Voice-only quickstart

This Electron quickstart shows you how to create a basic Voice Calling app using the Agora RTC SDK.

Understand the tech

To start a Voice Calling session, implement the following steps in your app:

• Initialize the Agora Engine: Before calling other APIs, create and initialize an Agora Engine instance.

• Join a channel: Call methods to create and join a channel.

• Send and receive audio: All users can publish streams to the channel and subscribe to audio streams published by other users in the channel.

Prerequisites

• Node.js 14 or higher.

• A microphone

• A valid Agora account and project. Please refer to Agora account management for details.

Set up your project

This section shows you how to set up your Electron project and install the Agora RTC SDK.

1. Create a new directory for your Electron project in a local folder. Add the following files to the root of the project directory:

   • package.json: Manages project dependencies and scripts.
   • index.html: Defines the app's user interface.
   • main.js: The main process entry point.
   • renderer.js: The renderer process script, responsible for interacting with the Agora Electron SDK.

2. Create a user interface for your app based on your use-case.

   Refer to Create a user interface to get a bare bones sample layout.

Install the SDK

Manual Integration Compile the latest SDK from the Electron SDK repository and integrate it into your application.

Implement Voice Calling

This section guides you through the implementation of basic real-time audio interaction in your app.

The following figure illustrates the essential steps:

This guide includes complete sample code that demonstrates implementing basic real-time interaction. To understand the core API calls in the sample code, review the following implementation steps.

Set up the main process

The main.js file is the entry point for your Electron application. It defines the main process, which is responsible for creating and managing browser windows. This script initializes the app, loads the UI from index.html, and ensures proper behavior across platforms.

const { app, BrowserWindow } = require("electron");
const path = require("path");

// If using Electron 9.x or later, set allowRendererProcessReuse to false
app.allowRendererProcessReuse = false;

function createWindow() {
  // Create the browser window
  const mainWindow = new BrowserWindow({
    width: 800,
    height: 600,
    webPreferences: {
      // preload: path.join(__dirname, "renderer.js"),
      // Enable Node integration and disable context isolation
      nodeIntegration: true,
      contextIsolation: false,
    },
  });

  // Load the contents of the index.html file
  mainWindow.loadFile("./index.html");
  // Open the Developer Tools
  mainWindow.webContents.openDevTools();
}

// Manage the browser window for the Electron app
app.whenReady().then(() => {
  createWindow();
  // On macOS, create a new window if none are open
  app.on("activate", function () {
    if (BrowserWindow.getAllWindows().length === 0) {
      createWindow();
    }
  });
});

// Quit the Electron app when all windows are closed (except on macOS)
app.on("window-all-closed", function () {
  if (process.platform !== "darwin") app.quit();
});

Handle permissions

Perform this step only when the target platform is macOS. Starting with macOS v10.14, you must check and obtain permission before accessing the microphone. Use Electron’s askForMediaAccess method to request the permission from the user.

Add the following code to the main.js file:

// Check and request microphone permission
async function checkAndApplyDeviceAccessPrivilege() {
  const micPrivilege = systemPreferences.getMediaAccessStatus('microphone');
  console.log(`Microphone privilege before applying: ${micPrivilege}`);
  if (micPrivilege !== 'granted') {
    await systemPreferences.askForMediaAccess('microphone');
    console.log('Requested microphone access from user');
  }
}

checkAndApplyDeviceAccessPrivilege();

Import dependencies

Import the modules and functions required to build the app using RTC SDK. Add the following code to renderer.js:

const {
  createAgoraRtcEngine,
  ChannelProfileType,
  ClientRoleType,
} = require("agora-electron-sdk");

Specify connection parameters

Provide the App ID, temporary token, and the channel name you used when generating the token. The engine uses these values to initialize and join the channel.

// Enter your App ID
const APPID = "<-- Insert App Id -->";
// Enter your temporary token
let token = "<-- Insert Token -->";
// Enter the channel name used when generating the token
const channel = "<-- Insert Channel Name -->";
// Specify a unique user ID for this session
let uid = 123;

Initialize the engine

For real-time communication, create an IRtcEngine object by calling createAgoraRtcEngine and then call initialize with RtcEngineContext to specify the App ID. Call registerEventHandler to register a custom event handler for managing user interactions within the channel.

let rtcEngine;
const os = require("os");
const path = require("path");
const sdkLogPath = path.resolve(os.homedir(), "./test.log");

// Create RtcEngine instance
rtcEngine = createAgoraRtcEngine();

// Initialize RtcEngine instance
rtcEngine.initialize({
  appId: APPID,
  logConfig: { filePath: sdkLogPath }
});

Join a channel

To join a channel, call joinChannel with the following parameters:

• Channel name: The name of the channel to join. Clients that pass the same channel name join the same channel. If a channel with the specified name does not exist, it is created when the first user joins.

