How to test RtcTokenBuilder?

[agoraio]

How to test RtcTokenBuilder?

[plutoless]

unlike jwt token. you cannot parse a token back to readable information. is there any reason you want to do that?

[nilsreichardt]

Yes, I want to write a test similar I showed in the description. I want to call a method with my parameters and this method returns a token. After that I want to check if in this token are my passed parameters, like uid, role, channelName, etc.

[plutoless]

@nilsreichardt unfortunately you can't do that. we compare your token by generating a token using same algorithm and parameters and compare them. we don't convert it back to raw info either. As long as you are using our original algorithm and correct parameter, the token generated should be correct.

[0xdevalias]

@nilsreichardt I haven't verified this when running, but looking at the source..

We can see the source for buildTokenWithAccount here:

• Tools/DynamicKey/AgoraDynamicKey/nodejs/src/RtcTokenBuilder.js

  Lines 60 to 71 in a27ccdd

  	static buildTokenWithAccount(appID, appCertificate, channelName, account, role, privilegeExpiredTs) {
  	this.key = new AccessToken(appID, appCertificate, channelName, account)
  	this.key.addPriviledge(Priviledges.kJoinChannel, privilegeExpiredTs)
  	if (role == Role.ATTENDEE ||
  	role == Role.PUBLISHER ||
  	role == Role.ADMIN) {
  	this.key.addPriviledge(Priviledges.kPublishAudioStream, privilegeExpiredTs)
  	this.key.addPriviledge(Priviledges.kPublishVideoStream, privilegeExpiredTs)
  	this.key.addPriviledge(Priviledges.kPublishDataStream, privilegeExpiredTs)
  	}
  	return this.key.build();
  	}

It uses AccessToken, which is defined at:

• https://github.com/AgoraIO/Tools/blob/a27ccdd7bf29463f2755c8fa16e82efc1a366f59/DynamicKey/AgoraDynamicKey/nodejs/src/AccessToken.js

You can see the build function within this, that returns version + token.appID + content.toString('base64'):

• Tools/DynamicKey/AgoraDynamicKey/nodejs/src/AccessToken.js

  Lines 23 to 46 in a27ccdd

  	this.build = function () {
  	var m = Message({
  	salt: token.salt
  	, ts: token.ts
  	, messages: token.messages
  	}).pack();
  	var toSign = Buffer.concat(
  	[Buffer.from(token.appID, 'utf8'),
  	Buffer.from(token.channelName, 'utf8'),
  	Buffer.from(token.uid, 'utf8'),
  	m]);
  	var signature = encodeHMac(token.appCertificate, toSign);
  	var crc_channel = UINT32(crc32.str(token.channelName)).and(UINT32(0xffffffff)).toNumber();
  	var crc_uid = UINT32(crc32.str(token.uid)).and(UINT32(0xffffffff)).toNumber();
  	var content = AccessTokenContent({
  	signature: signature,
  	crc_channel: crc_channel,
  	crc_uid: crc_uid,
  	m: m
  	}).pack();
  	return (version + token.appID + content.toString('base64'));
  	}

There is also the fromString function defined in that same file:

• Tools/DynamicKey/AgoraDynamicKey/nodejs/src/AccessToken.js

  Lines 52 to 79 in a27ccdd

  	this.fromString = function (originToken) {
  	try {
  	originVersion = originToken.substr(0, VERSION_LENGTH);
  	if (originVersion != version) {
  	return false;
  	}
  	var originAppID = originToken.substr(VERSION_LENGTH, (VERSION_LENGTH + APP_ID_LENGTH));
  	var originContent = originToken.substr((VERSION_LENGTH + APP_ID_LENGTH));
  	var originContentDecodedBuf = Buffer.from(originContent, 'base64');
  	var content = unPackContent(originContentDecodedBuf);
  	this.signature = content.signature;
  	this.crc_channel_name = content.crc_channel_name;
  	this.crc_uid = content.crc_uid;
  	this.m = content.m;
  	var msgs = unPackMessages(this.m);
  	this.salt = msgs.salt;
  	this.ts = msgs.ts;
  	this.messages = msgs.messages;
  	} catch (err) {
  	console.log(err);
  	return false;
  	}
  	return true;
  	};

Based on that, it looks like you should be able to recover some, if not most/all of the parameters you want, and thus be able to write some tests for them.

Let me know how you go with this, would be interested to hear!

@plutoless is there documentation or can you clarify the details on the tokenbuilder. I am specifically looking for the difference between the below two methods. C# example..

What is this property does this._salt = salt;?

 public AccessToken(string appId, string appCertificate, string channelName, string uid)
        {
            _appId = appId;
            _appCertificate = appCertificate;
            _channelName = channelName;
            _uid = uid;
        }

        public AccessToken(string appId, string appCertificate, string channelName, string uid, uint ts, uint salt)
        {
            this._appId = appId;
            this._appCertificate = appCertificate;
            this._channelName = channelName;
            this._uid = uid;
            this._ts = ts;
            this._salt = salt;
        }