.
• When the OnOff command is run 2 MQTT events are fired:
  • Topic: mqtthome/my_switch/OnOff Body: {"on":true}
  • Topic: mqtthome/my_switch/OnOff/on Body: true

- id: "my_switch"
  type: "action.devices.types.SWITCH"
  traits:
    - "action.devices.traits.OnOff"
  name:
    defaultNames:
      - "my switch"
    name: "my switch"
    nicknames:
      - "my switch"
  willReportState: false
  roomHint: "Master Bedroom"

More Useful Switch

You could listen on the automatically fired events to toggle the actual switch. Alternatively you can send additional events by setting mqtt.out.

• When the OnOff command is run an extra event is fired:
  • Topic: switches/001/power Body: true

- id: "my_switch"
  type: "action.devices.types.SWITCH"
  traits:
    - "action.devices.traits.OnOff"
  name:
    defaultNames:
      - "my switch"
    name: "my switch"
    nicknames:
      - "my switch"
  willReportState: false
  roomHint: "Master Bedroom"
  mqtt:
    out:
      "OnOff/on": "switches/001/power"

Synchronised State Switch

State is automatically remembered from past commands, but if the device is controlled from elsewhere, like a switch on the wall, we might need to sync state back.

• Assuming when a user physically toggles the switch an event on the switches/001/power/status is fired:
  • The on state will be updated to the value in the event.

- id: "my_switch"
  type: "action.devices.types.SWITCH"
  traits:
    - "action.devices.traits.OnOff"
  name:
    defaultNames:
      - "my switch"
    name: "my switch"
    nicknames:
      - "my switch"
  willReportState: false
  roomHint: "Master Bedroom"
  mqtt:
    out:
      "OnOff/on": "switches/001/power"
    in:
      "on": "switches/001/power/status"

Full Example

See devices.example.yml for more examples.

config.yml

Contains config for the service.

See config.example.yml for an example.

# This is supposed to uniquely identify the account in your system.
# Makes sense for something like Hue cloud, but because you'll be the only user just make something constant.
agentUserId: mqtt-home

# Make up something for client credentials.
# You'll have to enter this in Google when setting things up.
clientId: mqtt-home
clientSecret: put_something_really_secret_here

# This is required to authenticate with Google
googleProjectId: get_from_google
# This is required to request a resync
googleApiKey: get_this_from_goole

# This is required for the OAuth flow.
# Just put something longish and random here.
code: for_hacky_oauth_thing_code
# The hacky OAuth implementation will _always_ return the same access token.
# (Even when refreshing)
accessToken: for_hacky_oauth_thing_access
# The hacky OAuth implementation will _always_ return the same refresh token.
refreshToken: for_hacky_oauth_thing_refresh

# MQTT target
mqttUri: mqtt://localhost
# Automatically published events will be prefixed with this.
mqttBaseTopic: mqtthome/