Multipart device automations on iOS

An automation may reference multipart devices similarly to an automation that doesn't use multipart devices.

First, obtain the component part(s) as you would normally. See Multipart devices for how to work with multipart devices.

Then, for each part you want to use in your automation, create an AutomationPartPath, which lets you reference the part in automation starters, conditions, and actions.

//  Obtain a reference to the device:
let multipartDevices = try await self.home.devices(enableMultipartDevices: true).list()

let light = multipartDevices.first(where: {
  $0.parts.contains(OnOffLightDeviceType.self) && $0.structureID == structure.id
})

let lightDeviceType = await light.parts.get(OnOffLightDeviceType.self)

let lightPartPath = light.automationPart(lightDeviceType)

Another thing to note is that automation actions usually take a device and a device type as parameters. However, an automation action that references a component part device - again, using an AutomationPartPath - only needs the AutomationPartPath, because the AutomationPartPath already contains a reference to the device type in addition to the component device reference.

For example, in the Automation API, a Refrigerator device type may be treated as a multipart device. It consists of a root RefrigeratorDevice which can contain multiple subpart cabinets, such as freezers or standard cabinets of type TemperatureControlledCabinetDevice.

To build refrigerator automations, you primarily interact with two standard Matter traits:

  • RefrigeratorAlarm: Exposes door status alarms through the doorOpen attribute of the state field.
  • RefrigeratorAndTemperatureControlledCabinetMode: Allows reading and commanding modes. For example, running commands like changeToMode to switch to modes like LowEnergy, RapidCool, or LowNoise.

This example automation triggers when the refrigerator door is opened. If the door is left open for more than two minutes, the automation broadcasts a voice notification on smart speakers, flashes the kitchen lights, and sends a push notification. Note that this automation impacts only the refrigerator compartment of the device, ignoring the freezer compartment (if it exists):

import GoogleHomeSDK
import GoogleHomeTypes

typealias RefrigeratorAlarmTrait = Matter.RefrigeratorAlarmTrait
typealias OnOffTrait = Matter.OnOffTrait

// Fetch devices using the multipart device model.
let multipartDevices = try await self.home.devices(enableMultipartDevices: true).list()

// Obtain a reference to the refrigerator device.
guard let refrigeratorDevice = multipartDevices.first {
    $0.types.contains(TemperatureControlledCabinetDeviceType.self) &&
    $0.traits.contains(Matter.RefrigeratorAndTemperatureControlledCabinetModeTrait.self) &&
    $0.traits.contains(Matter.RefrigeratorAlarmTrait.self)
  }

let refrigeratorDeviceType = await refrigeratorDevice.parts.get(RefrigeratorDeviceType.self).first

// Get all temperature-controlled cabinet parts of the refrigerator
let cabinets = refrigeratorDeviceType.parts(type: TemperatureControlledCabinetDeviceType.self)

// Find the cabinet part with the 'refrigerator' semantic tag
let refrigeratorCabinet = cabinets.first {
  $0.metadata.tags.contains(SemanticTag.Refrigerator.refrigerator)
}
var cabinetPartPath = refrigeratorDevice.automationPart(refrigeratorCabinet)

let structure = home.structures().list().first

let speaker = multipartDevices.first(where: {
        $0.types.contains(SpeakerDeviceType.self) && $0.structureID == structure.id
      })

let refrigeratorDoorAlert = automation(
  name: "Refrigerator Door Open Alert",
  description: "Warn when the refrigerator door has been open for over 2 min."
) {
  // 1. Starter: Monitor the refrigerator door alarm trait
  let alarmStarter = starter(
    cabinetPartPath,
    RefrigeratorAlarmTrait.self
  )

  alarmStarter

  // 2. Condition: Ensure the 'doorOpen' alarm remains active for 120 seconds
  condition(for: .seconds(120)) {
    alarmStarter.state.doorOpen.equals(true)
  }

  // 3. Actions: Execute parallel reactions
  parallel {
    // Broadcast warning to household speakers
    action(speaker, SpeakerDeviceType.self) {
      Google.AssistantBroadcastTrait.broadcast(msg: "The refrigerator door has been left open!")
    }

    // Push a notification alerts to home members' mobile devices
    action(structure) {
      Google.NotificationTrait.sendNotifications(
        title: "Fridge Alert",
        body: "The refrigerator door has been open for over 2 min.",
        optInMemberEmailsArray: ["222larabrown@gmail.com"]
      )
    }
  }
}

The following example switches the refrigerator to Low Energy mode when it detects that no one is home.

import GoogleHomeSDK
import GoogleHomeTypes

typealias AreaPresenceStateTrait = Google.AreaPresenceStateTrait
typealias RefrigeratorAndTemperatureControlledCabinetModeTrait = Matter.RefrigeratorAndTemperatureControlledCabinetModeTrait

let structure = home.structures().list().first()

// Fetch devices using the multipart device model.
let devices = try await self.home.devices(enableMultipartDevices: true).list()

// Obtain a reference to the refrigerator device.
guard let refrigeratorDevice = multipartDevices.first {
    $0.types.contains(TemperatureControlledCabinetDeviceType.self) &&
    $0.traits.contains(Matter.RefrigeratorAndTemperatureControlledCabinetModeTrait.self) &&
    $0.traits.contains(Matter.RefrigeratorAlarmTrait.self)
  }

let refrigeratorDeviceType = await refrigeratorDevice.parts.get(RefrigeratorDeviceType.self)

// Get all temperature-controlled cabinet parts of the refrigerator
let cabinets = refrigeratorDeviceType.parts(type: TemperatureControlledCabinetDeviceType.self)

// Find the cabinet part with the 'refrigerator' semantic tag
let refrigeratorCabinet = cabinets.first {
  $0.metadata.tags.contains(SemanticTag.Refrigerator.refrigerator)
}

let cabinetPartPath = refrigeratorDevice.automationPart(refrigeratorCabinet)

let refrigeratorEcoMode = automation(
  name: "Refrigerator Eco Mode",
  description: "Automatically changes refrigerator to low energy mode when house is vacant."
) {
  // 1. Starter: Monitor household presence changes
  let presenceStarter = starter(structure, AreaPresenceStateTrait.self)

  presenceStarter

  // 2. Condition: Verify presence state transitions to vacant
  condition {
    presenceStarter.presenceState.equals(.presenceStateVacant)
  }
  // 3. Action: Set refrigerator cabinet Mode to 'Low Energy' (commonly option index 1)
  action(cabinetPartPath) {
    RefrigeratorAndTemperatureControlledCabinetModeTrait.changeToMode(newMode: 1)
  }
}
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