fix(dns-discovery): Use DOH list from dns-query

To make the library more robust as not all DOH allow CORS. Previous
default DOH got CORS disabled.

Author: fryorcraken

package-lock.json

@@ -4,9 +4,9 @@ const webpack = require("webpack");
 module.exports = function (config) {
   config.set({
     frameworks: ["webpack", "mocha"],
-    files: ["src/**/*.ts"],
+    files: ["src/**/!(node).spec.ts"],
     preprocessors: {
-      "src/**/*.ts": ["webpack"],
+      "src/**/!(node).spec.ts": ["webpack"],
     },
     envPreprocessor: ["CI"],
     reporters: ["progress"],
@@ -20,7 +20,19 @@ module.exports = function (config) {
     webpack: {
       mode: "development",
       module: {
-        rules: [{ test: /\.([cm]?ts|tsx)$/, loader: "ts-loader" }],
+        rules: [
+          {
+            test: /\.([cm]?ts|tsx)$/,
+            use: [
+              {
+                loader: "ts-loader",
+                options: {
+                  configFile: "tsconfig.karma.json",
+                },
+              },
+            ],
+          },
+        ],
       },
       plugins: [
         new webpack.DefinePlugin({

packages/dns-discovery/karma.conf.cjs

@@ -53,7 +53,8 @@
     "prepublish": "npm run build",
     "reset-hard": "git clean -dfx -e .idea && git reset --hard && npm i && npm run build",
     "test": "run-s test:*",
-    "test:node": "TS_NODE_PROJECT=./tsconfig.dev.json mocha"
+    "test:node": "TS_NODE_PROJECT=./tsconfig.dev.json mocha",
+    "test:browser": "karma start karma.conf.cjs"
   },
   "engines": {
     "node": ">=16"
@@ -90,6 +91,10 @@
     "eslint-plugin-functional": "^5.0.4",
     "eslint-plugin-import": "^2.27.5",
     "eslint-plugin-prettier": "^4.2.1",
+    "karma": "^6.4.1",
+    "karma-chrome-launcher": "^3.1.1",
+    "karma-mocha": "^2.0.1",
+    "karma-webpack": "^5.0.0",
     "mocha": "^10.2.0",
     "npm-run-all": "^4.1.5",
     "prettier": "^2.8.4",

packages/dns-discovery/package.json

@@ -273,7 +273,7 @@ describe("DNS Node Discovery [live data]", function () {
   it(`should retrieve ${maxQuantity} multiaddrs for test.waku.nodes.status.im`, async function () {
     this.timeout(10000);
     // Google's dns server address. Needs to be set explicitly to run in CI
-    const dnsNodeDiscovery = DnsNodeDiscovery.dnsOverHttp();
+    const dnsNodeDiscovery = await DnsNodeDiscovery.dnsOverHttp();
     const peers = await dnsNodeDiscovery.getPeers([enrTree.TEST], {
       relay: maxQuantity,
       store: maxQuantity,
@@ -296,7 +296,7 @@ describe("DNS Node Discovery [live data]", function () {
   it(`should retrieve ${maxQuantity} multiaddrs for prod.waku.nodes.status.im`, async function () {
     this.timeout(10000);
     // Google's dns server address. Needs to be set explicitly to run in CI
-    const dnsNodeDiscovery = DnsNodeDiscovery.dnsOverHttp();
+    const dnsNodeDiscovery = await DnsNodeDiscovery.dnsOverHttp();
     const peers = await dnsNodeDiscovery.getPeers([enrTree.PROD], {
       relay: maxQuantity,
       store: maxQuantity,

packages/dns-discovery/src/dns.spec.ts

@@ -33,9 +33,11 @@ export class DnsNodeDiscovery {
   private readonly _DNSTreeCache: { [key: string]: string };
   private readonly _errorTolerance: number = 10;
 
