Add Realm support to Relay (#226)

* add(): realm relay

* fix(): Non-async solution to realm proxy

* fix(): follow the guidlines of the strict linter

* fix(): Use Client constructor instead of createClient function

* types(): Update index.d.ts to include realms option in destination

examples/realmRelay.js

@@ -0,0 +1,29 @@
+const { Relay } = require('bedrock-protocol')
+
+function createRelay () {
+  console.log('Creating relay')
+  /* Example to create a non-transparent proxy (or 'Relay') connection to destination server */
+  const relay = new Relay({
+    /* host and port for clients to listen to */
+    host: '0.0.0.0',
+    port: 19130,
+    offline: false,
+    /* Where to send upstream packets to */
+    destination: {
+      realms: {
+        pickRealm: (realms) => realms.find(e => e.name === 'Realm Name')
+      },
+      offline: false
+    }
+  })
+  relay.conLog = console.debug
+  relay.listen()
+  relay.on('connect', player => {
+    // Server is sending a message to the client.
+    player.on('clientbound', ({ name, params }) => {
+      if (name === 'text') console.log(params)
+    })
+  })
+}
+
+createRelay()

index.d.ts

@@ -153,6 +153,7 @@ declare module "bedrock-protocol" {
     authTitle: title | string
     // Where to proxy requests to.
     destination: {
+      realms?: RealmsOptions
       host: string,
       port: number,
       // Skip authentication connecting to the remote server?

src/relay.js

@@ -1,6 +1,7 @@
 const { Client } = require('./client')
 const { Server } = require('./server')
 const { Player } = require('./serverPlayer')
+const { realmAuthenticate } = require('./client/auth')
 const debug = globalThis.isElectron ? console.debug : require('debug')('minecraft-protocol')
 
 const debugging = false // Do re-encoding tests
@@ -170,18 +171,25 @@ class Relay extends Server {
   // a packet, no matter what state it's in. For example, if the client wants to send a
   // packet to the server but it's not connected, it will add to the queue and send as soon
   // as a connection with the server is established.
-  openUpstreamConnection (ds, clientAddr) {
-    const client = new Client({
+  async openUpstreamConnection (ds, clientAddr) {
+    const options = {
       authTitle: this.options.authTitle,
       offline: this.options.destination.offline ?? this.options.offline,
       username: this.options.offline ? ds.profile.name : null,
       version: this.options.version,
+      realms: this.options.destination.realms,
       host: this.options.destination.host,
       port: this.options.destination.port,
       onMsaCode: this.options.onMsaCode,
       profilesFolder: this.options.profilesFolder,
       autoInitPlayer: false
-    })
+    }
+
+    if (this.options.destination.realms) {
+      await realmAuthenticate(options)
+    }
+
+    const client = new Client(options)
     // Set the login payload unless `noLoginForward` option
     if (!client.noLoginForward) client.options.skinData = ds.skinData
     client.ping().then(pongData => {
@@ -189,7 +197,7 @@ class Relay extends Server {
     }).catch(err => {
       this.emit('error', err)
     })
-    this.conLog('Connecting to', this.options.destination.host, this.options.destination.port)
+    this.conLog('Connecting to', options.host, options.port)
     client.outLog = ds.upOutLog
     client.inLog = ds.upInLog
     client.once('join', () => {