Send and receive message

packages/status-communities/package.json

@@ -23,6 +23,7 @@
     "proto:build": "buf generate"
   },
   "devDependencies": {
+    "@types/chai": "^4.2.22",
     "@types/mocha": "^9.0.0",
     "@typescript-eslint/eslint-plugin": "^4.31.1",
     "@typescript-eslint/parser": "^4.31.1",

packages/status-communities/src/chat.ts

@@ -14,19 +14,21 @@ export class Chat {
     return chatIdToContentTopic(this.id);
   }
 
-  private createMessage(text: string): ChatMessage {
-    const { timestamp, clock } = this.nextClockAndTimestamp();
+  public createMessage(text: string): ChatMessage {
+    const { timestamp, clock } = this._nextClockAndTimestamp();
 
-    return ChatMessage.createMessage(clock, timestamp, text, this.id);
+    const message = ChatMessage.createMessage(clock, timestamp, text, this.id);
+
+    this._updateFromMessage(message);
+
+    return message;
   }
 
   public handleNewMessage(message: ChatMessage) {
-    this.updateFromMessage(message);
-
-    // TODO: emit message
+    this._updateFromMessage(message);
   }
 
-  private nextClockAndTimestamp(): { clock: number; timestamp: number } {
+  private _nextClockAndTimestamp(): { clock: number; timestamp: number } {
     let clock = this.lastClockValue;
     const timestamp = Date.now();
 
@@ -39,7 +41,7 @@ export class Chat {
     return { clock, timestamp };
   }
 
-  private updateFromMessage(message: ChatMessage): void {
+  private _updateFromMessage(message: ChatMessage): void {
     if (!this.lastMessage || this.lastMessage.clock <= message.clock) {
       this.lastMessage = message;
     }

packages/status-communities/src/chat_message.ts

@@ -46,7 +46,15 @@ export class ChatMessage {
     return new ChatMessage(protoBuf);
   }
 
+  encode(): Uint8Array {
+    return proto.ChatMessage.encode(this.proto).finish();
+  }
+
   public get clock() {
     return this.proto.clock;
   }
+
+  get text(): string | undefined {
+    return this.proto.text;
+  }
 }

packages/status-communities/src/messenger.spec.ts

@@ -1,7 +1,6 @@
-// eslint-disable-next-line @typescript-eslint/ban-ts-comment
-// @ts-ignore: No types available
-import TCP from "libp2p-tcp";
+import { expect } from "chai";
 
+import { ChatMessage } from "./chat_message";
 import { Messenger } from "./messenger";
 
 const testChatId = "test-chat-id";
@@ -38,9 +37,25 @@ describe("Messenger", () => {
     ]);
   });
 
-  it("Sends message in public chat", function () {
+  it("Sends & Receive message in public chat", async function () {
     messenger1.joinChat(testChatId);
     messenger2.joinChat(testChatId);
+
+    const text = "This is a message.";
+
+    const receivedMessagePromise: Promise<ChatMessage> = new Promise(
+      (resolve) => {
+        messenger2.addObserver((message) => {
+          resolve(message);
+        }, testChatId);
+      }
+    );
+
+    messenger1.sendMessage(text, testChatId);
+
+    const receivedMessage = await receivedMessagePromise;
+
+    expect(receivedMessage?.text).to.eq(text);
   });
 
   afterEach(async function () {

packages/status-communities/src/messenger.ts

@@ -6,21 +6,28 @@ import { ChatMessage } from "./chat_message";
 
 export class Messenger {
   waku: Waku;
-
   chatsById: Map<string, Chat>;
+  observers: {
+    [chatId: string]: Set<(chatMessage: ChatMessage) => void>;
+  };
 
   private constructor(waku: Waku) {
     this.waku = waku;
     this.chatsById = new Map();
+    this.observers = {};
   }
 
   public static async create(wakuOptions?: WakuCreateOptions) {
     const _wakuOptions = Object.assign({ bootstrap: true }, wakuOptions);
     const waku = await Waku.create(_wakuOptions);
-    const messenger = new Messenger(waku);
-    return messenger;
+    return new Messenger(waku);
   }
 