-  public static dnsOverHttp(dnsClient?: DnsClient): DnsNodeDiscovery {
+  public static async dnsOverHttp(
+    dnsClient?: DnsClient
+  ): Promise<DnsNodeDiscovery> {
     if (!dnsClient) {
-      dnsClient = new DnsOverHttps();
+      dnsClient = await DnsOverHttps.create();
     }
     return new DnsNodeDiscovery(dnsClient);
   }

packages/dns-discovery/src/dns.ts

@@ -1,45 +1,32 @@
 import { bytesToUtf8 } from "@waku/utils/bytes";
 import debug from "debug";
-import { Endpoint, query, toEndpoint } from "dns-query";
+import { Endpoint, query, wellknown } from "dns-query";
 
 import { DnsClient } from "./dns.js";
 
 const log = debug("waku:dns-over-https");
 
 export class DnsOverHttps implements DnsClient {
-  /**
-   * Default endpoints to use for DNS queries.
-   * Taken from https://github.com/martinheidegger/dns-query as static data
-   * to avoid dynamic queries.
-   *
-   * To dynamically retrieve other endpoints, use https://github.com/martinheidegger/dns-query#well-known-endpoints
-   */
-  static DefaultEndpoints: Endpoint[] = [
-    toEndpoint({
-      name: "AhaDNS",
-      protocol: "https:",
-      host: "doh.la.ahadns.net",
-      ipv4: "45.67.219.208",
-    }),
-    toEndpoint({
-      name: "cloudflare",
-      protocol: "https:",
-      host: "dns.cloudflare.com",
-      ipv4: "1.0.0.1",
-    }),
-  ];
-
   /**
    * Create new Dns-Over-Http DNS client.
    *
    * @param endpoints The endpoints for Dns-Over-Https queries;
-   * Defaults to [[DnsOverHttps.DefaultEndpoints]].
+   * Defaults to using dns-query's API..
    * @param retries Retries if a given endpoint fails.
    *
    * @throws {code: string} If DNS query fails.
    */
-  public constructor(
-    private endpoints: Endpoint[] = DnsOverHttps.DefaultEndpoints,
+  public static async create(
+    endpoints?: Endpoint[],
+    retries?: number
+  ): Promise<DnsOverHttps> {
+    const _endpoints = endpoints ?? (await wellknown.endpoints("doh"));
+
+    return new DnsOverHttps(_endpoints, retries);
+  }
+
+  private constructor(
+    private endpoints: Endpoint[],
     private retries: number = 3
   ) {}
 

packages/dns-discovery/src/dns_over_https.ts

@@ -60,7 +60,7 @@ export class PeerDiscoveryDns
   extends EventEmitter<PeerDiscoveryEvents>
   implements PeerDiscovery
 {
-  private readonly nextPeer: () => AsyncGenerator<IEnr>;
+  private nextPeer: (() => AsyncGenerator<IEnr>) | undefined;
   private _started: boolean;
   private _components: DnsDiscoveryComponents;
   private _options: Options;
@@ -71,17 +71,8 @@ export class PeerDiscoveryDns
     this._components = components;
     this._options = options;
 
-    const { enrUrl, wantedNodeCapabilityCount } = options;
-
+    const { enrUrl } = options;
     log("Use following EIP-1459 ENR Tree URL: ", enrUrl);
-
-    const dns = DnsNodeDiscovery.dnsOverHttp();
-
-    this.nextPeer = dns.getNextPeer.bind(
-      dns,
-      [enrUrl],
-      wantedNodeCapabilityCount
-    );
   }
 
   /**
@@ -91,6 +82,18 @@ export class PeerDiscoveryDns
     log("Starting peer discovery via dns");
 
     this._started = true;
+
+    if (this.nextPeer === undefined) {
+      const { enrUrl, wantedNodeCapabilityCount } = this._options;
+      const dns = await DnsNodeDiscovery.dnsOverHttp();
+
+      this.nextPeer = dns.getNextPeer.bind(
+        dns,
+        [enrUrl],
+        wantedNodeCapabilityCount
+      );
+    }
+
     for await (const peer of this.nextPeer()) {
       if (!this._started) return;
 

packages/dns-discovery/src/index.ts

@@ -0,0 +1,7 @@
+{
+  "extends": "./tsconfig",
+  "compilerOptions": {
+    "module": "esnext"
+  },
+  "exclude": []
+}

packages/dns-discovery/tsconfig.karma.json

@@ -90,7 +90,7 @@ describe("DNS Node Discovery [live data]", function () {
 
     this.timeout(10000);
     // Google's dns server address. Needs to be set explicitly to run in CI
-    const dnsNodeDiscovery = DnsNodeDiscovery.dnsOverHttp();
+    const dnsNodeDiscovery = await DnsNodeDiscovery.dnsOverHttp();
 
     const peers = await dnsNodeDiscovery.getPeers([enrTree["PROD"]], {
       relay: maxQuantity,