I am trying to make a chat system where only two users are able to talk to each other at a time ( much like facebook's chat )
I've tried multiplexing, using mongoDB's _id as the name so every channel is unique.
The problem I'm facing is that I cannot direct a message to a single client connection.
this is the client side code that first sends the message
$scope.sendMessage = function() {
specificChannel.send(message)
$scope.messageText = '';
};
this is the server side receiving the message
specificChannel.on('connection', function (conn) {
conn.on('data', function(message){
conn.write('message')
}
}
When I send a message, to any channel, every channel still receives the message.
How can I make it so that each client only listens to the messages sent to a specific channel?
It appeared that SockJS doesn't support "private" channels. I used the following solution for a similar issue:
var channel_id = 'my-very-private-channel'
var connection = new SockJS('/pubsub', '')
connection.onopen = function(){
connection.send({'method': 'set-channel', 'data': {'channel': channel_id}})
}
Backend solution is specific for every technology stack so I can't give a universal solution here. General idea is the following:
1) Parse the message in "on_message" function to find the requested "method name"
2) If the method is "set-channel" -> set the "self.channel" to this value
3) Broadcast further messages to subscribers with the same channel (I'm using Redis for that, but it also depends on your platform)
Hope it helps!
Related
I want to have someone say to a bot in slack:
#Bot setup #usertosetup
This should then start a conversation with that user to be setup. If I'm right and I've read correctly, the one that starts the conversation with the bot will be the one it listens to?
So the flow would be to bring the new user, an admin and the bot into their own room on slack, then start the conversation. Ideally, would be if you could say in the main chat window that phrase and it starts a private message with the user to set up, but I don't think that's possible due to the channel not existing yet?
I'm using Botkit to get this done.
Solved it.
controller.hears('setup','direct_mention', function(bot,message) {
var x = message.text.indexOf("#");
var usr = message.text.substr(x - 2, message.text.length);
usr = usr.substring(3, usr.length - 1);
bot.api.im.open({user: usr}, function(err, response) {
bot.startConversation({
user:usr,
channel: response.channel.id
}, "Hello");
});
So, it finds the index of the message sent to the bot with the # symbol, pulls it out and does some substring fun to reduce it. Then, launches the conversation by the channel.
I'm trying to do some analytics on average response time from some of our users on Twilio Chat.
I'm iterating through my channels, and I'm able to pull the info about messages, so I can compare times a message went un-responded to. However, I can't determine which users were in the channel at that time.
Is there anything on the channel that would give me historic member data? Who was in the channel? The channel.messages().list() method is only giving me the text of the messages sent to the channel and who it was by, but the user who may have been in a channel to respond changes throughout a channel's life time.
This is on the backend using the node.js SDK. note: This isn't a complete implementation for what I'm trying to do, but taking it in steps to get access to the information I'd need to do this. Once I have these messages and know which users are supposed to be in a channel at a given time, I can do the analytics to see how long it took for the users I am looking for to respond.
var fs = require('fs');
const Twilio = require('twilio');
const client = new Twilio(env.TWILIO_ACCOUNT_SID, env.TWILIO_AUTH);
const service = client.chat.services(env.TWILIO_IPM_SERVICE_SID);
async function getChatMessages() {
const fileName = 'fileName.csv';
const getLine = message => {
return `${message.channelSid},${message.sid},${message.dateCreated},${message.from},${message.type},${message.body}\n`;
}
const writeToFile = message => { fs.appendFileSync(fileName, getLine(message)); };
const headerLine = `channelSid,messageSid,dateCreated,author,type,body`;
fs.writeFileSync(fileName, headerLine);
await service.channels.each(
async (channel, done) => {
i++;
let channelSid = channel.sid;
if( channel.messagesCount == 0 ) return;
try {
await channel.messages().list({limit:1000, order:"asc"}).then(
messages => {
messages.forEach( writeToFile );
}
);
} catch(e) {
console.log(`There was an error getting messages for ${channelSid}: ${e.toString()}`);
}
if( i >= max ) done();
}
);
}
I'm beginning to be resigned to the fact that maybe this would only have been possible to track had I set up the proper event listeners / webhooks to begin with. If that's the case, I'd like to know so I can get that set up. But, if there's any endpoint I can reach out to and see who was joining / leaving a channel, that would be ideal for now.
The answer is that unfortunately you can not get this data retroactively. Twilio offers a webhooks API for chat which you can use to track this data yourself as it happens, but if you don't capture the events, you do not get access to them again.
