Update @balena/lint to v7

This updates balena lint to the latest version to enable eslint support
and unblock Typescript updates. This is a huge number of changes as the
linting rules are much more strict now, requiring modifiying most files
in the codebase. This commit also bumps the test dependency `rewire` as
that was interfering with the update of balena-lint

Change-type: patch

.lintstagedrc

@@ -2,10 +2,4 @@
 	"*.ts": [
 		"balena-lint --typescript --fix",
 	],
-	"*.js": [
-		"balena-lint --typescript --fix",
-	],
-	"test/**/*.ts": [
-		"balena-lint --typescript --no-prettier --tests"
-	],
 }

package.json

@@ -10,7 +10,7 @@
   "scripts": {
     "start": "./entry.sh",
     "build": "npm run clean && npm run release && webpack",
-    "lint": "balena-lint -e ts -e js src/ test/ typings/ build-utils/ webpack.config.js",
+    "lint": "balena-lint -e ts -e js src/ test/ typings/ build-utils/",
     "test:build": "tsc --noEmit && tsc --noEmit --project tsconfig.js.json",
     "test:unit": "mocha --config test/unit/.mocharc.js",
     "test:integration": "find test/integration -name *.spec.ts | xargs -n 1 -I {} sh -c 'mocha --config test/integration/.mocharc.js {} || exit 255'",
@@ -21,7 +21,7 @@
     "test:compose": "(ARCH=$(./build-utils/detect-arch.sh) docker compose -f docker-compose.yml -f docker-compose.test.yml run --build --rm sut || docker compose logs); npm run compose:down",
     "test": "npm run lint && npm run test:build && npm run test:unit",
     "compose:down": "docker compose -f docker-compose.yml -f docker-compose.test.yml down --volumes",
-    "prettify": "balena-lint -e ts -e js --fix src/ test/ typings/ build-utils/ webpack.config.js",
+    "prettify": "balena-lint -e ts -e js --fix src/ test/ typings/ build-utils/",
     "release": "tsc --project tsconfig.release.json && mv build/src/* build",
     "sync": "ts-node --files sync/sync.ts",
     "clean": "rimraf build",
@@ -42,7 +42,7 @@
     "@balena/contrato": "^0.6.0",
     "@balena/es-version": "^1.0.1",
     "@balena/happy-eyeballs": "0.0.6",
-    "@balena/lint": "^6.2.0",
+    "@balena/lint": "^7.3.0",
     "@types/bluebird": "^3.5.37",
     "@types/chai": "^4.3.3",
     "@types/chai-as-promised": "^7.1.5",
@@ -53,6 +53,7 @@
     "@types/dockerode": "^2.5.34",
     "@types/event-stream": "^3.3.34",
     "@types/express": "^4.17.14",
+    "@types/json-mask": "2.0.3",
     "@types/lodash": "^4.14.186",
     "@types/memoizee": "^0.4.8",
     "@types/mocha": "^8.2.3",
@@ -116,7 +117,7 @@
     "request": "^2.88.2",
     "resin-docker-build": "^1.1.6",
     "resumable-request": "^2.0.1",
-    "rewire": "^5.0.0",
+    "rewire": "^6.0.0",
     "rimraf": "^2.7.1",
     "rwlock": "^5.0.0",
     "semver": "7.5.4",

src/api-binder/index.ts

@@ -147,7 +147,7 @@ export async function start() {
 	}
 
 	log.debug('Starting current state report');
-	await startCurrentStateReport();
+	void startCurrentStateReport();
 
 	// When we've provisioned, try to load the backup. We
 	// must wait for the provisioning because we need a
@@ -158,7 +158,7 @@ export async function start() {
 
 	readyForUpdates = true;
 	log.debug('Starting target state poll');
-	TargetState.startPoll();
+	void TargetState.startPoll();
 	// Update and apply new target state
 	TargetState.emitter.on(
 		'target-state-update',
@@ -235,7 +235,7 @@ export function startCurrentStateReport() {
 			'Trying to start state reporting without initializing API client',
 		);
 	}
-	startReporting();
+	return startReporting();
 }
 
 export async function fetchDeviceTags(): Promise<DeviceTag[]> {

src/api-binder/report.ts

@@ -1,17 +1,17 @@
 import * as url from 'url';
-import * as _ from 'lodash';
+import type { CoreOptions } from 'request';
-import { CoreOptions } from 'request';
 import { performance } from 'perf_hooks';
 import { setTimeout } from 'timers/promises';
 import { readFile } from 'fs/promises';
 
 import { DeviceState } from '../types';
 import * as config from '../config';
-import { SchemaTypeKey, SchemaReturn } from '../config/schema-type';
+import type { SchemaTypeKey, SchemaReturn } from '../config/schema-type';
 import * as eventTracker from '../event-tracker';
 import * as deviceState from '../device-state';
 
-import { withBackoff, OnFailureInfo } from '../lib/backoff';
+import type { OnFailureInfo } from '../lib/backoff';
+import { withBackoff } from '../lib/backoff';
 import { log } from '../lib/supervisor-console';
 import { InternalInconsistencyError, StatusError } from '../lib/errors';
 import { getRequestInstance } from '../lib/request';

src/app.ts

@@ -107,7 +107,9 @@ async function mdnsLookup(
 	// Make NodeJS RFC 3484 compliant for properly handling IPv6
 	// See: https://github.com/nodejs/node/pull/14731
 	//      https://github.com/nodejs/node/pull/17793
-	const dns = require('dns');
+	// We disable linting for the next line. The require call
+	// is necesary for monkey-patching the dns module
+	const dns = require('dns'); // eslint-disable-line
 	const { lookup } = dns;
 
 	dns.lookup = (

src/compose/app.ts

@@ -1,18 +1,18 @@
 import * as _ from 'lodash';
 import { promises as fs } from 'fs';
-import { ImageInspectInfo } from 'dockerode';
+import type { ImageInspectInfo } from 'dockerode';
 
 import Network from './network';
 import Volume from './volume';
 import Service from './service';
 import * as imageManager from './images';
 import type { Image } from './images';
-import {
+import type {
 	CompositionStep,
-	generateStep,
 	CompositionStepAction,
 } from './composition-steps';
-import * as targetStateCache from '../device-state/target-state-cache';
+import { generateStep } from './composition-steps';
+import type * as targetStateCache from '../device-state/target-state-cache';
 import { getNetworkGateway } from '../lib/docker-utils';
 import * as constants from '../lib/constants';
 import {
@@ -22,7 +22,7 @@ import {
 import { isNotFoundError } from '../lib/errors';
 import * as config from '../config';
 import { checkTruthy } from '../lib/validation';
-import { ServiceComposeConfig, DeviceMetadata } from './types/service';
+import type { ServiceComposeConfig, DeviceMetadata } from './types/service';
 import { pathExistsOnRoot } from '../lib/host-utils';
 import { isSupervisor } from '../lib/supervisor-metadata';
 
@@ -64,7 +64,10 @@ export class App {
 	public networks: Network[];
 	public volumes: Volume[];
 
-	public constructor(opts: AppConstructOpts, public isTargetState: boolean) {
+	public constructor(
+		opts: AppConstructOpts,
+		public isTargetState: boolean,
+	) {
 		this.appId = opts.appId;
 		this.appUuid = opts.appUuid;
 		this.appName = opts.appName;
@@ -513,12 +516,18 @@ export class App {
 			return;
 		}
 
-		const needsDownload = !context.availableImages.some(
+		const needsDownload =
+			target != null &&
+			!context.availableImages.some(
 				(image) =>
-				image.dockerImageId === target?.config.image ||
+					image.dockerImageId === target.config.image ||
-				imageManager.isSameImage(image, { name: target?.imageName! }),
+					imageManager.isSameImage(image, { name: target.imageName! }),
 			);
-		if (needsDownload && context.downloading.includes(target?.imageName!)) {
+		if (
+			target != null &&
+			needsDownload &&
+			context.downloading.includes(target.imageName!)
+		) {
 			// The image needs to be downloaded, and it's currently downloading.
 			// We simply keep the application loop alive
 			return generateStep('noop', {});

src/compose/application-manager.ts

@@ -1,9 +1,10 @@
 import * as _ from 'lodash';
 import { EventEmitter } from 'events';
-import StrictEventEmitter from 'strict-event-emitter-types';
+import type StrictEventEmitter from 'strict-event-emitter-types';
 
 import * as config from '../config';
-import { transaction, Transaction } from '../db';
+import type { Transaction } from '../db';
+import { transaction } from '../db';
 import * as logger from '../logger';
 import LocalModeManager from '../local-mode';
 
@@ -25,9 +26,9 @@ import * as networkManager from './network-manager';
 import * as serviceManager from './service-manager';
 import * as imageManager from './images';
 import * as commitStore from './commit';
-import Service from './service';
+import type Service from './service';
-import Network from './network';
+import type Network from './network';
-import Volume from './volume';
+import type Volume from './volume';
 import { generateStep, getExecutors } from './composition-steps';
 
 import type {
@@ -45,11 +46,11 @@ type ApplicationManagerEventEmitter = StrictEventEmitter<
 	{ change: DeviceLegacyReport }
 >;
 const events: ApplicationManagerEventEmitter = new EventEmitter();
-export const on: typeof events['on'] = events.on.bind(events);
+export const on: (typeof events)['on'] = events.on.bind(events);
-export const once: typeof events['once'] = events.once.bind(events);
+export const once: (typeof events)['once'] = events.once.bind(events);
-export const removeListener: typeof events['removeListener'] =
+export const removeListener: (typeof events)['removeListener'] =
 	events.removeListener.bind(events);
-export const removeAllListeners: typeof events['removeAllListeners'] =
+export const removeAllListeners: (typeof events)['removeAllListeners'] =
 	events.removeAllListeners.bind(events);
 
 const localModeManager = new LocalModeManager();
@@ -611,7 +612,7 @@ export async function serviceNameFromId(serviceId: number) {
 			(svcName) => services[svcName].id === serviceId,
 		);
 
-		if (!!serviceName) {
+		if (serviceName) {
 			return serviceName;
 		}
 	}
@@ -771,7 +772,7 @@ function saveAndRemoveImages(
 		: availableAndUnused.filter((image) => !deltaSources.includes(image.name));
 
 	return imagesToSave
-		.map((image) => ({ action: 'saveImage', image } as CompositionStep))
+		.map((image) => ({ action: 'saveImage', image }) as CompositionStep)
 		.concat(imagesToRemove.map((image) => ({ action: 'removeImage', image })));
 }
 
