Replace runtypes with zod, validate config, stricter eslint config

.eslintrc.js

@@ -1,11 +1,10 @@
 module.exports = {
-    extends: ['eslint:recommended', 'plugin:@typescript-eslint/recommended'],
+    extends: ['eslint:recommended'],
     parser: '@typescript-eslint/parser',
     plugins: ['@typescript-eslint', 'prettier'],
     root: true,
     rules: {
         'prettier/prettier': 'warn',
-        '@typescript-eslint/explicit-module-boundary-types': 'error',
         'prefer-arrow-callback': 'error',
         'sort-imports': [
             'error',
@@ -15,6 +14,19 @@ module.exports = {
         ],
     },
     overrides: [
+        {
+            files: ['**/*.ts'],
+            extends: [
+                'plugin:@typescript-eslint/recommended',
+                'plugin:@typescript-eslint/recommended-requiring-type-checking',
+            ],
+            parserOptions: {
+                project: ['./tsconfig.json'],
+            },
+            rules: {
+                '@typescript-eslint/explicit-module-boundary-types': 'error',
+            },
+        },
         {
             files: ['.eslintrc.js', 'jest.config.js', 'prettier.config.js'],
             env: {

config.schema.json

@@ -4,11 +4,13 @@
     "singular": true,
     "schema": {
         "type": "object",
+        "required": ["pin"],
         "properties": {
             "pin": {
                 "title": "Pin",
                 "description": "Homebridge PIN for service authentication",
                 "type": "string",
+                "pattern": "^\\d{3}-\\d{2}-\\d{3}$",
                 "required": true
             },
             "debug": {

flake.nix

@@ -16,6 +16,6 @@
 
       in with pkgs; rec {
 
-        devShell = pkgs.mkShell rec { buildInputs = with pkgs; [ nodejs ]; };
+        devShell = pkgs.mkShell rec { buildInputs = with pkgs; [ nodejs jq ]; };
       });
 }

package.json

@@ -15,7 +15,7 @@
         "node": ">=14.18.1",
         "homebridge": ">=1.3.5"
     },
-    "main": "dist/index.js",
+    "main": "dist/src/index.js",
     "scripts": {
         "lint": "npm run format && eslint --ignore-path=.gitignore '**/**.{ts,js,json}'",
         "watch": "npm run build && npm run link && nodemon",
@@ -47,6 +47,10 @@
     "dependencies": {
         "fastify": "^4.9.2",
         "hap-node-client": "git+https://github.com/NorthernMan54/Hap-Node-Client.git#fe200ba",
-        "runtypes": "^6.6.0"
+        "json-schema-to-zod": "^0.2.0",
+        "zod": "^3.19.1"
+    },
+    "overrides": {
+        "jest-mock": "29.2"
     }
 }

src/adapters/discovery/api.ts

@@ -1,4 +1,4 @@
-import type { Device } from '../../boundaries'
+import type { Device } from '../../boundaries/hap'
 import { Logger } from 'homebridge'
 
 type Pin = string

src/adapters/discovery/hap_node_js_client.ts

@@ -1,10 +1,10 @@
 import type { HapDiscover } from './api'
 import { HAPNodeJSClient } from 'hap-node-client'
-import { Device, DeviceBoundary } from '../../boundaries'
+import { Device, DeviceBoundary } from '../../boundaries/hap'
-import { Array, Unknown } from 'runtypes'
 import { Logger } from 'homebridge'
+import z from 'zod'
 
-const MaybeDevices = Array(Unknown)
+const MaybeDevices = z.array(z.unknown())
 
 interface HapConfig {
     debug: boolean
@@ -13,11 +13,10 @@ interface HapConfig {
     reqTimeout: number
     pin: string
 }
-type HapClient = typeof HAPNodeJSClient
 type ResolveFunc = (devices: Device[]) => void
 type RejectFunc = (error: unknown) => void
 
-const clientMap: Record<string, HapClient> = {}
+const clientMap: Record<string, HAPNodeJSClient> = {}
 const promiseMap: Record<string, [ResolveFunc, RejectFunc]> = {}
 
 function startDiscovery(logger: Logger, config: HapConfig, resolve: ResolveFunc, reject: RejectFunc) {
@@ -30,9 +29,9 @@ function startDiscovery(logger: Logger, config: HapConfig, resolve: ResolveFunc,
             try {
                 const devices: Device[] = []
 
