feat: Add PlaybackGrant.

[sarahcstringer]

Fixes

Adds PlaybackGrants.

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[stern-shawn]

🚢 🇮🇹

[stern-shawn]

Based on this sample from the test, I think we should look into typing grant more specifically since object is a very loose definition.

var playbackGrant = {
  requestCredentials: null,
  playbackUrl: 'https://000.us-east-1.playback.live-video.net/api/video/v1/us-east-000.channel.000?token=xxxxx',
  playerStreamerSid: 'VJXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX',
};

var grant = new twilio.jwt.AccessToken.PlaybackGrant();
grant.grant = playbackGrant;

Maybe a new interface to DRY things up?:

export interface PlaybackGrantResponse {
  requestCredentials: string | null;
  playbackUrl: string;
  playerStreamerSid: string;
}

[shwetha-manvinkurke]

+1. Also need to do the same in other languages.

[sarahcstringer]

Thanks so much for the suggestion -- we chatted and are planning to do this step in a separate PR, to speed up getting these into the helper libraries. But definitely going to make a new PR to clean this up.

[miguelgrinberg]

The playback grant is supposed to be an opaque object returned by a Live API, none of these fields have to be provided by the developer. While adding typing seems like a good idea in principle, this is going to break if/when the Twilio Live team decide to make changes to the format of the grant, like maybe add a new field. I'm not really sure what the best option is, just wanted to point out that there are downsides to adding typing about private attributes of the grant.

[sarahcstringer]

I was able to verify here that I could add a PlaybackGrant to a token and connect with it:

const AccessToken = require('twilio').jwt.AccessToken;
const PlaybackGrant = AccessToken.PlaybackGrant;

const playbackGrant = new PlaybackGrant({
  grant: {'requestCredentials': null,
 'playbackUrl': 'https:/...',
 'playerStreamerSid': 'VJXXX'}
});

const token = new AccessToken(
  twilioAccountSid,
  twilioApiKey,
  twilioApiSecret
);
token.addGrant(playbackGrant);

// Serialize the token to a JWT string
console.log(token.toJwt());