@@ -948,7 +949,7 @@ export async function getState() {
 		// We cannot report services that do not have an image as the API
 		// requires passing the image name
 		.filter(([, img]) => !!img)
-		.map(([svc, img]) => ({ ...img, ...svc } as ServiceInfo))
+		.map(([svc, img]) => ({ ...img, ...svc }) as ServiceInfo)
 		.map((svc, __, serviceList) => {
 			// If the service is not running it cannot be a handover
 			if (svc.status !== 'Running') {

src/compose/composition-steps.ts

@@ -4,15 +4,15 @@ import * as config from '../config';
 
 import type { Image } from './images';
 import * as images from './images';
-import Network from './network';
+import type Network from './network';
-import Service from './service';
+import type Service from './service';
 import * as serviceManager from './service-manager';
-import Volume from './volume';
+import type Volume from './volume';
 
 import { checkTruthy } from '../lib/validation';
 import * as networkManager from './network-manager';
 import * as volumeManager from './volume-manager';
-import { DeviceLegacyReport } from '../types/state';
+import type { DeviceLegacyReport } from '../types/state';
 import * as commitStore from './commit';
 
 interface BaseCompositionStepArgs {
@@ -81,7 +81,7 @@ interface CompositionStepArgs {
 	saveImage: {
 		image: Image;
 	};
-	cleanup: {};
+	cleanup: object;
 	createNetwork: {
 		target: Network;
 	};
@@ -94,8 +94,8 @@ interface CompositionStepArgs {
 	removeVolume: {
 		current: Volume;
 	};
-	ensureSupervisorNetwork: {};
+	ensureSupervisorNetwork: object;
-	noop: {};
+	noop: object;
 }
 
 export type CompositionStepAction = keyof CompositionStepArgs;

src/compose/errors.ts

@@ -10,7 +10,10 @@ export class InvalidNetworkNameError extends TypedError {
 }
 
 export class ResourceRecreationAttemptError extends TypedError {
-	public constructor(public resource: string, public name: string) {
+	public constructor(
+		public resource: string,
+		public name: string,
+	) {
 		super(
 			`Trying to create ${resource} with name: ${name}, but a ${resource} ` +
 				'with that name and a different configuration already exists',

src/compose/images.ts

@@ -1,12 +1,13 @@
-import * as Docker from 'dockerode';
+import type * as Docker from 'dockerode';
 import { EventEmitter } from 'events';
 import * as _ from 'lodash';
-import StrictEventEmitter from 'strict-event-emitter-types';
+import type StrictEventEmitter from 'strict-event-emitter-types';
 
 import * as config from '../config';
 import * as db from '../db';
 import * as constants from '../lib/constants';
-import { DeltaFetchOptions, FetchOptions, docker } from '../lib/docker-utils';
+import type { DeltaFetchOptions, FetchOptions } from '../lib/docker-utils';
+import { docker } from '../lib/docker-utils';
 import * as dockerUtils from '../lib/docker-utils';
 import {
 	DeltaStillProcessingError,
@@ -67,11 +68,11 @@ class ImageEventEmitter extends (EventEmitter as new () => StrictEventEmitter<
 >) {}
 const events = new ImageEventEmitter();
 
-export const on: typeof events['on'] = events.on.bind(events);
+export const on: (typeof events)['on'] = events.on.bind(events);
-export const once: typeof events['once'] = events.once.bind(events);
+export const once: (typeof events)['once'] = events.once.bind(events);
-export const removeListener: typeof events['removeListener'] =
+export const removeListener: (typeof events)['removeListener'] =
 	events.removeListener.bind(events);
-export const removeAllListeners: typeof events['removeAllListeners'] =
+export const removeAllListeners: (typeof events)['removeAllListeners'] =
 	events.removeAllListeners.bind(events);
 
 const imageFetchFailures: Dictionary<number> = {};
@@ -144,15 +145,17 @@ function reportEvent(event: 'start' | 'update' | 'finish', state: Image) {
 		switch (event) {
 			case 'start':
 				return true; // always report change on start
-			case 'update':
+			case 'update': {
 				const [updatedTask, changedAfterUpdate] = currentTask.update(state);
 				runningTasks[imageName] = updatedTask;
 				return changedAfterUpdate; // report change only if the task context changed
-			case 'finish':
+			}
+			case 'finish': {
 				const [, changedAfterFinish] = currentTask.finish();
 				delete runningTasks[imageName];
 				return changedAfterFinish; // report change depending on the state of the task
 			}
+		}
 	})();
 
 	if (stateChanged) {
@@ -551,7 +554,7 @@ const inspectByReference = async (imageName: string) => {
 			filters: { reference: [reference] },
 		})
 		.then(([img]) =>
-			!!img
+			img
 				? docker.getImage(img.Id).inspect()
 				: Promise.reject(
 						new StatusError(
@@ -582,7 +585,7 @@ const inspectByDigest = async (imageName: string) => {
 		// Assume that all db entries will point to the same dockerImageId, so use
 		// the first one. If this assumption is false, there is a bug with cleanup
 		.then(([img]) =>
-			!!img
+			img
 				? docker.getImage(img.dockerImageId).inspect()
 				: Promise.reject(
 						new StatusError(

src/compose/network.ts

@@ -1,5 +1,5 @@
 import * as _ from 'lodash';
-import * as dockerode from 'dockerode';
+import type * as dockerode from 'dockerode';
 
 import { docker } from '../lib/docker-utils';
 import logTypes = require('../lib/log-types');
@@ -7,7 +7,7 @@ import * as logger from '../logger';
 import log from '../lib/supervisor-console';
 import * as ComposeUtils from './utils';
 
-import {
+import type {
 	ComposeNetworkConfig,
 	NetworkConfig,
 	NetworkInspectInfo,
@@ -22,7 +22,9 @@ export class Network {
 	public name: string;
 	public config: NetworkConfig;
 
-	private constructor() {}
+	private constructor() {
+		/* do not allow instances using `new` */
+	}
 
 	private static deconstructDockerName(
 		name: string,

src/compose/ports.ts

@@ -15,7 +15,7 @@ export interface PortBindings {
 }
 
 export interface DockerPortOptions {
-	exposedPorts: Dictionary<{}>;
+	exposedPorts: Dictionary<EmptyObject>;
 	portBindings: PortBindings;
 }
 
@@ -49,7 +49,7 @@ export class PortMap {
 			this.ports.externalEnd,
 		);
 
-		const exposedPorts: { [key: string]: {} } = {};
+		const exposedPorts: { [key: string]: EmptyObject } = {};
 		const portBindings: PortBindings = {};
 
 		_.zipWith(internalRange, externalRange, (internal, external) => {

src/compose/sanitise.ts

@@ -1,6 +1,6 @@
 import * as _ from 'lodash';
 
-import { ConfigMap, ServiceComposeConfig } from './types/service';
+import type { ConfigMap, ServiceComposeConfig } from './types/service';
 
 import log from '../lib/supervisor-console';
 

src/compose/service-manager.ts

@@ -1,10 +1,10 @@
-import * as Dockerode from 'dockerode';
+import type * as Dockerode from 'dockerode';
 import { EventEmitter } from 'events';
 import { isLeft } from 'fp-ts/lib/Either';
 import * as JSONStream from 'JSONStream';
 import * as _ from 'lodash';
 import { promises as fs } from 'fs';
-import StrictEventEmitter from 'strict-event-emitter-types';
+import type StrictEventEmitter from 'strict-event-emitter-types';
 
 import * as config from '../config';
 import { docker } from '../lib/docker-utils';
@@ -12,15 +12,16 @@ import * as logger from '../logger';
 
 import { PermissiveNumber } from '../config/types';
 import * as constants from '../lib/constants';
+import type { StatusCodeError } from '../lib/errors';
 import {
 	InternalInconsistencyError,
 	isNotFoundError,
-	StatusCodeError,
 	isStatusError,
 } from '../lib/errors';
 import * as LogTypes from '../lib/log-types';
 import { checkInt, isValidDeviceName } from '../lib/validation';
-import { Service, ServiceStatus } from './service';
+import type { ServiceStatus } from './service';
+import { Service } from './service';
 import { serviceNetworksToDockerNetworks } from './utils';
 
 import log from '../lib/supervisor-console';
@@ -41,11 +42,11 @@ interface KillOpts {
 	wait?: boolean;
 }
 
-export const on: typeof events['on'] = events.on.bind(events);
+export const on: (typeof events)['on'] = events.on.bind(events);
-export const once: typeof events['once'] = events.once.bind(events);
+export const once: (typeof events)['once'] = events.once.bind(events);
-export const removeListener: typeof events['removeListener'] =
+export const removeListener: (typeof events)['removeListener'] =
 	events.removeListener.bind(events);
-export const removeAllListeners: typeof events['removeAllListeners'] =
+export const removeAllListeners: (typeof events)['removeAllListeners'] =
 	events.removeAllListeners.bind(events);
 
 // Whether a container has died, indexed by ID
@@ -359,7 +360,7 @@ export async function start(service: Service) {
 			);
 		}
 
-		logger.attach(container.id, { serviceId, imageId });
+		void logger.attach(container.id, { serviceId, imageId });
 
 		if (!alreadyStarted) {
 			logger.logSystemEvent(LogTypes.startServiceSuccess, { service });
@@ -421,7 +422,7 @@ export function listenToEvents() {
 										`serviceId and imageId not defined for service: ${service.serviceName} in ServiceManager.listenToEvents`,
 									);
 								}
-								logger.attach(data.id, {
+								void logger.attach(data.id, {
 									serviceId,
 									imageId,
 								});
@@ -447,7 +448,7 @@ export function listenToEvents() {
 		});
 	};
 
-	(async () => {
+	void (async () => {
 		try {
 			await listen();
 		} catch (e) {
@@ -479,7 +480,7 @@ export async function attachToRunning() {
 					`containerId not defined for service: ${service.serviceName} in ServiceManager.attachToRunning`,
 				);
 			}
-			logger.attach(service.containerId, {
+			void logger.attach(service.containerId, {
 				serviceId,
 				imageId,
 			});

src/compose/service.ts

@@ -1,10 +1,11 @@
 import { detailedDiff as diff } from 'deep-object-diff';
-import * as Dockerode from 'dockerode';
+import type * as Dockerode from 'dockerode';
 import Duration = require('duration-js');
 import * as _ from 'lodash';
 import * as path from 'path';
 
-import { DockerPortOptions, PortMap } from './ports';
+import type { DockerPortOptions } from './ports';
+import { PortMap } from './ports';
 import * as ComposeUtils from './utils';
 import * as updateLock from '../lib/update-lock';
 import { sanitiseComposeConfig } from './sanitise';
@@ -14,14 +15,16 @@ import * as conversions from '../lib/conversions';
 import { checkInt } from '../lib/validation';
 import { InternalInconsistencyError } from '../lib/errors';
 
-import { EnvVarObject } from '../types';
+import type { EnvVarObject } from '../types';
-import {
+import type {
 	ServiceConfig,
 	ServiceConfigArrayField,
 	ServiceComposeConfig,
 	ConfigMap,
 	DeviceMetadata,
 	DockerDevice,
+} from './types/service';
+import {
 	ShortMount,
 	ShortBind,
 	ShortAnonymousVolume,
@@ -108,7 +111,9 @@ export class Service {
 		'hostname',
 	].concat(Service.allConfigArrayFields);
 
-	private constructor() {}
+	private constructor() {
+		/* do not allow instancing a service object with `new` */
+	}
 
