I am building a SOA with deepstream and I want to use a deepstream client server to perform API-KEY based look ups that the user should not know. How do I actually set up an RPC client provider? I have looked in the deepstream docs and on google, but there is not a full code example on how to do this. I have created a file like below and run it with node. The output I get is below it:
var deepstream = require('deepstream.io-client-js')
const client = deepstream('localhost:6020').login()
console.log('Starting up')
client.on('error', (error,event,topic) => {
console.log(error, event, topic);
})
client.on('connectionStateChanged', connectionState => {
console.log(connectionState);
})
client.login({username: 'USER', password: 'PASSWORD'}, (success, data) => {
if (success) {
client.rpc.provide('the-rpc', function( data, response ){
response.send(data);
});
} else {
console.log(data);
}
})
--
Starting up
AWAITING_CONNECTION
As you can see it runs the code, but does not actually connect to the deepstream server. I already have the deepstream server running, and a browser client that connects to it, so the config is correct. Please help!
I think your issue is based on the fact your trying to connect node via the webport. Try using port 6021 instead for tcp ( used by the node client ).
const client = deepstream('localhost:6021').login()
You should also only call .login() once, so the line would be:
const client = deepstream('localhost:6021')
We are working on a 2.0 release coming out very soon which will remove tcp entirely and only require a single port to make life easier in terms of deployment and performance.
Related
I googled a lot but still have no clear solution to my issue.
Connecting to MongoDB, usually you establish a connection and after the job is done you close it.
Since next.js (and probably node.js) is single threaded. Sometimes it happens that there are two requests processed async while one request established the connection to the database, the otherone is closing the exact same connection. So the first request runs into an Topology closed exception. I have the feeling that the mongodb driver client is shared.
Is there something I did not understood correct in this?
try {
await client.connect()
const database = client.db("test")
const collection = database.collection("test")
const newDataset = await collection.insertOne({})
return newDataset.insertedId.toString()
} finally {
await client.close();
}
As in the comments stated, ive seen a lot of examples & questions here on stackoverflow where in each received request (example below) a database connection is established. This has no benefits and is "bad" because it just takes time and makes no sense. E.g:
app.get("/", (req, res) => {
MongoClient.connect("...", (err, client) => {
// do what ever you want here
client.close();
});
});
If you application needs a database connection, establish the connection "in the startup phase" and keep the connection open. There is no reason to open and close the database connection for each request.
const mongodb = require("monogdb");
const express = require("express");
const app = express();
// some custom init stuff
// e.g. require your route handler etc.
mongodb.MongoClient("...", (err, client) => {
// do what ever you want with the db connection now
// e.g. monkey patch it, so you can use it in other files
// (There are better ways to handle that)
mongodb.client = client;
// or the better way
// pass it as function parameter
require("./routes")(app, client);
app.listen(8080, () => {
console.log("http server listening");
});
});
As you can see in the code above, we first create a database connection and then do other stuff. This has some advantages:
If your credentials are invalid, your application is not externeal reachable because the http server is not started
You have a single connection for all requests
Database queries are potential faster because you dont have to wait to establish first a db connection
NOTE: the code above was "inline coded" here and is not tested.
But i think its illustrated the concept behind my statement.
I am working on writing server-side code in node.js for a swift based iOS application. Currently, the code works when running it on one EC2 instance, but I am working on setting up a network load balancer so that it can more appropriately scale with incoming user traffic. I decided that the easiest way to achieve this is to use the redis adapter. So now, my server.js file includes:
const app = new Koa();
const server = http.createServer(app.callback));
const io = require('socket.io')(server);
const redisAdapter = require('socket.io-redis');
io.adapter({ host: 'my-elasticache-redis-endpoint', port: 6379 })
Based on the documentation, this seemed like the only step that was necessary from a code standpoint to get redis actually working in the project, but I may be missing something. From an architecture perspective, I enabled sticky sessions on the target group and set up two servers, both running this code. In addition, if I print out the socket io information, I can see that it has adequately connected to the redis endpoint.
The issue is as follows. Lets say I have two people, Person A and Person B, each connected to different servers. The application is supposed to function like so:
Person A adds person B to a socket room. Then the server emits an event to everyone in that room saying that person B has joined, so the front end can respond accordingly.
This is done through the following function:
protected async r_joinRoom(game: GameEntity, player: PlayerEntity): Promise<void> {
return new Promise((res, rej) => {
let socket: any;
socket = this._io.sockets.connected[player.socket_id];
if (!socket) {
socket = this._socket;
}
socket.join(`game/${game.id}`, (err: any) => {
if (err) {
return rej(new GameError(`Unable to join the room=${game.id}.\n${err}`));
}
res();
});
});
}
The premise here is that Person B is a player, and as a player, he has an associated socket id that the server is keeping track of. I believe the issue, however, is that socket = this._io.sockets.connected[player.socket_id]; Does not find the connected player, because he is technically connected to a different server. Printing out the socket shows it as null, and if I subsequently have that exact same function run on the server player B is connected to, he joins the room no problem. Therefore, when the emitted events takes place following 'adding' person B to the room, only person A's phone gets the event, and not B. So is this an issue with my Redis setup? Or is there a way to get all the connected clients to any of the servers running the node.js app?
