I'm having difficulty identifying which track belongs to which media source on the receiving end. In unified plan is there any way to define custom properties on a transceiver?
I'm having difficulty identifying which track belongs to which media source on the receiving end.
Use transceiver.mid or the stream.id of an associated stream to correlate tracks.
A transceiver has a mid, which is a unique id that is the same on both sides of the connection after initial negotiation. It is exposed here:
pc.ontrack = event => {
const track = event.track;
const mid = event.transceiver.mid;
}
Alternatively, use addTransceiver(track, {streams: [stream]}) or addTrack(track, stream) and use the stream.id:
pc.ontrack = event => {
const track = event.track;
const id = event.streams[0].id;
}
In unified plan is there any way to define custom properties on a transceiver?
Any JS object can have a property defined on it. But I suspect that's not what you mean.
mid and stream.ids are the only metadata negotiated over to the remote peer connection, and there's no official way to add custom ones.
Once a connection has been established, you can of course use a datachannel to send whatever data you want over.
How to hack custom metadata
OK there is a way, but I hesitate to show it, since you haven't said what you'd use it for. Please consider the above options before resorting to this. Use at your own risk!
You can add any number of stream.ids and replace them in the SPD with whatever you want:
const config = {sdpSemantics: "unified-plan"};
const pc1 = new RTCPeerConnection(config), pc2 = new RTCPeerConnection(config);
const stream = new MediaStream();
pc1.addTransceiver("video", {streams: [stream]});
pc1.msg = "Hello";
pc2.ontrack = event => {
pc2.msg = event.streams[0].id;
console.log(pc2.msg);
};
pc1.onicecandidate = e => pc2.addIceCandidate(e.candidate);
pc2.onicecandidate = e => pc1.addIceCandidate(e.candidate);
pc1.onnegotiationneeded = async e => {
await pc1.setLocalDescription(await pc1.createOffer());
let sdp = pc1.localDescription.sdp.replace(new RegExp(stream.id, 'g'), pc1.msg);
await pc2.setRemoteDescription({type: "offer", sdp});
await pc2.setLocalDescription(await pc2.createAnswer());
await pc1.setRemoteDescription(pc2.localDescription);
}
I'm not actually recommending this, just showing it can be done. Any message you put in here is subject to SDP parsing rules, so be careful.
Related
After a night of trial and error I have decided on a much simpler way to explain my issue. Again, I have no JS experience, so I don't really know what I am doing.
I have 5 classes:
game - holds information about my games
classification - holds information about the user classes available in games
game_classifications - creates a one game to many classifications relationship (makes a game have mulitple classes)
mission - holds my mission information
mission_class - creates a one to many relationship between a mission and the classes available for that mission
Using Cloud Code, I want to provide two inputs through my Rest API being missionObjectId and gameObjectId.
The actual steps I need the code to perform are:
Get the two inputs provided {"missionObjectId":"VALUE","gameObjectId":"VALUE"}
Search the game_classifications class for all records where game = gameObjectID
For each returned record, create a new record in mission_class with the following information:
mission_id = missionObjectId
classification = result.classification
Here is an image of the tables:
And here is how I have tried to achieve this:
Parse.Cloud.define("activateMission", async (request) => {
Parse.Cloud.useMasterKey();
const query = new Parse.query('game_classifications');
query.equalTo("gameObjectId", request.params.gameObjectId);
for (let i = 0; i < query.length; i ++) {
const mission_classification = Parse.Object.extend("mission_class");
const missionClass = new mission_classification();
missionClass.set("mission_id", request.params.missionObjectId);
missionClass.set("classification_id", query[i].classificationObjectId);
return missionClass.save();
}
});
Does anyone have any advice or input that might help me achieve this goal?
The current error I am getting is:
Parse.query is not a constructor
Thank you all in advance!
Some problems on your current code:
Parse.Cloud.useMasterKey() does not exist for quite a long time. Use useMasterKey option instead.
It's Parse.Query and not Parse.query.