 	// The type here is actually ServiceComposeConfig, except that the
 	// keys must be camelCase'd first
@@ -909,11 +914,11 @@ export class Service {
 	private getBindsMountsAndVolumes(): {
 		binds: string[];
 		mounts: Dockerode.MountSettings[];
-		volumes: { [volName: string]: {} };
+		volumes: { [volName: string]: EmptyObject };
 	} {
 		const binds: string[] = [];
 		const mounts: Dockerode.MountSettings[] = [];
-		const volumes: { [volName: string]: {} } = {};
+		const volumes: { [volName: string]: EmptyObject } = {};
 
 		for (const volume of this.config.volumes) {
 			if (LongDefinition.is(volume)) {
@@ -921,7 +926,11 @@ export class Service {
 				mounts.push(ComposeUtils.serviceMountToDockerMount(volume));
 			} else {
 				// Volumes with the string short syntax are acceptable as Docker configs as-is
-				ShortMount.is(volume) ? binds.push(volume) : (volumes[volume] = {});
+				if (ShortMount.is(volume)) {
+					binds.push(volume);
+				} else {
+					volumes[volume] = {};
+				}
 			}
 		}
 

src/compose/types/network.ts

@@ -1,4 +1,4 @@
-import { NetworkInspectInfo as DockerNetworkInspectInfo } from 'dockerode';
+import type { NetworkInspectInfo as DockerNetworkInspectInfo } from 'dockerode';
 
 // TODO: ConfigOnly is part of @types/dockerode@v3.2.0, but that version isn't
 // compatible with `resin-docker-build` which is used for `npm run sync`.

src/compose/types/service.ts

@@ -1,8 +1,8 @@
-import * as Dockerode from 'dockerode';
+import type * as Dockerode from 'dockerode';
 import * as t from 'io-ts';
 import { isAbsolute } from 'path';
 
-import { PortMap } from '../ports';
+import type { PortMap } from '../ports';
 
 export interface ComposeHealthcheck {
 	test: string | string[];

src/compose/update-strategies.ts

@@ -1,6 +1,7 @@
 import * as imageManager from './images';
-import Service from './service';
+import type Service from './service';
-import { CompositionStep, generateStep } from './composition-steps';
+import type { CompositionStep } from './composition-steps';
+import { generateStep } from './composition-steps';
 import { InternalInconsistencyError } from '../lib/errors';
 import { checkString } from '../lib/validation';
 

src/compose/utils.ts

@@ -1,12 +1,12 @@
-import * as Dockerode from 'dockerode';
+import type * as Dockerode from 'dockerode';
 import Duration = require('duration-js');
 import * as _ from 'lodash';
 import { parse as parseCommand } from 'shell-quote';
 
 import * as constants from '../lib/constants';
 import { checkTruthy } from '../lib/validation';
-import { Service } from './service';
+import type { Service } from './service';
-import {
+import type {
 	ComposeHealthcheck,
 	ConfigMap,
 	DeviceMetadata,
@@ -209,7 +209,7 @@ function getNanoseconds(timeStr: string): number {
 
 export function composeHealthcheckToServiceHealthcheck(
 	healthcheck: ComposeHealthcheck | null | undefined,
-): ServiceHealthcheck | {} {
+): ServiceHealthcheck | EmptyObject {
 	if (healthcheck == null) {
 		return {};
 	}
@@ -351,9 +351,8 @@ export async function addFeaturesFromLabels(
 			} as LongBind);
 
 			if (service.config.environment['DOCKER_HOST'] == null) {
-				service.config.environment[
+				service.config.environment['DOCKER_HOST'] =
-					'DOCKER_HOST'
+					`unix://${constants.containerDockerSocket}`;
-				] = `unix://${constants.containerDockerSocket}`;
 			}
 			// We keep balena.sock for backwards compatibility
 			if (constants.dockerSocket !== '/var/run/balena.sock') {

src/compose/volume-manager.ts

@@ -1,6 +1,6 @@
 import * as _ from 'lodash';
 import * as path from 'path';
-import { VolumeInspectInfo } from 'dockerode';
+import type { VolumeInspectInfo } from 'dockerode';
 
 import { isNotFoundError, InternalInconsistencyError } from '../lib/errors';
 import { safeRename } from '../lib/fs-utils';
@@ -10,7 +10,8 @@ import * as LogTypes from '../lib/log-types';
 import log from '../lib/supervisor-console';
 import * as logger from '../logger';
 import { ResourceRecreationAttemptError } from './errors';
-import Volume, { VolumeConfig } from './volume';
+import type { VolumeConfig } from './volume';
+import Volume from './volume';
 
 export interface VolumeNameOpts {
 	name: string;

src/compose/volume.ts

@@ -1,4 +1,4 @@
-import * as Docker from 'dockerode';
+import type * as Docker from 'dockerode';
 import isEqual = require('lodash/isEqual');
 import omitBy = require('lodash/omitBy');
 
@@ -6,7 +6,7 @@ import * as constants from '../lib/constants';
 import { docker } from '../lib/docker-utils';
 import { InternalInconsistencyError } from '../lib/errors';
 import * as LogTypes from '../lib/log-types';
-import { LabelObject } from '../types';
+import type { LabelObject } from '../types';
 import * as logger from '../logger';
 import * as ComposeUtils from './utils';
 

src/config/backends/backend.ts

@@ -1,5 +1,3 @@
-import * as _ from 'lodash';
-
 export interface ConfigOptions {
 	[key: string]: string | string[];
 }

src/config/backends/config-fs.ts

@@ -2,7 +2,8 @@ import * as _ from 'lodash';
 import { promises as fs } from 'fs';
 import * as path from 'path';
 
-import { ConfigOptions, ConfigBackend } from './backend';
+import type { ConfigOptions } from './backend';
+import { ConfigBackend } from './backend';
 import { exec, exists } from '../../lib/fs-utils';
 import * as hostUtils from '../../lib/host-utils';
 import * as constants from '../../lib/constants';
@@ -49,10 +50,10 @@ export class ConfigFs extends ConfigBackend {
 		const amlSrcPath = path.join(this.SystemAmlFiles, `${aml}.aml`);
 		// log to system log if the AML doesn't exist...
 		if (!(await exists(amlSrcPath))) {
-			log.error(`Missing AML for \'${aml}\'. Unable to load.`);
+			log.error(`Missing AML for '${aml}'. Unable to load.`);
 			if (logger) {
 				logger.logSystemMessage(
-					`Missing AML for \'${aml}\'. Unable to load.`,
+					`Missing AML for '${aml}'. Unable to load.`,
 					{ aml, path: amlSrcPath },
 					'Load AML error',
 					false,

src/config/backends/config-txt.ts

@@ -1,6 +1,7 @@
 import * as _ from 'lodash';
 
-import { ConfigOptions, ConfigBackend } from './backend';
+import type { ConfigOptions } from './backend';
+import { ConfigBackend } from './backend';
 import * as constants from '../../lib/constants';
 import log from '../../lib/supervisor-console';
 import { exists } from '../../lib/fs-utils';
@@ -14,7 +15,7 @@ const ARRAY_CONFIGS = [
 	'gpio',
 ] as const;
 
-type ArrayConfig = typeof ARRAY_CONFIGS[number];
+type ArrayConfig = (typeof ARRAY_CONFIGS)[number];
 
 // Refinement on the ConfigOptions type
 // to indicate what properties are arrays

src/config/backends/extlinux-file.ts

@@ -1,6 +1,6 @@
 import * as _ from 'lodash';
 
-import { ConfigOptions } from './backend';
+import type { ConfigOptions } from './backend';
 import {
 	ExtLinuxParseError,
 	AppendDirectiveError,

src/config/backends/extlinux.ts

@@ -1,13 +1,10 @@
 import * as _ from 'lodash';
 import * as semver from 'semver';
 
-import { ConfigOptions, ConfigBackend } from './backend';
+import type { ConfigOptions } from './backend';
-import {
+import { ConfigBackend } from './backend';
-	ExtlinuxFile,
+import type { ExtlinuxFile, Directive } from './extlinux-file';
-	Directive,
+import { AppendDirective, FDTDirective } from './extlinux-file';
-	AppendDirective,
-	FDTDirective,
-} from './extlinux-file';
 import * as constants from '../../lib/constants';
 import log from '../../lib/supervisor-console';
 import { ExtLinuxEnvError, ExtLinuxParseError } from '../../lib/errors';

src/config/backends/extra-uEnv.ts

@@ -1,6 +1,7 @@
 import * as _ from 'lodash';
 
-import { ConfigOptions, ConfigBackend } from './backend';
+import type { ConfigOptions } from './backend';
+import { ConfigBackend } from './backend';
 import * as constants from '../../lib/constants';
 import log from '../../lib/supervisor-console';
 import { ExtraUEnvError } from '../../lib/errors';

src/config/backends/index.ts

@@ -1,5 +1,3 @@
-import * as _ from 'lodash';
-
 import { Extlinux } from './extlinux';
 import { ExtraUEnv } from './extra-uEnv';
 import { ConfigTxt } from './config-txt';

src/config/backends/odmdata.ts

@@ -1,7 +1,8 @@
 import * as _ from 'lodash';
 import { promises as fs } from 'fs';
 
-import { ConfigOptions, ConfigBackend } from './backend';
+import type { ConfigOptions } from './backend';
+import { ConfigBackend } from './backend';
 import * as constants from '../../lib/constants';
 import log from '../../lib/supervisor-console';
 import { ODMDataError } from '../../lib/errors';

src/config/backends/splash-image.ts

@@ -6,7 +6,8 @@ import * as constants from '../../lib/constants';
 import { exists } from '../../lib/fs-utils';
 import * as hostUtils from '../../lib/host-utils';
 import log from '../../lib/supervisor-console';
-import { ConfigBackend, ConfigOptions } from './backend';
+import type { ConfigOptions } from './backend';
+import { ConfigBackend } from './backend';
 
 export class SplashImage extends ConfigBackend {
 	private static readonly BASEPATH = hostUtils.pathOnBoot('splash');
@@ -155,7 +156,7 @@ export class SplashImage extends ConfigBackend {
 		return SplashImage.CONFIGS.includes(this.stripPrefix(name).toLowerCase());
 	}
 
-	public async matches(_deviceType: string): Promise<boolean> {
+	public async matches(): Promise<boolean> {
 		// all device types
 		return true;
 	}
@@ -191,7 +192,10 @@ export class SplashImage extends ConfigBackend {
 			: await this.readSplashImage(SplashImage.DEFAULT);
 
 		// If it is a data URI get only the data part
-		const [, image] = value.startsWith('data:') ? value.split(',') : [, value];
+		let image = value;
+		if (value.startsWith('data:')) {
+			[, image] = value.split(',');
+		}
 
 		// Rewrite the splash image
 		await this.writeSplashImage(image);

src/config/configJson.ts

@@ -5,7 +5,7 @@ import * as constants from '../lib/constants';
 import * as hostUtils from '../lib/host-utils';
 import * as osRelease from '../lib/os-release';
 import { readLock, writeLock } from '../lib/update-lock';
-import * as Schema from './schema';
+import type * as Schema from './schema';
 
 export default class ConfigJsonConfigBackend {
 	private readonly readLockConfigJson: () => Bluebird.Disposer<() => void>;

src/config/index.ts

@@ -1,18 +1,20 @@
 import { EventEmitter } from 'events';
 import type { Knex } from 'knex';
 import * as _ from 'lodash';
-import StrictEventEmitter from 'strict-event-emitter-types';
+import type StrictEventEmitter from 'strict-event-emitter-types';
 import { inspect } from 'util';
 import { generateUniqueKey } from '../lib/register-device';
 