-                for (const device of MaybeDevices.check(deviceData)) {
+                for (const device of MaybeDevices.parse(deviceData)) {
                     try {
-                        devices.push(DeviceBoundary.check(device))
+                        devices.push(DeviceBoundary.parse(device))
                     } catch (e) {
                         logger.error('Boundary check for device data failed %o %s', e, JSON.stringify(device, null, 4))
                     }

src/ambient.d.ts

@@ -1 +1,15 @@
-declare module 'hap-node-client'
+declare module 'hap-node-client' {
+    type HAPNodeJSClientConfig = {
+        debug?: boolean
+        refresh?: number
+        timeout?: number
+        reqTimeout?: number
+        pin?: string
+    }
+
+    class HAPNodeJSClient {
+        constructor(config: HAPNodeJSClientConfig)
+
+        on(event: 'Ready', callback: (v: unknown) => void): void
+    }
+}

src/boundaries.ts

@@ -1,53 +0,0 @@
-import { Array, Intersect, Literal, Number, Optional, Record, Static, String, Union } from 'runtypes'
-
-export const NUMBER_TYPES = [] as const
-
-const NumberAlikeTypesTypesBoundary = Union(
-    Literal('bool'),
-    Literal('float'),
-    Literal('int'),
-    Literal('uint8'),
-    Literal('uint16'),
-    Literal('uint32'),
-    Literal('uint64'),
-)
-export type NumberAlikeTypes = Static<typeof NumberAlikeTypesTypesBoundary>
-
-export const CharacteristicBoundary = Intersect(
-    Record({ type: String, description: String }),
-    Union(
-        Record({
-            format: NumberAlikeTypesTypesBoundary,
-            value: Optional(Number),
-            unit: Optional(String),
-        }),
-        Record({ format: Literal('string'), value: String }),
-    ),
-)
-export type Characteristic = Static<typeof CharacteristicBoundary>
-
-export const ServiceBoundary = Record({
-    type: String,
-    characteristics: Array(CharacteristicBoundary),
-})
-export type Service = Static<typeof ServiceBoundary>
-
-export const AccessoryBoundary = Record({
-    services: Array(ServiceBoundary),
-})
-export type Accessory = Static<typeof AccessoryBoundary>
-
-export const InstanceBoundary = Record({
-    deviceID: String,
-    name: String,
-    url: String,
-})
-export type Instance = Static<typeof InstanceBoundary>
-
-export const DeviceBoundary = Record({
-    instance: InstanceBoundary,
-    accessories: Record({
-        accessories: Array(AccessoryBoundary),
-    }),
-})
-export type Device = Static<typeof DeviceBoundary>

src/boundaries/config.ts

@@ -0,0 +1,19 @@
+import { z } from 'zod'
+
+export const ConfigBoundary = z.object({
+    pin: z.string().regex(new RegExp('^\\d{3}-\\d{2}-\\d{3}$')).describe('Homebridge PIN for service authentication'),
+    debug: z.boolean().default(false),
+    prefix: z.string().default('homebridge'),
+    port: z.number().int().describe('TCP port for the prometheus probe server to listen to').default(36123),
+    refresh_interval: z.number().int().describe('Discover new services every <interval> seconds').default(60),
+    request_timeout: z
+        .number()
+        .int()
+        .describe('Request timeout when interacting with homebridge instances')
+        .default(10),
+    discovery_timeout: z
+        .number()
+        .int()
+        .describe('Discovery timeout after which the current discovery is considered failed')
+        .default(20),
+})

src/boundaries/hap.ts

@@ -0,0 +1,51 @@
+import z from 'zod'
+
+const NumberAlikeTypesTypesBoundary = z.union([
+    z.literal('bool'),
+    z.literal('float'),
+    z.literal('int'),
+    z.literal('uint8'),
+    z.literal('uint16'),
+    z.literal('uint32'),
+    z.literal('uint64'),
+])
+export type NumberAlikeTypes = z.infer<typeof NumberAlikeTypesTypesBoundary>
+
+export const CharacteristicBoundary = z.intersection(
+    z.object({ type: z.string(), description: z.string() }),
+    z.union([
+        z.object({
+            format: NumberAlikeTypesTypesBoundary,
+            value: z.optional(z.number()),
+            unit: z.optional(z.string()),
+        }),
+        z.object({ format: z.literal('string'), value: z.string() }),
+    ]),
+)
+export type Characteristic = z.infer<typeof CharacteristicBoundary>
+
+export const ServiceBoundary = z.object({
+    type: z.string(),
+    characteristics: z.array(CharacteristicBoundary),
+})
+export type Service = z.infer<typeof ServiceBoundary>
+
+export const AccessoryBoundary = z.object({
+    services: z.array(ServiceBoundary),
+})
+export type Accessory = z.infer<typeof AccessoryBoundary>
+
+export const InstanceBoundary = z.object({
+    deviceID: z.string(),
+    name: z.string(),
+    url: z.string(),
+})
+export type Instance = z.infer<typeof InstanceBoundary>
+
+export const DeviceBoundary = z.object({
+    instance: InstanceBoundary,
+    accessories: z.object({
+        accessories: z.array(AccessoryBoundary),
+    }),
+})
+export type Device = z.infer<typeof DeviceBoundary>

src/boundaries/index.ts

@@ -0,0 +1,6 @@
+import z from 'zod'
+import { ConfigBoundary as BaseConfigBoundary } from './config'
+
+export * from './hap'
+export const ConfigBoundary = z.intersection(BaseConfigBoundary, z.object({ platform: z.string() }))
+export type Config = z.infer<typeof ConfigBoundary>