I'm trying to make a game, which works on rooms, lobby and such (imagine the chat app, except with additional checks/information storing).
Let's say, I have a module room.js
var EventEmitter = require('events');
class Room extends EventEmitter {
constructor (id, name) {
super();
this.id = id;
this.name = name;
this.users = [];
}
}
Room.prototype.addUser = function (user) {
if(this.users.indexOf(user) === -1) {
this.users.push(user);
this.emit('user_joined', user);
} else {
/* error handling */
}
};
module.exports = {
Room: Room,
byId: function (id) {
// where should I look up?
}
};
How can I get exactly this object (with events)? How can I access events emitted by this object?
In a single instance of node, I would do something like:
var rooms = [];
var room = new Room(1234, 'test room');
room.on('user_joined', console.log);
rooms.push(room);
Also, I don't quite understood how Redis is actually helping (is it replacement of EventEmitter?)
Regards.
EDIT: Would accept PM2 solutions too.
Instead of handling rooms in Node, you can replace them with channels in Redis).
When a new client wants to join in a room, the NodeJS app returns it the ID of this given room (that is to say the name of the channel), then the client suscribes to the selected room (your client is directly connected to Redis.
You can use a Redis Set to manage the list of rooms.
In this scenario, you don't need any event emitter, and your node servers are stateless.
Otherwise, it would mean Redis would be exposed on the Internet (assuming your game is public), so you must activate Redis authentication. A major problem with this solution is that you have to give the server password to all clients, so it's definitely unsecure.
Moreover, Redis' performances allow brute force attacks so exposing it on Internet is not recommended. That's why I think all communications should go through a Node instance, even if Redis is used as a backend.
To solve this, you can use socket.io to open sockets between Node and your clients, and make the Node instances (not the client) subscribe to the Redis channel. When a message is published by Redis, send it to the client through the socket. And add a layer of authentication to ensure only valid clients connect to a given channel.
Event emitter is not required. It's the Redis client which will be an event emitter (like in this example based on ioRedis)
I have a node.js running which the users will connect to. The offer and answer will be generated and sent through node.js.
I'm trying to establish a peer connection and send over a camera stream. I tried my code without using ICE candidates as the computers where in the same subnet. I tried to implement ICE afterwards. I'm not sure if i've done it right though or if it's even needed if the computers are on the same subnet.
var localStream;
//Connect to signaling server
var signalingChannel = io.connect('http://85.134.54.193:8001');
console.log("Connect to signaling server");
var servers = null;
var video1;
var video2;
var audio1;
var audio2;
var cfg = {"iceServers":[{"url":"stun:stun.l.google.com:19302"}]};//{ "iceServers": [{ "url": "stun:stun.l.google.com:19302" }] };
var con = { 'optional': [{'DtlsSrtpKeyAgreement': true}, {'RtpDataChannels': true }] };
var peerConnection;
//Runs after the page has been loaded
window.onload=function(){
//Gets ID for the video element which will display the local stream
video1 = document.getElementById("audio1");
//Gets ID for the video element which will display the remote stream
video2 = document.getElementById("audio2");
audio1 = document.getElementById("audio1");
audio2 = document.getElementById("audio2");
}
//Start button function
function caller(){
peerConnection = new webkitRTCPeerConnection(cfg);
navigator.webkitGetUserMedia({'audio':true, video:true}, function (stream) {
console.log("Got local audio", stream);
video1.src = window.webkitURL.createObjectURL(stream)
peerConnection.addStream(stream);
},
function ( err ) {
console.log( 'error: ', err );
});
console.log("Calling");
//Create Offer
peerConnection.createOffer(function (offerDesc) {
console.log("Created local offer", offerDesc.sdp);
peerConnection.setLocalDescription(offerDesc);
}, function () { console.warn("Couldn't create offer"); });
//ICE Candidates Generator
peerConnection.onicecandidate = function(evt) {
//When The Ice Gathering is complete
if (evt.target.iceGatheringState == "complete") {
//Create a new offer with ICE candidates
peerConnection.createOffer(function(offer) {
console.log("Offer with ICE candidates: " + offer.sdp);
signalingChannel.emit('offer', JSON.stringify(offer));
console.log("offer sent");
signalingChannel.on('answer', function(data){
console.log("Receive answer");
//The answer is set as the remote description for the offerer
peerConnection.setRemoteDescription(new RTCSessionDescription(JSON.parse(data)));
console.log("Set remote desc");
peerConnection.onaddstream = gotRemoteStream;
console.log("Add remote stream to peer connection");
});
});
}
}
}
function answerer(){
peerConnection = new webkitRTCPeerConnection(cfg);
navigator.webkitGetUserMedia({'audio':true, video:true}, function (stream) {
console.log("Got local audio", stream);
video1.src = window.webkitURL.createObjectURL(stream)
peerConnection.addStream(stream);
},
function ( err ) {
console.log( 'error: ', err );
});
console.log("Answering");
//Listen for offer
signalingChannel.on('offer', function(data){
console.log("Offer Received");
//Set the remote description from caller's local description
peerConnection.setRemoteDescription(new RTCSessionDescription(JSON.parse(data)));
//Generate answer after getting the remote description
peerConnection.createAnswer(function(sessionDescription) {
//Set local description
peerConnection.setLocalDescription(sessionDescription);
//The local desc will be the answer sent back to offerer
signalingChannel.emit('answer', JSON.stringify(sessionDescription));
console.log("Answer sent");
});
});
}
function gotRemoteStream(event){
video2.src = window.webkitURL.createObjectURL(event.stream);
}
Here is a sequence of events I have working today (Feb 2014) in Chrome. This is for a simplified case where peer 1 will stream video to peer 2.