• Authentication token: A dynamic key that authenticates a user when the client joins a channel. In a production environment, you obtain a token from a token server in your security infrastructure. For the purpose of this guide Generate a temporary token.

• User ID: A 32-bit signed integer that identifies a user in the channel. You can specify a unique user ID for each user yourself. If you set the user ID to 0 when joining a channel, the SDK generates a random number for the user ID and returns the value in the onJoinChannelSuccess callback.

• Channel media options: Configure ChannelMediaOptions to define publishing and subscription settings, optimize performance for your specific use-case, and set optional parameters.

For Voice Calling, set the channelProfile to ChannelProfileCommunication and the clientRoleType to ClientRoleBroadcaster.

// Join the channel using a temporary token
rtcEngine.joinChannel(token, channel, uid, {
  // Set the channel profile to communication
  channelProfile: ChannelProfileType.ChannelProfileCommunication,
  // Set the user role to broadcaster; keep the default value for audience role
  clientRoleType: ClientRoleType.ClientRoleBroadcaster,
  // Publish audio collected from the microphone
  publishMicrophoneTrack: true,
  // Automatically subscribe to all audio streams
  autoSubscribeAudio: true,
});

Register event handlers

Call the registerEventHandler method to register the following callback events:

• onJoinChannelSuccess: Triggered when the local user successfully joins a channel.
• onUserJoined: Triggered when a remote user joins the current channel.
• onUserOffline: Triggered when a remote user leaves the current channel.

const EventHandles = {
  // Listen for the local user joining the channel
  onJoinChannelSuccess: ({ channelId, localUid }, elapsed) => {
    console.log('Successfully joined channel: ' + channelId);
  },

  // Listen for remote users joining the channel
  onUserJoined: ({ channelId, localUid }, remoteUid, elapsed) => {
    console.log('Remote user ' + remoteUid + ' joined');
  },

  // Listen for users leaving the channel
  onUserOffline: ( { channelId, localUid }, remoteUid, reason ) => {
    console.log('Remote user ' + remoteUid + ' left the channel');
  },
};

// Register the event handler
rtcEngine.registerEventHandler(EventHandles);

Start and close the app

When a user launches your app, start Voice Calling. When a user closes the app, stop Voice Calling and release resources.

1. To start Voice Calling, initialize the engine and join a channel.

2. When Voice Calling ends, leave the channel and clean up resources:

   // Leave the channel
   rtcEngine.leaveChannel();

   When you no longer need to interact, unregister the event handler and call release to release engine resources.

   // Unregister the event handler
   rtcEngine.unregisterEventHandler(EventHandles);
   // Release the engine
   rtcEngine.release();

   After destroying the engine, you can no longer use SDK methods and callbacks. To use the real-time interaction functions again, create a new engine instance. See Initialize the engine for details.

Complete sample code

A complete code sample demonstrating the basic process of real-time interaction is provided for your reference. Replace the entire contents of the main.js and renderer.js with the following code samples:

main.js

To test the complete code, see Test the sample code.

Create a user interface

To create a minimal interface, add the following code to index.html: Sample code to create the user interface

<!DOCTYPE html>
<html>
 <head>
  <meta charset="UTF-8" />
  <title>Electron Voice Quickstart</title>
 </head>
 <body>
  <h1>Electron Voice Quickstart</h1>
 </body>
 <script src="./renderer.js"></script>
</html>

Test the sample code

Take the following steps to test the sample code:

1. Update the APPID, token, and channel parameter values in your code.

2. To run the app, execute the following command in the project root directory:

   npm start

3. Invite a friend to run the demo app on a second device. Alternatively, use the Web demo to join the same channel.

   • If users on both devices join the channel as hosts, they can hear each other.
   • If one user joins as host and the other as audience, the audience can hear the host.

Reference

This section contains content that completes the information on this page, or points you to documentation that explains other aspects to this product.

• If a firewall is deployed in your network environment, refer to Connect with Cloud Proxy to use Agora services normally.

Next steps

After implementing the quickstart sample, read the following documents to learn more:

• To ensure communication security in a test or production environment, best practice is to obtain and use a token from an authentication server. For details, see Secure authentication with tokens.

Sample project

Agora provides open source sample projects on GitHub for your reference. Download or view the JoinChannelAudio project for a more detailed example.

API Reference

• createAgoraRtcEngine

• joinChannel

• IRtcEngineEventHandler

• leaveChannel

• release

Frequently asked questions

• How can I listen for audience joining or leaving a channel?
• How can I solve channel-related issues?
• How can I set the log file?

See also

• Error codes

• Connection status management