src/metrics.ts

@@ -1,4 +1,4 @@
-import type { Accessory, Device, Service } from './boundaries'
+import type { Accessory, Device, Service } from './boundaries/hap'
 import { assertTypeExhausted, isType } from './std'
 import { Service as HapService } from 'hap-nodejs'
 

src/platform.ts

@@ -5,18 +5,22 @@ import { discover } from './adapters/discovery/hap_node_js_client'
 import { serve } from './adapters/http/fastify'
 import { HttpServerController } from './adapters/http/api'
 import { PrometheusServer } from './prometheus'
+import { Config, ConfigBoundary } from './boundaries'
 
 export class PrometheusExporterPlatform implements IndependentPlatformPlugin {
     private readonly httpServer: PrometheusServer
     private httpServerController: HttpServerController | undefined = undefined
+    private readonly config: Config
 
-    constructor(public readonly log: Logger, public readonly config: PlatformConfig, public readonly api: API) {
+    constructor(public readonly log: Logger, config: PlatformConfig, public readonly api: API) {
-        this.log.debug('Initializing platform %s', this.config.platform)
+        this.log.debug('Initializing platform %s', config.platform)
 
-        this.configure()
+        this.config = ConfigBoundary.parse(config)
+
+        this.log.debug('Configuration parsed', this.config)
 
         this.api.on('shutdown', () => {
-            this.log.debug('Shutting down %s', this.config.platform)
+            this.log.debug('Shutting down %s', config.platform)
             if (this.httpServerController) {
                 this.httpServerController.shutdown()
             }
@@ -40,21 +44,6 @@ export class PrometheusExporterPlatform implements IndependentPlatformPlugin {
         })
     }
 
-    private configure(): void {
-        if (this.config.pin !== 'string' || !this.config.pin.match(/^\d{3}-\d{2}-\d{3}$/)) {
-            this.log.error('"pin" must be defined in config and match format 000-00-000')
-        }
-
-        this.config.debug = this.config.debug ?? false
-        this.config.port = this.config.port ?? 36123
-        this.config.prefix = this.config.prefix ?? 'homebridge'
-        this.config.refresh_interval = this.config.refresh_interval || 60
-        this.config.request_timeout = this.config.request_timeout || 10
-        this.config.discovery_timeout = this.config.discovery_timeout || 20
-
-        this.log.debug('Configuration materialized: %o', this.config)
-    }
-
     private startHapDiscovery(): void {
         this.log.debug('Starting HAP discovery')
         discover({

tests/aggregator.test.ts

@@ -1,5 +1,5 @@
 import { describe, expect, test } from '@jest/globals'
-import { DeviceBoundary } from '../src/boundaries'
+import { DeviceBoundary } from '../src/boundaries/hap'
 import { Metric, aggregate } from '../src/metrics'
 import dysonData from './fixtures/dyson.json'
 import emptyData from './fixtures/empty.json'
@@ -10,7 +10,7 @@ describe('Metrics aggregator', () => {
     const timestamp = new Date('2000-01-01 00:00:00 UTC')
 
     test('Aggregates homebridge-dyson fan metrics', () => {
-        const dyson = DeviceBoundary.check(dysonData)
+        const dyson = DeviceBoundary.parse(dysonData)
 
         const expectedLabels = {
             bridge: 'Dyson bridge',
@@ -38,13 +38,13 @@ describe('Metrics aggregator', () => {
     })
 
     test('Aggregates empty accessory metrics to empty metrics', () => {
-        const empty = DeviceBoundary.check(emptyData)
+        const empty = DeviceBoundary.parse(emptyData)
 
         expect(aggregate([empty], timestamp)).toEqual([])
     })
 
     test('Aggregates TP-Link plugs metrics', () => {
-        const tpLink = DeviceBoundary.check(tpLinkData)
+        const tpLink = DeviceBoundary.parse(tpLinkData)
 
         const expectedLabelsAccessory1 = {
             bridge: 'TP-Link bridge',
@@ -88,7 +88,7 @@ describe('Metrics aggregator', () => {
     })
 
     test('Aggregates homebridge-harmony remote metrics', () => {
-        const harmony = DeviceBoundary.check(harmonyData)
+        const harmony = DeviceBoundary.parse(harmonyData)
 
         const expectedLabels1 = {
             bridge: 'Harmony bridge',

tsconfig.json

@@ -7,12 +7,12 @@
         "declarationMap": true,
         "sourceMap": true,
         "outDir": "./dist",
-        "rootDir": "./src",
+        "rootDir": "./",
         "strict": true,
         "esModuleInterop": true,
         "noImplicitAny": true,
         "resolveJsonModule": true
     },
-    "include": ["src/"],
+    "include": ["src/", "tests/"],
     "exclude": []
 }