@twilio/voice-sdk/lib/twilio/rtc/icecandidate.ts

Twilio's JavaScript Voice SDK

/**
 * Payload object we send to insights
 * @private
 */
interface RTCIceCandidatePayload {
  candidate_type: string;
  // Deprecated by newer browsers. Will likely not show on most recent versions of browsers.
  deleted: boolean;
  ip: string;
  is_remote: boolean;
  'network-cost': number | undefined;
  port: number;
  priority: number;
  protocol: string;
  related_address: string;
  related_port: number;
  tcp_type: string;
  transport_id: string;
}

/**
 * Represents an ICE candidate coming from the browser
 * https://developer.mozilla.org/en-US/docs/Web/API/RTCIceCandidate
 * @private
 */
export type RTCIceCandidate = any;

/**
 * {@link RTCIceCandidate} parses an ICE candidate gathered by the browser
 * and returns a IceCandidate object
 */
export class IceCandidate {
  /**
   * Candidate's type
   * https://developer.mozilla.org/en-US/docs/Web/API/RTCIceCandidateType
   */
  private candidateType: string;

  /**
   * Whether this is deleted from the list of candidate gathered
   */
  private deleted: boolean = false;

  /**
   * Candidate's IP address
   */
  private ip: string;

  /**
   * Whether this is a remote candidate
   */
  private isRemote: boolean;

  /**
   * A number from 0 to 999 indicating the cost of network
   * where larger values indicate a stronger preference for not using that network
   */
  private networkCost: number | undefined;

  /**
   * Candidate's port number
   */
  private port: number;

  /**
   * A number indicating candidate's priority
   */
  private priority: number;

  /**
   * Candidate's protocol - udp or tcp
   */
  private protocol: string;

  /**
   * The host candidate's IP address if the candidate is derived from another candidate,
   */
  private relatedAddress: string;

  /**
   * The port number of the candidate from which this
   * candidate is derived, such as a relay or reflexive candidate.
   */
  private relatedPort: number;

  /**
   * Represents the type of TCP candidate.
   */
  private tcpType: string;

  /**
   * Also known as sdpMid, specifying the candidate's media stream identification tag which uniquely
   * identifies the media stream within the component with which the candidate is associated
   */
  private transportId: string;

  /**
   * @constructor
   * @param iceCandidate RTCIceCandidate coming from the browser
   */
  constructor(iceCandidate: RTCIceCandidate, isRemote: boolean = false) {
    let cost;
    const parts = iceCandidate.candidate.split('network-cost ');

    if (parts[1]) {
      cost = parseInt(parts[1], 10);
    }

    this.candidateType = iceCandidate.type;
    this.ip = iceCandidate.ip || iceCandidate.address;
    this.isRemote = isRemote;
    this.networkCost = cost;
    this.port = iceCandidate.port;
    this.priority = iceCandidate.priority;
    this.protocol = iceCandidate.protocol;
    this.relatedAddress = iceCandidate.relatedAddress;
    this.relatedPort = iceCandidate.relatedPort;
    this.tcpType = iceCandidate.tcpType;
    this.transportId = iceCandidate.sdpMid;
  }

  /**
   * Get the payload object for insights
   */
  toPayload(): RTCIceCandidatePayload {
    return {
      'candidate_type': this.candidateType,
      'deleted': this.deleted,
      'ip': this.ip,
      'is_remote': this.isRemote,
      'network-cost': this.networkCost,
      'port': this.port,
      'priority': this.priority,
      'protocol': this.protocol,
      'related_address': this.relatedAddress,
      'related_port': this.relatedPort,
      'tcp_type': this.tcpType,
      'transport_id': this.transportId,
    };
  }
}