+  /**
+   * Joins a public chat.
+   *
+   * Use `addListener` to get messages received on this chat.
+   */
   public joinChat(chatId: string) {
     if (this.chatsById.has(chatId)) throw "Chat already joined";
 
@@ -33,6 +40,12 @@ export class Messenger {
         const chatMessage = ChatMessage.decode(wakuMessage.payload);
 
         chat.handleNewMessage(chatMessage);
+
+        if (this.observers[chatId]) {
+          this.observers[chatId].forEach((observer) => {
+            observer(chatMessage);
+          });
+        }
       },
       [chat.contentTopic]
     );
@@ -40,6 +53,64 @@ export class Messenger {
     this.chatsById.set(chatId, chat);
   }
 
+  /**
+   * Sends a message on the given chat Id.
+   *
+   * @param text
+   * @param chatId
+   */
+  public async sendMessage(text: string, chatId: string): Promise<void> {
+    const chat = this.chatsById.get(chatId);
+    if (!chat) throw `Chat not joined: ${chatId}`;
+
+    const message = chat.createMessage(text);
+
+    const wakuMessage = await WakuMessage.fromBytes(
+      message.encode(),
+      chat.contentTopic
+    );
+
+    await this.waku.relay.send(wakuMessage);
+  }
+
+  /**
+   * Add an observer of new messages received on the chat.
+   *
+   * @throws string If the chat has not been joined first using [joinChat].
+   */
+  public addObserver(
+    observer: (chatMessage: ChatMessage) => void,
+    chatId: string
+  ) {
+    // Not sure this is the best design here. Maybe `addObserver` and `joinChat` should be merged.
+
+    if (!this.chatsById.has(chatId))
+      throw "Cannot add observer on a chat that is not joined.";
+    if (!this.observers[chatId]) {
+      this.observers[chatId] = new Set();
+    }
+
+    this.observers[chatId].add(observer);
+  }
+
+  /**
+   * Add an observer of new messages received on the chat.
+   *
+   * @throws string If the chat has not been joined first using [joinChat].
+   */
+
+  deleteObserver(
+    observer: (chatMessage: ChatMessage) => void,
+    chatId: string
+  ): void {
+    if (this.observers[chatId]) {
+      this.observers[chatId].delete(observer);
+    }
+  }
+
+  /**
+   * Stops the messenger.
+   */
   public async stop(): Promise<void> {
     await this.waku.stop();
   }

packages/status-communities/tsconfig.json

@@ -38,7 +38,11 @@
     "skipLibCheck": true,
 
     "lib": ["es6", "dom"],
-    "typeRoots": ["./node_modules/@types", "./src/types", "../../node_modules/@types"]
+    "typeRoots": [
+      "./node_modules/@types",
+      "./src/types",
+      "../../node_modules/@types"
+    ]
   },
   "include": ["src"],
   "exclude": ["node_modules/**"],

yarn.lock

@@ -448,6 +448,13 @@ __metadata:
   languageName: node
   linkType: hard
 
+"@types/chai@npm:^4.2.22":
+  version: 4.2.22
+  resolution: "@types/chai@npm:4.2.22"
+  checksum: dca66a263b25c26112c0a8c6df20316412fa54b557443a108836c07cee961aa56cc5b1763273f69eb450c83ca9f28069ff78b617bffc01806cdd83afc1c20c2a
+  languageName: node
+  linkType: hard
+
 "@types/debug@npm:^4.1.5":
   version: 4.1.7
   resolution: "@types/debug@npm:4.1.7"
@@ -5531,6 +5538,7 @@ fsevents@~2.3.2:
   version: 0.0.0-use.local
   resolution: "status-communities@workspace:packages/status-communities"
   dependencies:
+    "@types/chai": ^4.2.22
     "@types/mocha": ^9.0.0
     "@typescript-eslint/eslint-plugin": ^4.31.1
     "@typescript-eslint/parser": ^4.31.1