Support extending the device fields populated in the "get-state" event

Change-type: minor

src/features/device-state/index.ts

@@ -3,6 +3,7 @@ import type StrictEventEmitter from 'strict-event-emitter-types';
 
 import { EventEmitter } from 'events';
 import { middleware } from '../../infra/auth';
+import type { Device } from '../../balena-model';
 
 import { resolveOrDenyDevicesWithStatus } from './middleware';
 import { stateV2 } from './routes/state-get-v2';
@@ -14,9 +15,10 @@ import {
 	statePatchV3,
 } from './routes/state-patch-v3';
 import { fleetStateV3 } from './routes/fleet-state-get-v3';
-import { Device } from '../../balena-model';
+import type { GetStateEventStoredDeviceFields } from './state-get-utils';
 
 export {
+	getStateEventAdditionalFields,
 	getConfig,
 	setReadTransaction,
 	filterDeviceConfig,
@@ -74,7 +76,10 @@ export interface Events {
 		info: Pick<Request, 'apiKey'> & {
 			config?: Dictionary<string>;
 			ipAddress: string | undefined;
+			// TODO: Drop in the next major
+			/** @deprecated use the storedDeviceFields */
 			storedPublicAddress: Device['public_address'];
+			storedDeviceFields: GetStateEventStoredDeviceFields;
 		},
 	) => void;
 }

src/features/device-state/routes/state-get-v2.ts

@@ -15,6 +15,7 @@ import {
 	ConfigurationVarsToLabels,
 	getStateDelayingEmpty,
 	getConfig,
+	getStateEventAdditionalFields,
 } from '../state-get-utils';
 import { sbvrUtils } from '@balena/pinejs';
 import { events } from '..';
@@ -194,7 +195,7 @@ const stateQuery = _.once(() =>
 		resource: 'device',
 		id: { uuid: { '@': 'uuid' } },
 		options: {
-			$select: ['device_name', 'public_address'],
+			$select: ['device_name', ...getStateEventAdditionalFields],
 			$expand: {
 				device_config_variable: {
 					$select: ['name', 'value'],
@@ -250,7 +251,9 @@ const getStateV2 = async (req: Request, uuid: string): Promise<StateV2> => {
 		apiKey: req.apiKey,
 		config,
 		ipAddress: getIP(req),
+		// TODO: Drop in the next major in favor of storedDeviceFields
 		storedPublicAddress: device.public_address as Device['public_address'],
+		storedDeviceFields: _.pick(device, getStateEventAdditionalFields),
 	});
 
 	const userApp = getUserAppForState(device, config);

src/features/device-state/routes/state-get-v3.ts

@@ -12,6 +12,7 @@ import {
 	getConfig,
 	getReleaseForDevice,
 	getStateDelayingEmpty,
+	getStateEventAdditionalFields,
 	readTransaction,
 	serviceInstallFromImage,
 	varListInsert,
@@ -270,7 +271,7 @@ const stateQuery = _.once(() =>
 		resource: 'device',
 		id: { uuid: { '@': 'uuid' } },
 		options: {
-			$select: ['device_name', 'public_address'],
+			$select: ['device_name', ...getStateEventAdditionalFields],
 			$expand: deviceExpand,
 		},
 	}),
@@ -287,7 +288,9 @@ const getStateV3 = async (req: Request, uuid: string): Promise<StateV3> => {
 		apiKey: req.apiKey,
 		config,
 		ipAddress: getIP(req),
+		// TODO: Drop in the next major in favor of storedDeviceFields
 		storedPublicAddress: device.public_address as Device['public_address'],
+		storedDeviceFields: _.pick(device, getStateEventAdditionalFields),
 	});
 
 	let apps = getUserAppState(device, config);

src/features/device-state/state-get-utils.ts

@@ -8,6 +8,19 @@ import {
 	createMultiLevelStore,
 	reqPermissionNormalizer,
 } from '../../infra/cache';
+import type { Device } from '../../balena-model';
+
+// eslint-disable-next-line @typescript-eslint/no-empty-interface -- This needs to be an interface so that downstream projects can extend it.
+export interface GetStateEventStoredDeviceFields
+	extends Pick<Device, 'public_address'> {}
+
+// We do not use "satisfies" or "as const" so that downstream projects can augment this list.
+export const getStateEventAdditionalFields: Array<
+	keyof GetStateEventStoredDeviceFields
+> = [
+	// TODO: Remove the public_address from this list in the next major since it's not used by oB-api and downstream projects can set it if needed.
+	'public_address',
+];
 
 const defaultConfigVariableFns: Array<(config: Dictionary<string>) => void> = [
 	function setMinPollInterval(config) {