RingCentral Softphone SDK for TypeScript

This is a TypeScript SDK for RingCentral Softphone. It is a complete rewrite of the RingCentral Softphone SDK for JavaScript

Users are recommended to use this SDK instead of the JavaScript SDK.

Installation

yarn install ringcentral-softphone

Where to get credentials?

Manually

1. Login to https://service.ringcentral.com
2. Find the user/extension you want to use
3. Check the user's "Devices & Numbers"
4. Find a phone/device that you want to use
5. if there is none, you need to create one. Check steps below for more details
6. Click the "Set Up and Provision" button
7. Click the link "Set up manually using SIP"
8. You will find "SIP Domain", "Outbound Proxy", "User Name", "Password" and "Authorization ID"

Please note that, "SIP Domain" name should come without port number. I don't know why it shows a port number on the page. This SDK requires a "domain" which is "SIP Domain" but without the port number.

Programmatically

Invoke this RESTful API: https://developers.ringcentral.com/api-reference/Devices/readDeviceSipInfo

Please note that, in order to invoke this API, you need to be familiar with RingCentral RESTful programmming.

Here is a demo: https://github.com/tylerlong/rc-get-device-info-demo/blob/main/src/demo.ts

The credentials data returned by that API is like this:

{
  "domain": "sip.ringcentral.com",
  "outboundProxies": [
    {
      "region": "EMEA",
      "proxy": "sip40.ringcentral.com:5090",
      "proxyTLS": "sip40.ringcentral.com:5096"
    },
    {
      "region": "APAC",
      "proxy": "sip71.ringcentral.com:5090",
      "proxyTLS": "sip71.ringcentral.com:5096"
    },
    {
      "region": "APAC",
      "proxy": "sip60.ringcentral.com:5090",
      "proxyTLS": "sip60.ringcentral.com:5096"
    },
    {
      "region": "EMEA",
      "proxy": "sip30.ringcentral.com:5090",
      "proxyTLS": "sip30.ringcentral.com:5096"
    },
    {
      "region": "APAC",
      "proxy": "sip70.ringcentral.com:5090",
      "proxyTLS": "sip70.ringcentral.com:5096"
    },
    {
      "region": "APAC",
      "proxy": "sip50.ringcentral.com:5090",
      "proxyTLS": "sip50.ringcentral.com:5096"
    },
    {
      "region": "NA",
      "proxy": "SIP10.ringcentral.com:5090",
      "proxyTLS": "sip10.ringcentral.com:5096"
    },
    {
      "region": "NA",
      "proxy": "SIP20.ringcentral.com:5090",
      "proxyTLS": "sip20.ringcentral.com:5096"
    },
    {
      "region": "LATAM",
      "proxy": "sip80.ringcentral.com:5090",
      "proxyTLS": "sip80.ringcentral.com:5096"
    }
  ],
  "userName": "16501234567",
  "password": "password",
  "authorizationId": "802512345678"
}

You will need to choose a outboundProxy value based on your location. And please choose the proxyTLS value because this SDK uses TLS. For example if you live in north America, choose sip10.ringcentral.com:5096.

Usage

import Softphone from 'ringcentral-softphone';

const softphone = new Softphone({
  domain: process.env.SIP_INFO_DOMAIN,
  outboundProxy: process.env.SIP_INFO_OUTBOUND_PROXY,
  username: process.env.SIP_INFO_USERNAME,
  password: process.env.SIP_INFO_PASSWORD,
  authorizationId: process.env.SIP_INFO_AUTHORIZATION_ID,
});

For complete examples, see demos/

Supported features

• inbound call
• outbound call
• inbound DTMF
• outbound DTMF
• reject inbound call
• cancel outbound call
• hang up ongoing call
• receive audio stream from peer
• stream local audio to remote peer
• call transfer

Notes

Audio formats

The codec used between server and client is "OPUS/16000". This SDK will auto decode/encode the codec to/from "uncompressed PCM".

Bit rate is 16, which means 16 bits per sample. Sample rate is 16000, which means 16000 samples per second. Encoding is "signed-integer".

You may play saved audio by the following command:

play -t raw -b 16 -r 16000 -e signed-integer test.wav

To stream an audio file to remote peer, you need to make sure that the audio file is playable by the command above.

ffmpeg

If you prefer ffmpeg, here is the command to play the file:

ffplay -autoexit -f s16le -ar 16000 test.wav

how to generate audio file for testing

On macOS:

say "Hello world" -o test.wav --data-format=LEI16@16000

For Linux and Windows, please do some investigation yourself. Audio file generation is out of scope of this SDK.

Multiple instances with same credentials

You can run multiple softphone instances with the same credentials without encountering any errors. However, only the most recent instance will receive inbound calls.

In the future, we may consider supporting multiple active instances using the same credentials. For now, we believe there is no demand for this functionality.

Invalid callee number

If you call an invalid number. The sip server will return "SIP/2.0 486 Busy Here".

This SDK will emit a "busy" event for the call session and dispose it.

You can detect such an event by:

callSession.once('busy', () => {
  console.log('cannot reach the callee number');
});

Pipe a call session to another

When you get audio from a call session, you may forward it to another call session:

callSession1.on('rtpPacket', (rtpPacket: RtpPacket) => {
  if (rtpPacket.header.payloadType === 109) {
    // 109 is for opus audio packet
    callSession2.sendPacket(rtpPacket);
  }
});

Todo

• Make codec configurable

---

Dev Notes

Content below is for the maintainer of this SDK.

• We don't need to explicitly tell remote server our local UDP port (for audio streaming) via SIP SDP message. We send a RTP message to the remote server first, so the remote server knows our IP and port. So, the port number in SDP message could be fake.
• Ref: https://www.ietf.org/rfc/rfc3261.txt
• Caller Id feature is not supported. P-Asserted-Identity doesn't work. I think it is by design, since hardphone cannot support it.