Fix Plex data transformation, handle socket errors

src/util/Socket.ts

@@ -5,13 +5,14 @@ import {Deferred, defer} from "./Deferred"
 export class Socket {
   ws?: WebSocket
   url: string
-  ready?: Deferred<void>
+  ready: Deferred<void>
   timeout?: NodeJS.Timeout
   queue: string[]
   bus: EventBus
   status: string
   _onOpen: (e: any) => void
   _onMessage: (e: any) => void
+  _onError: (e: any) => void
   _onClose: (e: any) => void
   static STATUS = {
     NEW: "new",
@@ -22,29 +23,33 @@ export class Socket {
   constructor(url: string) {
     this.ws = undefined
     this.url = url
-    this.ready = undefined
+    this.ready = defer()
     this.timeout = undefined
     this.queue = []
     this.bus = new EventBus()
     this.status = Socket.STATUS.NEW
 
-    this._onOpen = e => {
+    this._onOpen = () => {
       this.status = Socket.STATUS.READY
-      this.ready?.resolve()
+      this.ready.resolve()
       this.bus.emit('open')
     }
 
-    this._onMessage = e => {
-      this.queue.push(e.data as string)
+    this._onMessage = event => {
+      this.queue.push(event.data as string)
 
       if (!this.timeout) {
         this.handleMessagesAsync()
       }
     }
 
-    this._onClose = e => {
+    this._onError = (err: Error) => {
+      this.bus.emit('error', err)
+    }
+
+    this._onClose = () => {
       this.disconnect()
-      this.ready?.reject()
+      this.ready.reject()
       this.status = Socket.STATUS.CLOSED
       this.bus.emit('close')
     }
@@ -61,17 +66,25 @@ export class Socket {
 
       this.ws.addEventListener("open", this._onOpen)
       this.ws.addEventListener("message", this._onMessage)
+      this.ws.addEventListener("error", this._onError)
       this.ws.addEventListener("close", this._onClose)
     }
 
-    await this.ready?.catch(() => null)
+    await this.ready.catch(() => null)
   }
   disconnect() {
-    this.ws?.close()
-    this.ws?.removeEventListener("open", this._onOpen)
-    this.ws?.removeEventListener("message", this._onMessage)
-    this.ws?.removeEventListener("close", this._onClose)
-    this.ws = undefined
+    if (this.ws) {
+      const ws = this.ws
+
+      // Avoid "WebSocket was closed before the connection was established"
+      this.ready.then(() => ws.close())
+
+      this.ws.removeEventListener("open", this._onOpen)
+      this.ws.removeEventListener("message", this._onMessage)
+      this.ws.removeEventListener("error", this._onError)
+      this.ws.removeEventListener("close", this._onClose)
+      this.ws = undefined
+    }
   }
   cleanup() {
     this.disconnect()