SIP Library for JavaScript

Create real-time peer-to-peer audio and video sessions via WebRTC
Utilize SIP in your web application via SIP over WebSocket
Send instant messages and view presence
Support early media, hold and transfers
Send DTMF RFC 2833 or SIP INFO
Share your screen or desktop
Written in TypeScript
Runs in all major web browsers
Compatible with standards compliant servers including Asterisk and FreeSWITCH

Demo

Want see it in action? The project website, sipjs.com, has a live demo.

Looking for code to get started with? This repository includes demonstrations which run in a web browser.

Usage

To place a SIP call, either utilize the SimpleUser class...

import { Web } from "sip.js";

// Helper function to get an HTML audio element
function getAudioElement(id: string): HTMLAudioElement {
  const el = document.getElementById(id);
  if (!(el instanceof HTMLAudioElement)) {
    throw new Error(`Element "${id}" not found or not an audio element.`);
  }
  return el;
}

// Options for SimpleUser
const options: Web.SimpleUserOptions = {
  aor: "sip:alice@example.com", // caller
  media: {
    constraints: { audio: true, video: false }, // audio only call
    remote: { audio: getAudioElement("remoteAudio") } // play remote audio
  }
};

// WebSocket server to connect with
const server = "wss://sip.example.com";

// Construct a SimpleUser instance
const simpleUser = new Web.SimpleUser(server, options);

// Connect to server and place call
simpleUser.connect()
  .then(() => simpleUser.call("sip:bob@example.com"))
  .catch((error: Error) => {
    // Call failed
  });

Or, alternatively, use the full API framework...

import { Inviter, SessionState, UserAgent } from "sip.js";

// Create user agent instance (caller)
const userAgent = new UserAgent({
  uri: UserAgent.makeURI("sip:alice@example.com"),
  transportOptions: {
    server: "wss://sip.example.com"
  },
});

// Connect the user agent
userAgent.start().then(() => {

  // Set target destination (callee)
  const target = UserAgent.makeURI("sip:bob@example.com");
  if (!target) {
    throw new Error("Failed to create target URI.");
  }

  // Create a user agent client to establish a session
  const inviter = new Inviter(userAgent, target, {
    sessionDescriptionHandlerOptions: {
      constraints: { audio: true, video: false }
    }
  });

  // Handle outgoing session state changes
  inviter.stateChange.addListener((newState) => {
    switch (newState) {
      case SessionState.Establishing:
        // Session is establishing
        break;
      case SessionState.Established:
        // Session has been established
        break;
      case SessionState.Terminated:
        // Session has terminated
        break;
      default:
        break;
    }
  });

  // Send initial INVITE request
  inviter.invite()
    .then(() => {
      // INVITE sent
    })
    .catch((error: Error) => {
      // INVITE did not send
    });

});

Installation

Node module

npm install sip.js

UMD bundle

Download sipjs.com/download
CDN jsDelivr.com

Building, Development and Testing

Clone this repository, then...

npm install
npm run build-and-test

For more info please see the Documentation.

Support