-import { Either, isLeft, isRight, Right } from 'fp-ts/lib/Either';
+import type { Either, Right } from 'fp-ts/lib/Either';
+import { isLeft, isRight } from 'fp-ts/lib/Either';
 import * as t from 'io-ts';
 
 import ConfigJsonConfigBackend from './configJson';
 
 import * as FnSchema from './functions';
 import * as Schema from './schema';
-import { SchemaReturn, SchemaTypeKey, schemaTypes } from './schema-type';
+import type { SchemaReturn, SchemaTypeKey } from './schema-type';
+import { schemaTypes } from './schema-type';
 
 import * as db from '../db';
 import {
@@ -43,9 +45,9 @@ class ConfigEvents extends (EventEmitter as new () => ConfigEventEmitter) {}
 const events = new ConfigEvents();
 
 // Expose methods which make this module act as an EventEmitter
-export const on: typeof events['on'] = events.on.bind(events);
+export const on: (typeof events)['on'] = events.on.bind(events);
-export const once: typeof events['once'] = events.once.bind(events);
+export const once: (typeof events)['once'] = events.once.bind(events);
-export const removeListener: typeof events['removeListener'] =
+export const removeListener: (typeof events)['removeListener'] =
 	events.removeListener.bind(events);
 
 export async function get<T extends SchemaTypeKey>(
@@ -54,7 +56,7 @@ export async function get<T extends SchemaTypeKey>(
 ): Promise<SchemaReturn<T>> {
 	const $db = trx || db.models;
 
-	if (Schema.schema.hasOwnProperty(key)) {
+	if (Object.prototype.hasOwnProperty.call(Schema.schema, key)) {
 		const schemaKey = key as Schema.SchemaKey;
 
 		return getSchema(schemaKey, $db).then((value) => {
@@ -80,7 +82,7 @@ export async function get<T extends SchemaTypeKey>(
 			// the type system happy
 			return checkValueDecode(decoded, key, value) && decoded.right;
 		});
-	} else if (FnSchema.fnSchema.hasOwnProperty(key)) {
+	} else if (Object.prototype.hasOwnProperty.call(FnSchema.fnSchema, key)) {
 		const fnKey = key as FnSchema.FnSchemaKey;
 		// Cast the promise as something that produces an unknown, and this means that
 		// we can validate the output of the function as well, ensuring that the type matches
@@ -241,10 +243,12 @@ async function getSchema<T extends Schema.SchemaKey>(
 			value = await configJsonBackend.get(key);
 			break;
 		case 'db':
+			{
 				const [conf] = await $db('config').select('value').where({ key });
 				if (conf != null) {
 					return conf.value;
 				}
+			}
 			break;
 	}
 
@@ -265,7 +269,7 @@ function validateConfigMap<T extends SchemaTypeKey>(
 	// throw if any value fails verification
 	return _.mapValues(configMap, (value, key) => {
 		if (
-			!Schema.schema.hasOwnProperty(key) ||
+			!Object.prototype.hasOwnProperty.call(Schema.schema, key) ||
 			!Schema.schema[key as Schema.SchemaKey].mutable
 		) {
 			throw new Error(

src/config/types.ts

@@ -54,12 +54,13 @@ export const PermissiveNumber = new t.Type<number, string | number>(
 			switch (typeof v) {
 				case 'number':
 					return t.success(v);
-				case 'string':
+				case 'string': {
 					const i = parseInt(v, 10);
 					if (Number.isNaN(i)) {
 						return t.failure(v, c);
 					}
 					return t.success(i);
+				}
 				default:
 					return t.failure(v, c);
 			}
@@ -73,7 +74,7 @@ export const PermissiveNumber = new t.Type<number, string | number>(
 
 // Define this differently, so that we can add a generic to it
 export class StringJSON<T> extends t.Type<T, string> {
-	public readonly _tag: 'StringJSON' = 'StringJSON';
+	public readonly _tag: 'StringJSON' = 'StringJSON' as const;
 	constructor(type: t.InterfaceType<any>) {
 		super(
 			'StringJSON',

src/config/utils.ts

@@ -4,9 +4,9 @@ import * as Bluebird from 'bluebird';
 import * as config from '../config';
 import * as constants from '../lib/constants';
 import { getMetaOSRelease } from '../lib/os-release';
-import { EnvVarObject } from '../types';
+import type { EnvVarObject } from '../types';
 import { allBackends as Backends } from './backends';
-import { ConfigOptions, ConfigBackend } from './backends/backend';
+import type { ConfigOptions, ConfigBackend } from './backends/backend';
 
 export async function getSupportedBackends(): Promise<ConfigBackend[]> {
 	// Get required information to find supported backends

src/db.ts

@@ -1,4 +1,5 @@
-import { knex, Knex } from 'knex';
+import type { Knex } from 'knex';
+import { knex } from 'knex';
 import * as path from 'path';
 import * as _ from 'lodash';
 

src/device-api/actions.ts

@@ -8,10 +8,8 @@ import * as logger from '../logger';
 import * as config from '../config';
 import * as hostConfig from '../host-config';
 import * as applicationManager from '../compose/application-manager';
-import {
+import type { CompositionStepAction } from '../compose/composition-steps';
-	CompositionStepAction,
+import { generateStep } from '../compose/composition-steps';
-	generateStep,
-} from '../compose/composition-steps';
 import * as commitStore from '../compose/commit';
 import { getApp } from '../device-state/db-format';
 import * as TargetState from '../device-state/target-state';

src/device-api/api-keys.ts

@@ -1,5 +1,5 @@
 import * as _ from 'lodash';
-import * as express from 'express';
+import type * as express from 'express';
 import * as memoizee from 'memoizee';
 import { TypedError } from 'typed-error';
 
@@ -37,7 +37,7 @@ type ScopeCheckCollection = {
  * The scopes which a key can cover.
  */
 type ScopeTypes = {
-	global: {};
+	global: NonNullable<unknown>;
 	app: {
 		appId: number;
 	};
@@ -222,11 +222,11 @@ async function generateKey(
 		// remove the cached lookup for the key
 		const [apiKey] = secrets;
 		if (apiKey != null) {
-			getApiKeyByKey.clear(apiKey.key);
+			await getApiKeyByKey.clear(apiKey.key);
 		}
 
 		// remove the cached value for this lookup
-		getApiKeyForService.clear(appId, serviceName);
+		await getApiKeyForService.clear(appId, serviceName);
 
 		// return a new API key
 		return await createNewKey(appId, serviceName, scopes);

src/device-api/index.ts

@@ -100,9 +100,11 @@ export class SupervisorAPI {
 						log.error('Failed to stop Supervisor API');
 						return reject(err);
 					}
-					options?.errored
+					if (options?.errored) {
-						? log.error('Stopped Supervisor API')
+						log.error('Stopped Supervisor API');
-						: log.info('Stopped Supervisor API');
+					} else {
+						log.info('Stopped Supervisor API');
+					}
 					return resolve();
 				});
 			});

src/device-api/middleware/logging.ts

@@ -1,5 +1,5 @@
 import * as morgan from 'morgan';
-import { Request } from 'express';
+import type { Request } from 'express';
 
 import log from '../../lib/supervisor-console';
 

src/device-api/v1.ts

@@ -1,11 +1,10 @@
 import * as express from 'express';
-import * as _ from 'lodash';
 import type { Response } from 'express';
 
 import * as actions from './actions';
-import { AuthorizedRequest } from './api-keys';
+import type { AuthorizedRequest } from './api-keys';
 import * as eventTracker from '../event-tracker';
-import * as deviceState from '../device-state';
+import type * as deviceState from '../device-state';
 
 import * as constants from '../lib/constants';
 import { checkInt, checkTruthy } from '../lib/validation';
@@ -15,7 +14,7 @@ import {
 	isBadRequestError,
 	UpdatesLockedError,
 } from '../lib/errors';
-import { CompositionStepAction } from '../compose/composition-steps';
+import type { CompositionStepAction } from '../compose/composition-steps';
 
 const disallowedHostConfigPatchFields = ['local_ip', 'local_port'];
 

src/device-api/v2.ts

@@ -5,8 +5,8 @@ import * as _ from 'lodash';
 import * as deviceState from '../device-state';
 import * as apiBinder from '../api-binder';
 import * as applicationManager from '../compose/application-manager';
-import { CompositionStepAction } from '../compose/composition-steps';
+import type { CompositionStepAction } from '../compose/composition-steps';
-import { Service } from '../compose/service';
+import type { Service } from '../compose/service';
 import Volume from '../compose/volume';
 import * as commitStore from '../compose/commit';
 import * as config from '../config';
@@ -26,7 +26,7 @@ import {
 	BadRequestError,
 } from '../lib/errors';
 import { isVPNActive } from '../network';
-import { AuthorizedRequest } from './api-keys';
+import type { AuthorizedRequest } from './api-keys';
 import { fromV2TargetState } from '../lib/legacy';
 import * as actions from './actions';
 import { v2ServiceEndpointError } from './messages';

src/device-config.ts

@@ -6,14 +6,14 @@ import * as config from './config';
 import * as db from './db';
 import * as logger from './logger';
 import * as dbus from './lib/dbus';
-import { EnvVarObject } from './types';
+import type { EnvVarObject } from './types';
 import { UnitNotLoadedError } from './lib/errors';
 import { checkInt, checkTruthy } from './lib/validation';
 import log from './lib/supervisor-console';
 import * as configUtils from './config/utils';
-import { SchemaTypeKey } from './config/schema-type';
+import type { SchemaTypeKey } from './config/schema-type';
 import { matchesAnyBootConfig } from './config/backends';
-import { ConfigBackend } from './config/backends/backend';
+import type { ConfigBackend } from './config/backends/backend';
 import { Odmdata } from './config/backends/odmdata';
 import * as fsUtils from './lib/fs-utils';
 import { pathOnRoot } from './lib/host-utils';
@@ -627,6 +627,7 @@ function changeRequired(
 					// Set changeRequired to false so we do not get stuck in a loop trying to fix this mismatch
 					aChangeIsRequired = false;
 				}
+				throw e;
 			default:
 				throw e;
 		}

src/device-state.ts

@@ -2,7 +2,7 @@ import * as Bluebird from 'bluebird';
 import { stripIndent } from 'common-tags';
 import { EventEmitter } from 'events';
 import * as _ from 'lodash';
-import StrictEventEmitter from 'strict-event-emitter-types';
+import type StrictEventEmitter from 'strict-event-emitter-types';
 import { isRight } from 'fp-ts/lib/Either';
 import Reporter from 'io-ts-reporters';
 import prettyMs = require('pretty-ms');
@@ -31,14 +31,14 @@ import { loadTargetFromFile } from './device-state/preload';
 import * as applicationManager from './compose/application-manager';
 import * as commitStore from './compose/commit';
 