You need to run query.findAll() command and iterate over it (and not over query).
For performance, move Parse.Object.extend calls to the beginning of the file.
To access the field of an object, use obj.get('fieldName') and not obj.fieldName.
If you return the save operation, it will save the first object, return, and not save the others.
So, the code needs to be something like this:
const mission_classification = Parse.Object.extend("mission_class");
const game = Parse.Object.extend("game");
Parse.Cloud.define("activateMission", async (request) => {
const query = new Parse.Query('game_classifications');
const gameObj = new game();
gameObj.id = request.params.gameObjectId;
query.equalTo("gameObjectId", gameObj);
const queryResults = await query.findAll({useMasterKey: true});
for (let i = 0; i < queryResults.length; i++) {
const missionClass = new mission_classification();
missionClass.set("mission_id", request.params.missionObjectId);
missionClass.set("classification_id", queryResults[i].get('classificationObjectId'));
await missionClass.save(null, { useMasterKey: true });
}
});
When I add bot.hears(...), it registers middleware for handling matching text messages. But now it will handle those messages even if they are sent any time, even if not expected.
So if I am creating a stateful service, I would like to listen to particular messages only at appropriate time.
How can I unregister middleware, so that it does not hear any more previously handled messages?
I turned out I was looking for Scenes. How to use them is described on Github.
I'll just post a slightly modified code from the links above:
const { Telegraf, Scenes, session } = require('telegraf')
const contactDataWizard = new Scenes.WizardScene(
'CONTACT_DATA_WIZARD_SCENE_ID', // first argument is Scene_ID, same as for BaseScene
(ctx) => {
ctx.reply('Please enter guest\'s first name', Markup.removeKeyboard());
ctx.wizard.state.contactData = {};
return ctx.wizard.next();
},
(ctx) => {
// validation example
if (ctx.message.text.length < 2) {
ctx.reply('Please enter real name');
return;
}
ctx.wizard.state.contactData.firstName = ctx.message.text;
ctx.reply('And last name...');
return ctx.wizard.next();
},
);
const stage = new Scenes.Stage();
stage.register(contactDataWizard);
bot.use(session());
bot.use(stage.middleware());
But I still don't know how to generally implement it, so I need to find it out in the Scenes code of Telegraf.
I'm trying to use hyperdb in browser with swarming via webrtc and signalhub. The code is pretty strait forward, but there is some issue with hyperdb replicate where the connecting is killed because of a sameKey check in hypercore. So, I'm thinking ... I'm not properly juggling my discovery keys and id keys so the peers know they should be sync'd. Here is some sample code, it is a bit of a mess but the relevant bits are the hyperdb initialization and the webrtc/signalhub stuff (I think) ... the key at the top is the discovery key of the other peer:
const crypto = require('crypto'),
sha = crypto.createHash('sha1'),
hyperdb = require('hyperdb'),
hyperdiscovery = require('hyperdiscovery'),
cms = require('random-access-idb')('cms'),
webrtc = require('webrtc-swarm'),
signalhub = require('signalhub'),
hyperdrive = require('hyperdrive'),
pump = require('pump');
// Discovery key of other peer/signalhub channel
var key = "cbffda913dabfe73cbd45f64466ffda845383965e66b2aef5f3b716ee6c06528";
const db = hyperdb(filename => {
return cms(filename);
}, { valueEncoding: 'utf-8' });
var DEFAULT_SIGNALHUBS = 'https://signalhub-jccqtwhdwc.now.sh';
db.on('ready', function () {
const swarm = webrtc(signalhub(key, DEFAULT_SIGNALHUBS));
swarm.on('peer', function (conn) {
console.log("PEER!!!!!!!");
const peer = db.replicate({
upload: true,
download: true
});
pump(conn, peer, conn)
});
});
I put up a working example here: https://github.com/joehand/hyperdb-web-example/blob/master/index.js
I think you are getting that error because you are not initializing the db with the key:
var db = hyperdb(storage, key)
Once you do that, you can get the discovery key. Generally, you don't need to be copying the discovery key around because that is always generated from the public key.
