Store payloads in a queue when arriving in parallel

When messages arrive very quickly after each other, or the message handler is waiting for the Blob arraybuffer to resolve (it's async), it can happen that another message that arrived in parallel resolves the promise already, loosing the first message.

This commit introduces a payload queue, in which payloads that take longer are stored, and taken out on the next iteration.

Attention: The queue is only processed when a new message arrives.

Author: sisou

client/ws.ts

@@ -13,6 +13,7 @@ function isObject(obj: unknown): obj is Record<string, unknown> {
 export class Remote {
   private textDecoder?: TextDecoder;
   private payloadData!: Promise<JsonValue>;
+  private payloadQueue: JsonValue[] = [];
   socket: WebSocket;
   [key: string]: any // necessary for es6 proxy
   constructor(
@@ -24,6 +25,13 @@ export class Remote {
 
   private async getPayloadData(socket: WebSocket): Promise<void> {
     this.payloadData = new Promise<JsonValue>((resolve, reject) => {
+      if (this.payloadQueue.length > 0) {
+        const payload = this.payloadQueue.shift()!;
+        resolve(payload);
+        return;
+      }
+
+      let isResolved = false;
       socket.onmessage = async (event: MessageEvent) => {
         let msg: string;
         if (event.data instanceof Blob) {
@@ -34,7 +42,13 @@ export class Remote {
           msg = event.data;
         }
         try {
-          resolve(JSON.parse(msg));
+          const payload = JSON.parse(msg);
+          if (isResolved) {
+            this.payloadQueue.push(payload);
+            return;
+          }
+          resolve(payload);
+          isResolved = true;
         } catch (err) {
           reject(
             new BadServerDataError(null, "The received data is invalid JSON."),