-import {
+import type {
 	DeviceLegacyState,
 	InstancedDeviceState,
-	TargetState,
 	DeviceState,
 	DeviceReport,
 	AppState,
 } from './types';
+import { TargetState } from './types';
 import type {
 	CompositionStepT,
 	CompositionStepAction,
@@ -85,11 +85,11 @@ type DeviceStateEventEmitter = StrictEventEmitter<
 	DeviceStateEvents
 >;
 const events = new EventEmitter() as DeviceStateEventEmitter;
-export const on: typeof events['on'] = events.on.bind(events);
+export const on: (typeof events)['on'] = events.on.bind(events);
-export const once: typeof events['once'] = events.once.bind(events);
+export const once: (typeof events)['once'] = events.once.bind(events);
-export const removeListener: typeof events['removeListener'] =
+export const removeListener: (typeof events)['removeListener'] =
 	events.removeListener.bind(events);
-export const removeAllListeners: typeof events['removeAllListeners'] =
+export const removeAllListeners: (typeof events)['removeAllListeners'] =
 	events.removeAllListeners.bind(events);
 
 export type DeviceStateStepTarget = 'reboot' | 'shutdown' | 'noop';
@@ -194,9 +194,13 @@ export async function initNetworkChecks({
 	apiEndpoint: config.ConfigType<'apiEndpoint'>;
 	connectivityCheckEnabled: config.ConfigType<'connectivityCheckEnabled'>;
 }) {
-	network.startConnectivityCheck(apiEndpoint, connectivityCheckEnabled, (c) => {
+	await network.startConnectivityCheck(
+		apiEndpoint,
+		connectivityCheckEnabled,
+		(c) => {
 			connected = c;
-	});
+		},
+	);
 	config.on('change', function (changedConfig) {
 		if (changedConfig.connectivityCheckEnabled != null) {
 			network.enableConnectivityCheck(changedConfig.connectivityCheckEnabled);
@@ -240,7 +244,7 @@ export async function loadInitialState() {
 	]);
 	maxPollTime = conf.appUpdatePollInterval;
 
-	initNetworkChecks(conf);
+	await initNetworkChecks(conf);
 
 	if (!conf.initialConfigSaved) {
 		await saveInitialConfig();
@@ -851,8 +855,8 @@ export function triggerApplyTarget({
 	}
 	applyCancelled = false;
 	applyInProgress = true;
-	new Promise((resolve, reject) => {
+	void new Promise((resolve, reject) => {
-		setTimeout(delay).then(resolve);
+		void setTimeout(delay).then(resolve);
 		cancelDelay = reject;
 	})
 		.catch(() => {

src/device-state/db-format.ts

@@ -1,13 +1,13 @@
 import * as _ from 'lodash';
 
-import * as db from '../db';
+import type * as db from '../db';
 import * as targetStateCache from './target-state-cache';
-import { DatabaseApp, DatabaseService } from './target-state-cache';
+import type { DatabaseApp, DatabaseService } from './target-state-cache';
 
 import App from '../compose/app';
 import * as images from '../compose/images';
 
-import {
+import type {
 	InstancedAppState,
 	TargetApp,
 	TargetApps,

src/device-state/legacy.ts

@@ -1,6 +1,7 @@
 import * as _ from 'lodash';
-import { fromV2TargetApps, TargetAppsV2 } from '../lib/legacy';
+import type { TargetAppsV2 } from '../lib/legacy';
-import { AppsJsonFormat, TargetApp, TargetRelease } from '../types';
+import { fromV2TargetApps } from '../lib/legacy';
+import type { AppsJsonFormat, TargetApp, TargetRelease } from '../types';
 
 /**
  * Converts a single app from single container format into

src/device-state/preload.ts

@@ -1,7 +1,8 @@
 import * as _ from 'lodash';
 import { promises as fs } from 'fs';
 
-import { Image, imageFromService } from '../compose/images';
+import type { Image } from '../compose/images';
+import { imageFromService } from '../compose/images';
 import { NumericIdentifier } from '../types';
 import * as deviceState from '../device-state';
 import * as config from '../config';

src/device-state/target-state-cache.ts

@@ -2,7 +2,7 @@ import * as _ from 'lodash';
 
 import * as config from '../config';
 import * as db from '../db';
-import { TargetAppClass } from '../types';
+import type { TargetAppClass } from '../types';
 
 // We omit the id (which does appear in the db) in this type, as we don't use it
 // at all, and we can use the below type for both insertion and retrieval.

src/device-state/target-state.ts

@@ -1,7 +1,6 @@
 import { EventEmitter } from 'events';
 import * as url from 'url';
 import { setTimeout } from 'timers/promises';
-import * as _ from 'lodash';
 import * as Bluebird from 'bluebird';
 import type StrictEventEmitter from 'strict-event-emitter-types';
 

src/event-bus.ts

@@ -1,7 +1,7 @@
 import { EventEmitter } from 'events';
 import * as _ from 'lodash';
-import StrictEventEmitter from 'strict-event-emitter-types';
+import type StrictEventEmitter from 'strict-event-emitter-types';
-import { TargetState } from './types/state';
+import type { TargetState } from './types/state';
 
 export interface GlobalEvents {
 	deviceProvisioned: void;
@@ -10,10 +10,6 @@ export interface GlobalEvents {
 
 type GlobalEventEmitter = StrictEventEmitter<EventEmitter, GlobalEvents>;
 
-export class GlobalEventBus extends (EventEmitter as new () => GlobalEventEmitter) {
+export const getInstance = _.once(
-	public constructor() {
+	() => new EventEmitter() as GlobalEventEmitter,
-		super();
+);
-	}
-}
-
-export const getInstance = _.once(() => new GlobalEventBus());

src/event-tracker.ts

@@ -1,6 +1,4 @@
 import mask = require('json-mask');
-import * as _ from 'lodash';
-
 import log from './lib/supervisor-console';
 
 export type EventTrackProperties = Dictionary<any>;
@@ -16,7 +14,7 @@ const mixpanelMask = [
 	'stateDiff/local(os_version,supervisor_version,ip_address,apps/*/services)',
 ].join(',');
 
-export async function track(
+export function track(
 	event: string,
 	properties: EventTrackProperties | Error = {},
 ) {
@@ -34,6 +32,6 @@ export async function track(
 	}
 
 	// Don't send potentially sensitive information, by using a whitelist
-	properties = mask(properties, mixpanelMask);
+	properties = mask(properties, mixpanelMask) || {};
 	log.event('Event:', event, JSON.stringify(properties));
 }

src/lib/api-helper.ts

@@ -1,4 +1,4 @@
-import { PinejsClientRequest } from 'pinejs-client-request';
+import type { PinejsClientRequest } from 'pinejs-client-request';
 
 import * as Bluebird from 'bluebird';
 import * as config from '../config';

src/lib/avahi.ts

@@ -10,7 +10,7 @@ export const initialized = _.once(async () => {
 
 	config.on('change', (conf) => {
 		if (conf.hostDiscoverability != null) {
-			switchDiscoverability(conf.hostDiscoverability);
+			void switchDiscoverability(conf.hostDiscoverability);
 		}
 	});
 

src/lib/contracts.ts

@@ -7,7 +7,7 @@ import { Blueprint, Contract, ContractObject } from '@balena/contrato';
 
 import { ContractValidationError, InternalInconsistencyError } from './errors';
 import { checkTruthy } from './validation';
-import { TargetApps } from '../types';
+import type { TargetApps } from '../types';
 
 export { ContractObject };
 

src/lib/conversions.ts

@@ -1,6 +1,6 @@
 import * as _ from 'lodash';
 
-import { EnvVarObject } from '../types';
+import type { EnvVarObject } from '../types';
 
 import log from '../lib/supervisor-console';
 

src/lib/docker-utils.ts

@@ -1,4 +1,5 @@
-import { DockerProgress, ProgressCallback } from 'docker-progress';
+import type { ProgressCallback } from 'docker-progress';
+import { DockerProgress } from 'docker-progress';
 import * as Dockerode from 'dockerode';
 import * as _ from 'lodash';
 import * as memoizee from 'memoizee';
@@ -6,7 +7,7 @@ import * as memoizee from 'memoizee';
 import { applyDelta, OutOfSyncError } from 'docker-delta';
 import DockerToolbelt = require('docker-toolbelt');
 
-import { SchemaReturn } from '../config/schema-type';
+import type { SchemaReturn } from '../config/schema-type';
 import { envArrayToObject } from './conversions';
 import {
 	DeltaStillProcessingError,
@@ -14,7 +15,7 @@ import {
 	InvalidNetGatewayError,
 } from './errors';
 import * as request from './request';
-import { EnvVarObject } from '../types';
+import type { EnvVarObject } from '../types';
 
 import log from './supervisor-console';
 
@@ -191,6 +192,8 @@ export async function fetchDeltaWithProgress(
 						`Got ${res.statusCode} when requesting an image from delta server.`,
 					);
 				}
+				{
+					// lexical declarations inside a case clause need to be wrapped in a block
 					const deltaUrl = res.headers['location'];
 					const deltaSrc = deltaSourceId;
 					const resumeOpts = {
@@ -206,6 +209,7 @@ export async function fetchDeltaWithProgress(
 						onProgress,
 						logFn,
 					);
+				}
 				break;
 			case 3:
 				if (res.statusCode !== 200) {
@@ -213,6 +217,8 @@ export async function fetchDeltaWithProgress(
 						`Got ${res.statusCode} when requesting v3 delta from delta server.`,
 					);
 				}
+				{
+					// lexical declarations inside a case clause need to be wrapped in a block
 					let name;
 					try {
 						name = JSON.parse(data).name;
@@ -222,6 +228,7 @@ export async function fetchDeltaWithProgress(
 						);
 					}
 					id = await applyBalenaDelta(name, token, onProgress, logFn);
+				}
 				break;
 			default:
 				throw new Error(`Unsupported delta version: ${deltaOpts.deltaVersion}`);
@@ -295,7 +302,7 @@ export async function getNetworkGateway(networkName: string): Promise<string> {
 	);
 }
 
-function applyRsyncDelta(
+async function applyRsyncDelta(
 	imgSrc: string,
 	deltaUrl: string,
 	applyTimeout: number,
@@ -305,8 +312,8 @@ function applyRsyncDelta(
 ): Promise<string> {
 	logFn(`Applying rsync delta: ${deltaUrl}`);
 