If that does not work, please include only the relevant code or a minimum example, so it is easier to debug =). Thanks!
I am a newbie to WebRTC. I am building an application that enables users to view each other's video stream, as well as exchange files. The audio/video part is implemented and working. The problem is I need to add the ability to exchange files now. I am using the below code to initialize the PeerConnection object
var connection = _getConnection(partnerId);
console.log("Initiate offer")
// Add our audio/video stream
connection.addStream(stream);
// Send an offer for a connection
connection.createOffer(function (desc) { _createOfferSuccess(connection, partnerId, desc) }, function (error) { console.log('Error creating session description: ' + error); });
_getConnection creates a new RTCPeerConnection object using
var connection = new RTCPeerConnection(iceconfig);
i.e., with no explicit constraints. It also initializes the different event handlers on it. Right after this, I attach the audio/video stream to this connection. I also cache these connections using the partner id, so I can use it later.
The question is, can I later recall the connection object from the cache, add a data channel to it using something like
connection.createDataChannel("DataChannel", dataChannelOptions);
And use it to share files, or do I have to create a new RTCPeerConnection object and attach the data channel to it?
You certainly do not have to create a another PeerConnection for file transfer alone. Existing PeerConnection can utilize RTCDatachannel with behaves like traditional websocket mechanism ( ie 2 way communication without a central server )
`var PC = new RTCPeerConnection();
//specifying options for my datachannel
var dataChannelOptions = {
ordered: false, // unguaranted sequence
maxRetransmitTime: 2000, // 2000 miliseconds is the maximum time to try and retrsanmit failed messages
maxRetransmits : 5 // 5 is the number of times to try to retransmit failed messages , other options are negotiated , id , protocol
};
// createing data channel using RTC datachannel API name DC1
var dataChannel = PC.createDataChannel("DC1", dataChannelOptions);
dataChannel.onerror = function (error) {
console.log("DC Error:", error);
};
dataChannel.onmessage = function (event) {
console.log("DC Message:", event.data);
};
dataChannel.onopen = function () {
dataChannel.send(" Sending 123 "); // you can add file here in either strings/blob/array bufers almost anyways
};
dataChannel.onclose = function () {
console.log("DC is Closed");
};
`
PS : while sending files over datachannel API , it is advisable to break down the files into small chunks beforehand . I suggest chunk size of almost 10 - 15 KB .
I'm looking into using a javascript logging framework in my app.
I quite like the look of log4javascript (http://log4javascript.org/) but I have one requirement which I'm not sure that it satisfies.
I need to be able to ask the framework for all messages which have been logged.
Perhaps I could use an invisible InPageAppender (http://log4javascript.org/docs/manual.html#appenders) to log to a DOM element, then scrape out the messages from that DOM element - but that seems pretty heavy.
Perhaps I need to write my own "InMemoryAppender"?
There's an ArrayAppender used in log4javascript's unit tests that stores all log messages it receives in an array accessible via its logMessages property. Hopefully it should show up in the main distribution in the next version. Here's a standalone implementation:
var ArrayAppender = function(layout) {
if (layout) {
this.setLayout(layout);
}
this.logMessages = [];
};
ArrayAppender.prototype = new log4javascript.Appender();
ArrayAppender.prototype.layout = new log4javascript.NullLayout();
ArrayAppender.prototype.append = function(loggingEvent) {
var formattedMessage = this.getLayout().format(loggingEvent);
if (this.getLayout().ignoresThrowable()) {
formattedMessage += loggingEvent.getThrowableStrRep();
}
this.logMessages.push(formattedMessage);
};
ArrayAppender.prototype.toString = function() {
return "[ArrayAppender]";
};
Example use:
var log = log4javascript.getLogger("main");
var appender = new ArrayAppender();
log.addAppender(appender);
log.debug("A message");
alert(appender.logMessages);