I ended up answering my own question. When you add to the room, you have to do it directly from the adapter. From the documentation, that means I would switch socket.join... to
io.of('/').adapter.remoteJoin('<my-id>', 'room1', (err) => {
if (err) { /* unknown id */ }
// success
});
using that remoteJoin function worked off the bat
Am newbie in node.js and would like to grab all events types.
In this case i already did my homework.I found from far this one.
In link, Continuosly throwing below error.
Error :
TypeError: esl.createCallServer is not a function
I am expecting : If any call has been started and forward to the gateway.So on the realtime would like to get gateway name in node.js to check which gateway is using
Might be possible,I understand is not correct way but below also one more try to achieve this but that not giving me gateway information.
call_handler = require('seem');
const esl = require("esl");
const port = 4041;
const server = esl.server(call_handler).listen(port);
server.listen(port, function() {
console.log("Server listening for connection requests on socket localhost:"+port);
});
esl.client(call_handler).connect(4050);
server.on("connection", function(chunk) {
console.log("Connection has been established");
chunk.on("data", (data) => {
console.log("Channel Park info");
var data_string = data.toString();
var data_arr= data_string.replace(/\r\n/g, "\r").replace(/\n/g, "\r").split(/\r/);
var data_array= JSON.stringify( data_arr );
console.log(data_array);
chunk.end();
});
});
Node.js server have port is 4050.
From Freeswitch dialplan, I am executing below line
<action application="socket" data="127.0.0.1:4041 full"/>
Expected Output :
Whenever call is bridge on any gateway then after and before complete call am able to get bridge line from node.js
Also parameters which are added in dialplan as set/export that also must be get on node.js
Anyone like to share some hints for this problem ?
I have a Node.js script which is supposed to regularly access a SailsJS application via a socket connection. Client and server run on physically different machines on different networks. The SailsJS application is proxied behind nginx. That works in general. However, at random times, the connection is established but the first post request within the websocket connection never reaches its destination.
The code looks basically like this:
var socketIOClient = require('socket.io-client');
var sailsIOClient = require('sails.io.js');
var io = sailsIOClient(socketIOClient);
io.sails.url = 'https://foo.foo:443';
io.sails.rejectUnauthorized = false;
io.socket.on('connect', function() {
console.log("Connected!")
io.socket.post('/someroute', { someOptions: "foo" } ,
function(data) {
console.log(data);
});
});
io.socket.on('disconnect', function(){
console.log("Disconnected!");
});
io.socket.on('connect_error',function () {
console.log("connect_error!");
});
In case of a failure, simply nothing happens after console.log("Connected!"). Nothing appears in nginx's logs (in contrast to successful cases), the callback of io.socket.post never gets executed.
The most important question for me is: At which side is the problem? Client or server?
How can I debug this and narrow down the problem? Could it be a networking issue? Or something wrong the configuration, implementation or with the script itself?
I am choosing a XMPP server, and currently trying NodeXMPP.
I installed complete NodeXMPP (core,server,client,component,dependencies...).
What is striking me is that I have to do all the back-end stuff : making clients speak to each other etc. Other XMPP servers (tigase ejabberd ...) do this stuff from scratch.
My tiny instance :
I create a server and store clients in an array, then search for a client when an other try to speak :
var xmpp = require('../index')
var c2s = new xmpp.C2SServer({
port: 5222,
domain: 'localhost'
})
var clients = new Array();
c2s.on('connect', function(client) {
client.on('authenticate', function(opts, cb) {
console.log('AUTH' + opts.jid + ' -> ' +opts.password)
clients.push(client);
})
client.on('stanza', function(stanza) {
if (stanza.is('message') && (stanza.attrs.type !== 'error')) {
var interlocuteur = getClient(stanza.attrs.to)
if (interlocuteur)
interlocuteur.send(stanza)
}
})
client.on('disconnect', function() {
console.log('DISCONNECT')
})
client.on('online', function() {
console.log('ONLINE')
client.send(new xmpp.Message({ type: 'chat' }).c('body').t('Hello there, little client.'))
})
})
And my question : do I really need to code these basic operations by myself ?
If so, what is the point of Node-XMPP ? Maybe it's to use NodeJS over an other XMPP server like prosody ?
node-xmpp is "just" a library of components that allows you to build your own XMPP client, component or even server.
Being a library, it does not provide a complete solution for particular use case, but a set of building blocks allowing to build one.
If you are in the market of a complete, already made, boxed XMPP server solution, installing Prosody is a good bet. :^)