-	return new Promise(async (resolve, reject) => {
 	const resumable = await request.getResumableRequest();
+	return new Promise((resolve, reject) => {
 		const req = resumable(Object.assign({ url: deltaUrl }, opts));
 		req
 			.on('progress', onProgress)

src/lib/firewall.ts

@@ -15,7 +15,7 @@ export const initialised = _.once(async () => {
 	// apply firewall whenever relevant config changes occur...
 	config.on('change', ({ firewallMode, localMode }) => {
 		if (firewallMode || localMode != null) {
-			applyFirewall({ firewallMode, localMode });
+			void applyFirewall({ firewallMode, localMode });
 		}
 	});
 });

src/lib/fs-utils.ts

@@ -1,4 +1,3 @@
-import * as _ from 'lodash';
 import { promises as fs } from 'fs';
 import * as path from 'path';
 import { exec as execSync } from 'child_process';

src/lib/host-utils.ts

@@ -5,7 +5,7 @@ import { exec, exists } from './fs-utils';
 
 function withBase(base: string) {
 	function withPath(): string;
-	function withPath(path: string): string;
+	function withPath(singlePath: string): string;
 	function withPath(...paths: string[]): string[];
 	function withPath(...paths: string[]): string[] | string {
 		if (arguments.length === 0) {
@@ -42,7 +42,10 @@ export const pathExistsOnState = async (p: string) =>
 	await exists(pathOnState(p));
 
 class CodedError extends Error {
-	constructor(msg: string, readonly code: number | string) {
+	constructor(
+		msg: string,
+		readonly code: number | string,
+	) {
 		super(msg);
 	}
 }

src/lib/iptables.ts

@@ -7,7 +7,10 @@ import { exec } from './fs-utils';
 import log from './supervisor-console';
 
 export class IPTablesRuleError extends TypedError {
-	public constructor(err: string | Error, public ruleset: string) {
+	public constructor(
+		err: string | Error,
+		public ruleset: string,
+	) {
 		super(err);
 	}
 }

src/lib/journald.ts

@@ -1,4 +1,5 @@
-import { ChildProcess, spawn } from 'child_process';
+import type { ChildProcess } from 'child_process';
+import { spawn } from 'child_process';
 
 import log from './supervisor-console';
 

src/lib/json.ts

@@ -30,7 +30,7 @@ export function equals<T>(value: T, other: T): boolean {
  * Returns true if the the object equals `{}` or is an empty
  * array
  */
-export function empty<T extends {}>(value: T): boolean {
+export function empty<T extends object>(value: T): boolean {
 	return (Array.isArray(value) && value.length === 0) || equals(value, {});
 }
 

src/lib/legacy.ts

@@ -1,5 +1,3 @@
-import * as _ from 'lodash';
-
 import * as path from 'path';
 import * as apiBinder from '../api-binder';
 import * as config from '../config';
@@ -16,14 +14,14 @@ import {
 import { docker } from './docker-utils';
 import { log } from './supervisor-console';
 import { pathOnData } from './host-utils';
-import Volume from '../compose/volume';
+import type Volume from '../compose/volume';
 import * as logger from '../logger';
 import type {
 	DatabaseApp,
 	DatabaseService,
 } from '../device-state/target-state-cache';
 
-import { TargetApp, TargetApps, TargetState } from '../types';
+import type { TargetApp, TargetApps, TargetState } from '../types';
 
 const defaultLegacyVolume = () => 'resin-data';
 

src/lib/migration.ts

@@ -1,10 +1,9 @@
-import * as _ from 'lodash';
 import { promises as fs } from 'fs';
 import * as path from 'path';
 
 import * as volumeManager from '../compose/volume-manager';
 import * as deviceState from '../device-state';
-import { TargetState } from '../types';
+import type { TargetState } from '../types';
 import * as constants from './constants';
 import { BackupError, isNotFoundError } from './errors';
 import { exec, exists, mkdirp, unlinkAll } from './fs-utils';
@@ -24,15 +23,18 @@ export async function loadBackupFromMigration(
 
 		await deviceState.setTarget(targetState);
 
-		// TODO: this code is only single-app compatible
+		// Assume there is only a single device in the target state
-		const [uuid] = Object.keys(targetState.local?.apps);
+		const [localDevice] = Object.values(targetState);
 
-		if (!!uuid) {
+		// TODO: this code is only single-app compatible
+		const [uuid] = Object.keys(localDevice?.apps);
+
+		if (uuid) {
 			throw new BackupError('No apps in the target state');
 		}
 
-		const { id: appId } = targetState.local?.apps[uuid];
+		const { id: appId } = localDevice.apps[uuid];
-		const [release] = Object.values(targetState.local?.apps[uuid].releases);
+		const [release] = Object.values(localDevice.apps[uuid].releases);
 
 		const volumes = release?.volumes ?? {};
 

src/lib/register-device.ts

@@ -4,7 +4,7 @@ import { getRequestInstance } from './request';
 
 export const { generateUniqueKey, register } = getRegisterDevice({
 	request: {
-		send: async (options: {}) => {
+		send: async (options: object) => {
 			const request = await getRequestInstance();
 			const [response] = await request.postAsync({ ...options, json: true });
 			return response;

src/lib/supervisor-console.ts

@@ -1,5 +1,5 @@
 import * as _ from 'lodash';
-import { TransformableInfo } from 'logform';
+import type { TransformableInfo } from 'logform';
 import * as winston from 'winston';
 
 const levels = {

src/lib/update-lock.ts

@@ -1,5 +1,4 @@
 import * as Bluebird from 'bluebird';
-import * as _ from 'lodash';
 import { promises as fs } from 'fs';
 import * as path from 'path';
 import * as Lock from 'rwlock';
@@ -92,7 +91,7 @@ async function dispose(
  * TODO: Remove skipLock as it's not a good interface. If lock is called it should try to take the lock
  * without an option to skip.
  */
-export async function lock<T extends unknown>(
+export async function lock<T>(
 	appId: number | number[],
 	{ force = false, skipLock = false }: { force: boolean; skipLock?: boolean },
 	fn: () => Resolvable<T>,

src/local-mode.ts

@@ -171,13 +171,13 @@ export class LocalModeManager {
 						e.message,
 					);
 					return this.collectContainerResources(fallback);
-				} catch (e: any) {
+				} catch (err: any) {
 					// Inspect operation fails (using legacy container name?).
 					const fallback = SUPERVISOR_LEGACY_CONTAINER_NAME_FALLBACK;
 					log.warn(
 						'Supervisor container resources cannot be obtained by container ID. ' +
 							`Using '${fallback}' name instead.`,
-						e.message,
+						err.message,
 					);
 					return this.collectContainerResources(fallback);
 				}

src/logger.ts

@@ -4,15 +4,12 @@ import * as _ from 'lodash';
 import * as config from './config';
 import * as db from './db';
 import * as eventTracker from './event-tracker';
-import { LogType } from './lib/log-types';
+import type { LogType } from './lib/log-types';
 import { writeLock } from './lib/update-lock';
-import {
+import type { LogBackend, LogMessage } from './logging';
-	BalenaLogBackend,
+import { BalenaLogBackend, LocalLogBackend } from './logging';
-	LocalLogBackend,
+import type { MonitorHook } from './logging/monitor';
-	LogBackend,
+import logMonitor from './logging/monitor';
-	LogMessage,
-} from './logging';
-import logMonitor, { MonitorHook } from './logging/monitor';
 
 import * as globalEventBus from './event-bus';
 import superConsole from './lib/supervisor-console';

src/logging/balena-backend.ts

@@ -1,11 +1,12 @@
-import { ClientRequest } from 'http';
+import type { ClientRequest } from 'http';
 import * as https from 'https';
 import * as _ from 'lodash';
 import * as stream from 'stream';
 import * as url from 'url';
 import * as zlib from 'zlib';
 
-import { LogBackend, LogMessage } from './log-backend';
+import type { LogMessage } from './log-backend';
+import { LogBackend } from './log-backend';
 
 import log from '../lib/supervisor-console';
 

src/logging/local-backend.ts

@@ -2,7 +2,8 @@ import * as _ from 'lodash';
 
 import { Readable } from 'stream';
 import { checkInt } from '../lib/validation';
-import { LogBackend, LogMessage } from './log-backend';
+import type { LogMessage } from './log-backend';
+import { LogBackend } from './log-backend';
 
 import log from '../lib/supervisor-console';
 

src/logging/monitor.ts

@@ -183,7 +183,10 @@ class LogMonitor {
 		const isStdErr = row.PRIORITY === '3';
 		const timestamp = Math.floor(Number(row.__REALTIME_TIMESTAMP) / 1000); // microseconds to milliseconds
 		this.updateContainerSentTimestamp(containerId, timestamp);
-		this.containers[containerId].hook({ message, isStdErr, timestamp });
+
+		// WARNING: this could lead to a memory leak as the hook is not being awaited
+		// and the journal can be very verbose
+		void this.containers[containerId].hook({ message, isStdErr, timestamp });
 	}
 
 	private updateContainerSentTimestamp(

src/migrations/20171129013519_legacy.js

@@ -89,7 +89,7 @@ exports.up = function (knex) {
 					addColumn('app', 'markedForDeletion', 'boolean'),
 					dropColumn('app', 'containerId'),
 				]).then(() => {
-					//When updating from older supervisors, config can be null
+					// When updating from older supervisors, config can be null
 					return knex('app')
 						.update({ config: '{}' })
 						.whereNull('config')

src/migrations/20171129064057_multicontainer.js

@@ -1,7 +1,7 @@
-const Bluebird = require('bluebird');
+import * as Bluebird from 'bluebird';
-const _ = require('lodash');
+import * as _ from 'lodash';
 
-var tryParse = function (obj) {
+const tryParse = function (obj) {
 	try {
 		return JSON.parse(obj);
 	} catch {
@@ -9,14 +9,14 @@ var tryParse = function (obj) {
 	}
 };
 
-var singleToMulticontainerApp = function (app) {
+const singleToMulticontainerApp = function (app) {
 	// From *very* old supervisors, env or config may be null
 	// so we ignore errors parsing them
 	const conf = tryParse(app.config);
 	const env = tryParse(app.env);
 	const environment = {};
 	const appId = parseInt(app.appId, 10);
-	for (let key in env) {
+	for (const key in env) {
 		if (!/^RESIN_/.test(key)) {
 			environment[key] = env[key];
 		}
@@ -68,7 +68,7 @@ var singleToMulticontainerApp = function (app) {
 	return newApp;
 };
 
-var jsonifyAppFields = function (app) {
+const jsonifyAppFields = function (app) {
 	const newApp = _.clone(app);
 	newApp.services = JSON.stringify(app.services);
 	newApp.networks = JSON.stringify(app.networks);
@@ -76,7 +76,7 @@ var jsonifyAppFields = function (app) {
 	return newApp;
 };
 
-var imageForApp = function (app) {
+const imageForApp = function (app) {
 	const service = app.services[0];
 	return {
 		name: service.image,
@@ -89,7 +89,7 @@ var imageForApp = function (app) {
 	};
 };
 
-var imageForDependentApp = function (app) {
+const imageForDependentApp = function (app) {
 	return {
 		name: app.image,
 		appId: app.appId,

src/migrations/20180516164000-endpoint-specific-apps.js

@@ -1,4 +1,4 @@
-const fs = require('fs');
+import * as fs from 'fs';
 const configJsonPath = process.env.CONFIG_MOUNT_POINT;
 
 exports.up = function (knex) {

src/migrations/20181907164000-endpoint-specific-logschannel.js

@@ -1,5 +1,5 @@
-const Bluebird = require('bluebird');
+import * as Bluebird from 'bluebird';
-const fs = require('fs');
+import * as fs from 'fs';
 const configJsonPath = process.env.CONFIG_MOUNT_POINT;
 
 exports.up = function (knex) {

src/migrations/M00000.js

@@ -1,4 +1,4 @@
-const _ = require('lodash');
+import * as _ from 'lodash';
 
 // We take legacy deviceConfig targets and store them without the RESIN_ prefix
 // (we also strip the BALENA_ prefix for completeness, even though no supervisors

src/migrations/M00001.js

@@ -1,7 +1,7 @@
-const fs = require('fs');
+import * as fs from 'fs';
 const configJsonPath = process.env.CONFIG_MOUNT_POINT;
 
-const { checkTruthy } = require('../lib/validation');
+import { checkTruthy } from '../lib/validation';
 
 exports.up = function (knex) {
 	return knex('config')

src/migrations/M00002.js

@@ -1,7 +1,7 @@
-const fs = require('fs');
+import * as fs from 'fs';
 const configJsonPath = process.env.CONFIG_MOUNT_POINT;
 