Set up some way for the peers to exchange messages. (The variance in how people accomplish this is what makes different WebRTC code samples so incommensurable, sadly. But mentally, and in your code organization, try to separate this logic out from the rest.)
On each side, set up message handlers for the important signalling messages. You can set them up and leave them up. There are 3 core messages to handle & send:
an ice candidate sent from the other side ==> call addIceCandidate with it
an offer message ==> SetRemoteDescription with it, then make an answer & send it
an answer message ===> SetRemoteDescription with it
On each side, create a new peerconnection object and attach event handlers to it for important events: onicecandidate, onremovestream, onaddstream, etc.
ice candidate ===> send it to other side
stream added ===> attach it to a video element so you can see it
When both peers are present and all the handlers are in place, peer 1 gets a trigger message of some kind to start video capture (using the getUserMedia call)
Once getUserMedia succeeds, we have a stream. Call addStream on the peer 1's peer connection object.
Then -- and only then -- peer 1 makes an offer
Due to the handlers we set up in step 2, peer 2 gets this and sends an answer
Concurrently with this (and somewhat obscurely), the peer connection object starts producing ice candidates. They get sent back and forth between the two peers and handled (steps 2 & 3 above)
Streaming starts by itself, opaquely, as a result of 2 conditions:
offer/answer exchange
ice candidates received, exchanged, and added
When I want to change the stream, I go back to step 3 and set up a new peer connection object and do the whole offer/answer again.
Why do you wait for ICE to complete before creating an answer? what about doing them simultaneously? That might help, as it is just meant to work simultaneously. If you can post your logs after this when it would still not work we can try debugging it even further. If you want to see an audio-only example of this (it sends both music-audio and microphone-audio) check here, and the github source. Server made with node.js and ws plugin. The audio connection works with webRTC.
I am attempting to listen to a particular event type regardless of the channel it was triggered in. My understanding of the docs (http://pusher.com/docs/client_api_guide/client_events#bind-events/lang=js) was that I can do so by calling the bind method on the pusher instance rather than on a channel instance. Here is my code:
var pusher = new Pusher('MYSECRETAPPKEY', {'encrypted':true}); // Replace with your app key
var eventName = 'new-comment';
var callback = function(data) {
// add comment into page
console.log(data);
};
pusher.bind(eventName, callback);
I then used the Event Creator tool in my account portal to generate an event. I used a random channel name, set the Event to "new-comment" and just put in some random piece of text into the Event Data. But, I am getting nothing appearing in my Console.
I am using https://d3dy5gmtp8yhk7.cloudfront.net/2.1/pusher.min.js, and performing this test in the latest Chrome.
What am I missing?
Thanks!
Shaheeb R.
Pusher will only send events to the client if that client has subscribed to the channel. So, the first thing you need to do is subscribe the channel. Binding to the event on the client:
pusher.bind('event_name', function( data ) {
// handle update
} );
This is also known as "global event binding".
I've tested this using this code and it does work:
http://jsbin.com/AROvEDO/1/edit
For completeness, here's the code:
var pusher = new Pusher('APP_KEY');
var channel = pusher.subscribe('test_channel');
pusher.bind('my_event', function(data) {
alert(data.message);
});