I know there are a bunch of questions on this already, but none have answered it for me, and plus mine is slightly different.
I'm starting the socket.io server in node using this:
var io = require('socket.io').listen(8000);
My terminal says everything is ok:
info - socket.io started
Now I am trying to load the .js file in my clientside browser using this url:
http://<hostname>:8000/socket.io/socket.io.js
I dont get a 404, it just hangs forever. I've also used a network utility to ping port 8000, and it seems to be open fine.
I installed node and socket.io just yesterday, so they should be the latest versions. Can anyone shed any light on this? Thanks!
Turns out the reason I could never request the .js file was because my company network blocks all ports except the usual ones (80, 21, etc), so `I would never be able to communicate with port 8000.
Use express.js. Place the socket.io file in public/javascripts folder and add this line to your html
<script src="/javascripts/socket.io.js"></script>
I think this is the best way. When you're writing http://<hostname>:8000/socket.io/socket.io.js
node tries to find a folder named socket.io in your project's public folder. And the file socket.io.js in it.
If you don't want to use express.js you should catch the request and try to load a file if no routes were found for your request (what actually express does) because node doesn't know what to do for requests which don't match any routes in your server.
And I recommend to use the socket.io.min.js file (it's smaller and it's in folder node_modules\socket.io\node_modules\socket.io-client\dist)
You have to start an http/https server to access it via http/https. Simply starting an socket.io server won't do. Do the following:
var http = require('http');
var app = http.createServer(),
io = require('socket.io').listen(app);
app.listen(7000, "0.0.0.0");
Then I can access the file http://localhost:7000/socket.io/socket.io.js
sockets.io uses websocket protocol (ws://). See the wikipedia page.
You need to get at least 3 pieces working together.
Serve some HTML (/index.html will do just fine) so there's a web page. This file should contain the socket.io client <script> tag. For this you need the http server portion of the starter examples. You are missing this and that's why browsing to your server just hangs.
Serve the socket.io client. Socket.io will do this for you automatically when you pass in your http server function to it. You don't need full express as this can be done with just node's http module as per the first example on the socket.io docs.
Some javascript to actually do something with the socket. This can be the content of a <script> tag in index.html or a separate file. If it's a separate file, you need to set up your http server to actually serve it.
Related
I don't really have experience with backend and how things work together. I have created a simple live message sending app with node.js and socket.io. When I host a static web server on my machine (http-server which runs on local port using node.js) my app works perfectly fine but when I upload it on my host or github pages just for test, the backend doesn't seem to work. I uploaded all my files with an FTP program and the frontend loads fine but the backend doesn't. Do I have to know something like Django or ASP.NET to make these work on my host?
EDIT: One more thing, first line in my server.js is const io = require('socket.io')(3000)and in my script.js - const socket = io('http://localhost:3000')where 3000 and localhost:3000 stands for local host in my machine. What do i need to put instead of these?
You probably need to install and setup Node.js on your server, contact yout hosting provider for node installation if the option isn't available in yout cPanel.
I have a node server with several node projects. I use nginx to get them all responding on port 80. Now, this works for the initial http request. For the websockets, I need to use the direct server port. To keep everything alive while developing I would like to try this, projects will have a dev and live version. Once de dev is stable, I will copy it to the live folder. The live folder is runned by a systemctl script where I define a difrent port to the live version so I can dev without taking the live down. The problem I encounter now is, how can I get the running server port in my client side Javascript so that the dev page connect to the dev port and visa versa?
currently I'm only using express, socket.io and mysql. I have no further npm packages installed. I searched allot but there is not to mush I can find. I found how to connect the socket to the page url but I cannot use that because that URL will always be on port 80. Further I found allot of huge packages that has no use for me since the original page is just static, the dynamics all run over websockets.
Is there any way to parse the port number in the clients .js file like I could do fairly easy in php? And if so, what would be the most efficient way. I could let javascript check if the page uses the live or dev URL but I would prefer not to hardcode my dev URL into JS where it is for everyone to see.
run a third node.js socket.io server program, all your clients connect to this server first.
In this simple node.js program, determine the type of clients by any means. e.g. different user id for dev/production users
send the server url and port to your client according to its type (dev or production)
you may also use this technique to separate your users to different production servers.