-const { checkTruthy } = require('../lib/validation');
+import { checkTruthy } from '../lib/validation';
 
 exports.up = function (knex) {
 	return new Promise((resolve) => {

src/network.ts

@@ -80,7 +80,7 @@ export const startConnectivityCheck = _.once(
 		watch(constants.vpnStatusPath, vpnStatusInotifyCallback);
 
 		if (enable) {
-			vpnStatusInotifyCallback();
+			void vpnStatusInotifyCallback();
 		}
 
 		const parsedUrl = url.parse(apiEndpoint);

src/supervisor.ts

@@ -72,8 +72,8 @@ export class Supervisor {
 					routers: [v1.router, v2.router],
 					healthchecks: [apiBinder.healthcheck, deviceState.healthcheck],
 				});
-				this.api.listen(conf.listenPort, conf.apiTimeout);
 				deviceState.on('shutdown', () => this.api.stop());
+				return this.api.listen(conf.listenPort, conf.apiTimeout);
 			})(),
 			apiBinder.start(),
 		]);

src/types/basic.ts

@@ -1,5 +1,6 @@
 import * as t from 'io-ts';
-import { chain, fold, isRight, left, right, Either } from 'fp-ts/lib/Either';
+import type { Either } from 'fp-ts/lib/Either';
+import { chain, fold, isRight, left, right } from 'fp-ts/lib/Either';
 import { pipe, flow } from 'fp-ts/lib/function';
 
 /**
@@ -154,7 +155,7 @@ export type LabelObject = t.TypeOf<typeof LabelObject>;
 // Valid docker container and volume name according to
 // https://github.com/moby/moby/blob/04c6f09fbdf60c7765cc4cb78883faaa9d971fa5/daemon/daemon.go#L56
 // [a-zA-Z0-9][a-zA-Z0-9_.-]
-const DOCKER_NAME_REGEX = /^[a-zA-Z0-9][a-zA-Z0-9_\.\-]*$/;
+const DOCKER_NAME_REGEX = /^[a-zA-Z0-9][a-zA-Z0-9_.-]*$/;
 export const DockerName = shortStringWithRegex(
 	'LabelName',
 	DOCKER_NAME_REGEX,

src/types/state.ts

@@ -1,8 +1,8 @@
 import * as t from 'io-ts';
 
 // TODO: move all these exported types to ../compose/types
-import { ComposeNetworkConfig } from '../compose/types/network';
+import type { ComposeNetworkConfig } from '../compose/types/network';
-import { ComposeVolumeConfig } from '../compose/volume';
+import type { ComposeVolumeConfig } from '../compose/volume';
 
 import {
 	DockerName,
@@ -15,7 +15,7 @@ import {
 	nonEmptyRecord,
 } from './basic';
 
-import App from '../compose/app';
+import type App from '../compose/app';
 
 export type DeviceLegacyReport = Partial<{
 	api_port: number;
@@ -105,7 +105,7 @@ const fromType = <T extends object>(name: string) =>
 // Alias short string to UUID so code reads more clearly
 export const UUID = ShortString;
 
-/*****************
+/** ***************
  * Current state *
  *****************/
 const ServiceState = t.intersection([
@@ -176,7 +176,7 @@ export const DeviceState = t.record(
 );
 export type DeviceState = t.TypeOf<typeof DeviceState>;
 
-/****************
+/** **************
  * Target state *
  ****************/
 /**

test/integration/compose/application-manager.spec.ts

@@ -18,7 +18,7 @@ import {
 	expectSteps,
 	expectNoStep,
 } from '~/test-lib/state-helper';
-import { InstancedAppState } from '~/src/types';
+import type { InstancedAppState } from '~/src/types';
 
 // TODO: application manager inferNextSteps still queries some stuff from
 // the engine instead of receiving that information as parameter. Refactoring

test/integration/compose/service.spec.ts

@@ -1,5 +1,3 @@
-import * as _ from 'lodash';
-
 import { expect } from 'chai';
 
 import Service from '~/src/compose/service';

test/integration/compose/volume.spec.ts

@@ -1,5 +1,6 @@
 import { expect } from 'chai';
-import { SinonStub, stub } from 'sinon';
+import type { SinonStub } from 'sinon';
+import { stub } from 'sinon';
 import Volume from '~/src/compose/volume';
 import * as logTypes from '~/lib/log-types';
 import * as logger from '~/src/logger';

test/integration/config.spec.ts

@@ -1,14 +1,15 @@
-import * as _ from 'lodash';
 import { promises as fs } from 'fs';
-import { SinonSpy, spy, stub } from 'sinon';
+import type { SinonSpy } from 'sinon';
+import { spy, stub } from 'sinon';
 import { expect } from 'chai';
-import { testfs, TestFs } from 'mocha-pod';
+import type { TestFs } from 'mocha-pod';
+import { testfs } from 'mocha-pod';
 
 import { fnSchema } from '~/src/config/functions';
 import * as hostUtils from '~/lib/host-utils';
 import { configJsonPath } from '~/lib/constants';
 
-// Utility method to use along with `require`
+// Utility type to use along with `require`
 type Config = typeof import('~/src/config');
 
 describe('config', () => {
@@ -35,6 +36,7 @@ describe('config', () => {
 	});
 
 	it('reads and exposes values from config.json', async () => {
+		// eslint-disable-next-line
 		const config = require('~/src/config') as Config;
 		await config.initialized();
 		const configJson = await readConfigJson();
@@ -43,6 +45,7 @@ describe('config', () => {
 	});
 
 	it('allows reading several values in one getMany call', async () => {
+		// eslint-disable-next-line
 		const config = require('~/src/config') as Config;
 		await config.initialized();
 		const configJson = await readConfigJson();
@@ -55,6 +58,7 @@ describe('config', () => {
 	});
 
 	it('generates a uuid and stores it in config.json', async () => {
+		// eslint-disable-next-line
 		const config = require('~/src/config') as Config;
 		await config.initialized();
 		const configJson = await readConfigJson();
@@ -65,6 +69,7 @@ describe('config', () => {
 	});
 
 	it('does not allow setting an immutable field', async () => {
+		// eslint-disable-next-line
 		const config = require('~/src/config') as Config;
 		await config.initialized();
 		return expect(config.set({ deviceType: 'a different device type' })).to.be
@@ -72,6 +77,7 @@ describe('config', () => {
 	});
 
 	it('allows setting both config.json and database fields transparently', async () => {
+		// eslint-disable-next-line
 		const config = require('~/src/config') as Config;
 		await config.initialized();
 		await config.set({
@@ -86,6 +92,7 @@ describe('config', () => {
 	});
 
 	it('allows deleting a config.json key and returns a default value if none is set', async () => {
+		// eslint-disable-next-line
 		const config = require('~/src/config') as Config;
 		await config.initialized();
 		await config.remove('appUpdatePollInterval');
@@ -94,6 +101,7 @@ describe('config', () => {
 	});
 
 	it('allows deleting a config.json key if it is null', async () => {
+		// eslint-disable-next-line
 		const config = require('~/src/config') as Config;
 		await config.initialized();
 		await config.set({ apiKey: null });
@@ -107,6 +115,7 @@ describe('config', () => {
 	});
 
 	it('does not allow modifying or removing a function value', async () => {
+		// eslint-disable-next-line
 		const config = require('~/src/config') as Config;
 		await config.initialized();
 		// We have to cast to any below, as the type system will
@@ -116,19 +125,19 @@ describe('config', () => {
 	});
 
 	it('throws when asked for an unknown key', async () => {
+		// eslint-disable-next-line
 		const config = require('~/src/config') as Config;
 		await config.initialized();
 		await expect(config.get('unknownInvalidValue' as any)).to.be.rejected;
 	});
 
 	it('emits a change event when values change', async () => {
+		// eslint-disable-next-line
 		const config = require('~/src/config') as Config;
 		await config.initialized();
 		const listener = stub();
 		config.on('change', listener);
-		config.set({ name: 'someValue' });
+		await config.set({ name: 'someValue' });
-
-		await new Promise((resolve) => setTimeout(resolve, 1000));
 
 		expect(listener).to.have.been.calledWith({ name: 'someValue' });
 	});
@@ -149,6 +158,7 @@ describe('config', () => {
 			),
 		}).enable();
 
+		// eslint-disable-next-line
 		const config = require('~/src/config') as Config;
 		await config.initialized();
 		await config.set({ developmentMode: false });
@@ -160,6 +170,7 @@ describe('config', () => {
 	});
 
 	it('reads and exposes MAC addresses', async () => {
+		// eslint-disable-next-line
 		const config = require('~/src/config') as Config;
 		await config.initialized();
 		const macAddress = await config.get('macAddress');
@@ -168,12 +179,14 @@ describe('config', () => {
 
 	describe('Function config providers', () => {
 		it('should throw if a non-mutable function provider is set', async () => {
+			// eslint-disable-next-line
 			const config = require('~/src/config') as Config;
 			await config.initialized();
 			await expect(config.set({ version: 'some-version' })).to.be.rejected;
 		});
 
 		it('should throw if a non-mutable function provider is removed', async () => {
+			// eslint-disable-next-line
 			const config = require('~/src/config') as Config;
 			await config.initialized();
 			await expect(config.remove('version' as any)).to.be.rejected;
@@ -181,14 +194,15 @@ describe('config', () => {
 	});
 
 	describe('Config data sources', () => {
-		afterEach(() => {
+		afterEach(async () => {
 			// Clean up memoized values
-			fnSchema.deviceArch.clear();
+			await fnSchema.deviceArch.clear();
-			fnSchema.deviceType.clear();
+			await fnSchema.deviceType.clear();
 		});
 
 		it('should obtain deviceArch from device-type.json', async () => {
 			const dtJson = await readDeviceTypeJson();
+			// eslint-disable-next-line
 			const config = require('~/src/config') as Config;
 			await config.initialized();
 
@@ -198,6 +212,7 @@ describe('config', () => {
 
 		it('should obtain deviceType from device-type.json', async () => {
 			const dtJson = await readDeviceTypeJson();
+			// eslint-disable-next-line
 			const config = require('~/src/config') as Config;
 			await config.initialized();
 
@@ -206,6 +221,7 @@ describe('config', () => {
 		});
 
 		it('should memoize values from device-type.json', async () => {
+			// eslint-disable-next-line
 			const config = require('~/src/config') as Config;
 			await config.initialized();
 			const dtJson = await readDeviceTypeJson();
@@ -233,6 +249,7 @@ describe('config', () => {
 		});
 
 		it('should not memoize errors when reading deviceArch', async () => {
+			// eslint-disable-next-line
 			const config = require('~/src/config') as Config;
 			await config.initialized();
 