I have node js server that has a server which listens 8000 port and a socket.io connection working on that server. This socket connection creates a communication with a ReactJS app which is not a point of this question. So I have 2 project folders
1. project-server
2. project-web-react
Project server only answers socketio request and does not render a HTML or something else. It only works on terminal. I want to ask whether is it useful to encapsulate my project-server with Nginx? So the requests are handled by Nginx ? Or is it out of the Nginx's purpose?
I would never have an application server run directly connected through internet since there are always a bunch of unknowns with them (scaling, standard compliance etc), so I would recommend you to run a proxy like nginx in front of your app. This also makes it easy to add certificates and do load balancing / caching. It just adds flexibility and some security.
Last 2 days I spent more time and read 50+ articles and video to understand node.js and after installation now I can see the result in browser by http//:localhost:3000/ But I have confused in many case that I describe below.
I do all of my work in my share hosting server where I my keep my web site: www.myweb.com
In every article about node.js, they are teaching how to get a result by below code in a browser by http//:localhost:3000/ in local pc server.
test.js
var http = require('http');
http.createServer(function (request, response) {
response.writeHead(200, {'Content-Type': 'text/plain'});
response.end('Hello World\n');
}).listen(3000);
console.log('Server running at http://localhost:3000/');
But My Question:
If I use http//:www.myweb.com/test.js` in my browser, What will be the above code?
In case of local pc we write on npm node test.js, But In case of hosting server when any clint open the page like http//:www.myweb.com/test.js How to work it?
In case of php we used include ("head.php") to got something from that page But In this case How to make a call on node.js.
Well, what you need to do is understand how http web servers works.
Usually, on your remote machine (your server), you have an instance of a web server (ex : apache) running, which is listening to port 80 (standard port for http requests). It will handle every request made on that port, and manage routing to use the correct php/html file.
Then, it will run the php code server-side, to render an html file and serve it to the server. So the client will not see the php code at all.
Let's talk about Node.js. Node is an application that runs javascript code server-side, and can run an http server with using some modules. But the javascript code will never be shown to your client, he will only get the http response you send him (typically, the html page).
So now, with node.js, you need to do the same as the apache server did, by creating the http server. First, what you have to know is that not that many website host are offering node.js, or even console access. They usually serve the php/html files you put in the configured folder, and that's basically it. What you need is either a virtual machine, or a server on which you can install node.js and run it, or use a node.js hosting service, like heroku or nodejitsu to host your node.js http server.
So, to create the node.js http server, you need to create an http server (as you did in your code), and make it listen to port 80. Now, every http request send to your server will be handled by your node.js instance. Then, you can do anything you want with that request.
I hope I haven't been to messy.
You need to install NodeJS on the server. If this is shared hosting where you cannot install additional software then you will be unable to use NodeJS. In that case contact support of your web hosting company and inquire about NodeJS support.
On the other hand, if you do have root user or super user rights on a system, you can install NodeJS. For example for on CentOS/RHEL systems you can install using yum with the following commands.
sudo yum install epel-release
sudo yum install npm
For some of the other distributions of Linux: http://ask.xmodulo.com/install-node-js-linux.html
To access Node applications from your PC to the server, you also need to open a port in the server firewall that your Node aplication uses.
From what I have read so far in this blog http://nowjs.com/ I need to install nodejs in the server machine for it to work. But, I am using a shared server and don't really have any authority to put something into the server machine.
Putting it into the container(tomcat) is however another thing which I mostly do.
Generally speaking, when we say server we mean tomcat or websphere or jboss.
But with nodejs if I am not wrong server means the real machine on which tomcat etc. runs.
So is there any way I can run the nodejs server inside tomcat server or am I thinking about it the wrong way ?
Yes, you are thinking of it it the wrong way. The key feature of Nodejs is that it contains, amongst other things, a rather natty embedded HTTP server. Think Jetty. However it might be possible now or in the future to run JavaScript in tomcat.
I recommend going to http://nodejs.org/ and watching the video, it will surely clear the matter up for you.
Meanwhile I would recommend getting hosting which includes SSH access, and preferably root access. Root access will make installing node a whole load easier and allow you to run it on a commonly used port (avoid running node as root, use port mapping) . But you don't need a seperate web server to get started, you can install Node.js on windows, mac and linux.