@@ -253,6 +270,7 @@ describe('config', () => {
 		});
 
 		it('should not memoize errors when reading deviceType', async () => {
+			// eslint-disable-next-line
 			const config = require('~/src/config') as Config;
 			await config.initialized();
 

test/integration/config/splash-image.spec.ts

@@ -1,5 +1,6 @@
 import { promises as fs } from 'fs';
-import { testfs, TestFs } from 'mocha-pod';
+import type { TestFs } from 'mocha-pod';
+import { testfs } from 'mocha-pod';
 
 import { expect } from 'chai';
 import * as hostUtils from '~/lib/host-utils';

test/integration/config/utils.spec.ts

@@ -7,7 +7,7 @@ import { Extlinux } from '~/src/config/backends/extlinux';
 import { ConfigTxt } from '~/src/config/backends/config-txt';
 import { ConfigFs } from '~/src/config/backends/config-fs';
 import { SplashImage } from '~/src/config/backends/splash-image';
-import { ConfigBackend } from '~/src/config/backends/backend';
+import type { ConfigBackend } from '~/src/config/backends/backend';
 
 import * as hostUtils from '~/lib/host-utils';
 

test/integration/db.spec.ts

@@ -1,4 +1,5 @@
-import { knex, Knex } from 'knex';
+import type { Knex } from 'knex';
+import { knex } from 'knex';
 import { promises as fs } from 'fs';
 
 import { expect } from 'chai';
@@ -56,6 +57,7 @@ describe('db', () => {
 	});
 
 	it('creates a database at the path passed on creation', async () => {
+		// eslint-disable-next-line
 		const testDb = require('~/src/db') as Db;
 		await testDb.initialized();
 		await expect(fs.access(constants.databasePath)).to.not.be.rejected;
@@ -64,6 +66,7 @@ describe('db', () => {
 	it('migrations add new fields and removes old ones in an old database', async () => {
 		// Create a database with an older schema
 		const knexForDB = await createOldDatabase(constants.databasePath);
+		// eslint-disable-next-line
 		const testDb = require('~/src/db') as Db;
 		await testDb.initialized();
 		await Promise.all([
@@ -87,6 +90,7 @@ describe('db', () => {
 	});
 
 	it('creates a deviceConfig table with a single default value', async () => {
+		// eslint-disable-next-line
 		const testDb = require('~/src/db') as Db;
 		await testDb.initialized();
 		const deviceConfig = await testDb.models('deviceConfig').select();
@@ -95,6 +99,7 @@ describe('db', () => {
 	});
 
 	it('allows performing transactions', async () => {
+		// eslint-disable-next-line
 		const testDb = require('~/src/db') as Db;
 		await testDb.initialized();
 		return testDb.transaction((trx) => expect(trx.commit()).to.be.fulfilled);

test/integration/device-api/actions.spec.ts

@@ -1,5 +1,6 @@
 import { expect } from 'chai';
-import { stub, SinonStub } from 'sinon';
+import type { SinonStub } from 'sinon';
+import { stub } from 'sinon';
 import * as Docker from 'dockerode';
 import * as request from 'supertest';
 import { setTimeout } from 'timers/promises';
@@ -191,17 +192,21 @@ describe('manages application lifecycle', () => {
 		// This test suite will timeout if anything goes wrong, since
 		// we don't have any way of knowing whether Docker has finished
 		// setting up containers or not.
-		while (true) {
+		let containers = await docker.listContainers({ all: true });
-			const containers = await docker.listContainers({ all: true });
+		let containerInspects = await Promise.all(
-			const containerInspects = await Promise.all(
 			containers.map(({ Id }) => docker.getContainer(Id).inspect()),
 		);
-			if (expected === containers.length && isWaitComplete(containerInspects)) {
+		while (
-				return containerInspects;
+			expected !== containers.length ||
-			} else {
+			!isWaitComplete(containerInspects)
+		) {
 			await setTimeout(500);
+			containers = await docker.listContainers({ all: true });
+			containerInspects = await Promise.all(
+				containers.map(({ Id }) => docker.getContainer(Id).inspect()),
+			);
 		}
-		}
+		return containerInspects;
 	};
 
 	// Get NEW container inspects. This function should be passed to waitForSetup
@@ -217,12 +222,10 @@ describe('manages application lifecycle', () => {
 		// Images are ignored in local mode so we need to pull the base image
 		await docker.pull(BASE_IMAGE);
 		// Wait for base image to finish pulling
-		while (true) {
+		let images = await docker.listImages();
-			const images = await docker.listImages();
+		while (images.length === 0) {
-			if (images.length > 0) {
-				break;
-			}
 			await setTimeout(500);
+			images = await docker.listImages();
 		}
 	});
 

test/integration/device-api/api-keys.spec.ts

@@ -6,7 +6,7 @@ import * as config from '~/src/config';
 import * as testDb from '~/src/db';
 import * as deviceApi from '~/src/device-api';
 import * as middleware from '~/src/device-api/middleware';
-import { AuthorizedRequest } from '~/src/device-api/api-keys';
+import type { AuthorizedRequest } from '~/src/device-api/api-keys';
 
 describe('device-api/api-keys', () => {
 	let app: express.Application;

test/integration/device-api/index.spec.ts

@@ -1,4 +1,4 @@
-import * as express from 'express';
+import type * as express from 'express';
 import * as request from 'supertest';
 
 import * as deviceApi from '~/src/device-api';
@@ -10,7 +10,7 @@ describe('device-api/index', () => {
 		api = new deviceApi.SupervisorAPI({
 			routers: [],
 			healthchecks: [],
-			// @ts-expect-error
+			// @ts-expect-error extract private variable for testing
 		}).api;
 		// Express app set in SupervisorAPI is private here
 		// but we need to access it for supertest

test/integration/device-api/v1.spec.ts

@@ -1,12 +1,13 @@
 import { expect } from 'chai';
-import * as express from 'express';
+import type * as express from 'express';
-import { SinonStub, stub } from 'sinon';
+import type { SinonStub } from 'sinon';
+import { stub } from 'sinon';
 import * as request from 'supertest';
 
 import * as config from '~/src/config';
 import * as db from '~/src/db';
 import * as hostConfig from '~/src/host-config';
-import Service from '~/src/compose/service';
+import type Service from '~/src/compose/service';
 import * as deviceApi from '~/src/device-api';
 import * as actions from '~/src/device-api/actions';
 import * as v1 from '~/src/device-api/v1';
@@ -32,7 +33,7 @@ describe('device-api/v1', () => {
 		api = new deviceApi.SupervisorAPI({
 			routers: [v1.router],
 			healthchecks: [],
-			// @ts-expect-error
+			// @ts-expect-error extract private variable for testing
 		}).api;
 	});
 
@@ -41,7 +42,7 @@ describe('device-api/v1', () => {
 			api = new deviceApi.SupervisorAPI({
 				routers: [v1.router],
 				healthchecks: [],
-				// @ts-expect-error
+				// @ts-expect-error extract private variable for testing
 			}).api;
 		});
 
@@ -49,7 +50,7 @@ describe('device-api/v1', () => {
 			api = new deviceApi.SupervisorAPI({
 				routers: [v1.router],
 				healthchecks: [stub().resolves(true), stub().resolves(true)],
-				// @ts-expect-error
+				// @ts-expect-error extract private variable for testing
 			}).api;
 			await request(api).get('/v1/healthy').expect(200);
 		});
@@ -58,7 +59,7 @@ describe('device-api/v1', () => {
 			api = new deviceApi.SupervisorAPI({
 				routers: [v1.router],
 				healthchecks: [stub().resolves(false), stub().resolves(true)],
-				// @ts-expect-error
+				// @ts-expect-error extract private variable for testing
 			}).api;
 			await request(api).get('/v1/healthy').expect(500);
 		});

test/integration/device-api/v2.spec.ts

@@ -1,6 +1,7 @@
 import { expect } from 'chai';
-import * as express from 'express';
+import type * as express from 'express';
-import { SinonStub, stub } from 'sinon';
+import type { SinonStub } from 'sinon';
+import { stub } from 'sinon';
 import * as request from 'supertest';
 
 import * as config from '~/src/config';
@@ -28,7 +29,7 @@ describe('device-api/v2', () => {
 		api = new deviceApi.SupervisorAPI({
 			routers: [v2.router],
 			healthchecks: [],
-			// @ts-expect-error
+			// @ts-expect-error extract private variable for testing
 		}).api;
 	});
 

test/integration/device-config.spec.ts

@@ -1,7 +1,8 @@
 import { stripIndent } from 'common-tags';
 import { promises as fs } from 'fs';
 import * as path from 'path';
-import { SinonStub, stub, spy, SinonSpy } from 'sinon';
+import type { SinonStub, SinonSpy } from 'sinon';
+import { stub, spy } from 'sinon';
 import { expect } from 'chai';
 
 import * as deviceConfig from '~/src/device-config';

test/integration/device-state.spec.ts

@@ -6,7 +6,7 @@ import * as updateLock from '~/lib/update-lock';
 import * as config from '~/src/config';
 import * as deviceState from '~/src/device-state';
 import { appsJsonBackup, loadTargetFromFile } from '~/src/device-state/preload';
-import { TargetState } from '~/src/types';
+import type { TargetState } from '~/src/types';
 import { promises as fs } from 'fs';
 import { initializeContractRequirements } from '~/lib/contracts';
 
@@ -196,7 +196,7 @@ describe('device-state', () => {
 
 	it('does not allow setting an invalid target state', () => {
 		// v2 state should be rejected
-		expect(
+		return expect(
 			deviceState.setTarget({
 				local: {
 					name: 'aDeviceWithDifferentName',

test/integration/host-config.spec.ts

@@ -1,13 +1,15 @@
 import { expect } from 'chai';
-import { testfs, TestFs } from 'mocha-pod';
+import type { TestFs } from 'mocha-pod';
+import { testfs } from 'mocha-pod';
 import * as path from 'path';
-import { SinonStub, stub } from 'sinon';
+import type { SinonStub } from 'sinon';
+import { stub } from 'sinon';
 import * as fs from 'fs/promises';
 
 import * as hostConfig from '~/src/host-config';
 import * as config from '~/src/config';
 import * as applicationManager from '~/src/compose/application-manager';
-import { InstancedAppState } from '~/src/types/state';
+import type { InstancedAppState } from '~/src/types/state';
 import * as updateLock from '~/lib/update-lock';
 import { UpdatesLockedError } from '~/lib/errors';
 import * as dbus from '~/lib/dbus';

test/integration/lib/firewall.spec.ts

@@ -10,7 +10,8 @@ import * as dbFormat from '~/src/device-state/db-format';
 import * as iptables from '~/lib/iptables';
 import * as firewall from '~/lib/firewall';
 import * as constants from '~/lib/constants';
-import { RuleAction, Rule } from '~/lib/iptables';
+import type { Rule } from '~/lib/iptables';
+import { RuleAction } from '~/lib/iptables';
 import { log } from '~/lib/supervisor-console';
 
 describe('lib/firewall', function () {

test/integration/lib/lockfile.spec.ts

@@ -1,6 +1,7 @@
 import { expect } from 'chai';
 import { promises as fs, mkdirSync } from 'fs';
-import { testfs, TestFs } from 'mocha-pod';
+import type { TestFs } from 'mocha-pod';
+import { testfs } from 'mocha-pod';
 import * as os from 'os';
 import * as path from 'path';
 import { stub } from 'sinon';
@@ -174,7 +175,7 @@ describe('lib/lockfile', () => {
 		await expect(lockfile.lock(lockOne)).to.not.be.rejected;
 		await expect(lockfile.lock(lockTwo, NOBODY_UID)).to.not.be.rejected;
 
-		// @ts-expect-error
+		// @ts-expect-error simulate process exit event
 		process.emit('exit');
 
 		// Verify lockfile removal regardless of appId / appUuid