I having some doubts that:-
what is need to use the socket.io client we can use only the socket.io server to stop refreshing the app.
what is different between the socket.io client and socket.io server.
check this link
socket-io.client is the code for the client-side implementation of socket.io. That code may be used either by a browser client or by a server process that is initiating a socket.io connection to some other server (thus playing the client-side role in a socket.io connection).
A server that is not initiating socket.io connections to other servers would not use this code. This has been made a little more confusing that it probably should be because when using socket.io, it appears that both client and server are using the same socket.io.js file (because they both refer to a file with the same name), but is not actually the case. The server is using a different file than the client.
From the Github page for socket-io.client:
A standalone build of socket.io-client is exposed automatically by the socket.io server as /socket.io/socket.io.js. Alternatively you can serve the file socket.io.js found at the root of this repository.
Keep in mind that there are unique features that belong to client and server so it should not be a surprise that they use some different code. Though they share code for parsing the protocol and things like that, the server has the ability to run a server or hook into an existing web server and it has methods like .join() and .leave() and data structures that keep track of all the connected sockets and is expected to live in the node.js environment. The client has the ability to initiate a connection (send the right http request), do polling if webSockets are not supported, build on a native webSocket implementation if present, etc....
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I'd like to make a app with React-Native that's accept connections from another devices (Desktops or mobiles) through raw tcp sockets (like node's Net API) or WebSockets (like Socket.io). The point is that, socket server must be running on the React-Native's App.
I already tried Socket.io and react-native-tcp, it works when i make the server run on a nodeJS's application and the client on RN's app, but not the reverse.
When i try to import Socket.io and make it listen on a port, a error is raisen, because RN don't have node's http module. Just Socket.io/clients works.
I think that i'm doing something wrong, but is really possible to do that? and what is the best way?
Obs: I'm really new in RN's world.
No, we can't create a server although if we create a server we can't connect any other external applications to the server.
So create a server and deploy it in any could service then use it in your react-native app.
I try to make a client-server app with socket.io.
Socket.io server seems work but the client cannot connect to it. The error i get is about the '/socket.io/socket.io.js' like what it is unable to load it.
So here are my questions
is it mandatory to have server and client in the same folder as we can see in the official demo ?
can we make a nodejs socket.io server without express ?
Depending on how your project is setup, you need to create 2 server files, 1 for the app, and one for the websockets, and every time a user opens the app it should open(and be told where to try and open the connection) a connection to the websockets server. On my websockets apps I have the app running on localhost:3000, and websockets server on localhost:3001 (and tell the app to look for a server on 3001), so really you don't need to have the server files in the same folder, they can be in 2 opposite ends of your computer, as long as the app points to the server, then your fine, once a connection has been opened, the websocket server will see the client, and it should work! Let me know if that make sense.
No, you can download socket.io front-end lib from another sources, for example cdn. Be sure you installed the right version.
Yes, you can make it without express. Express is just another option for creating an socket.io server.
For example, currently in my project that is written in another back-end node framework i'm using the code below to establish the socket.io server.
const io = require("socket.io")(2337);
io.on("connection", socket =>
// some code
)
I fixed the problem of websocket communication between my server and my client.
After inspected my html client file, i saw on the console this error message 'ReferenceError: io is not defined'.
I google that error and i found this.
I am wondering if someone has used the socket.io-client library for communicating between servers instead of communicating between browsers to server.
Is this kosher?
Is the behavior of the library pretty much the same when the client library is running on a server vs running in the browser?
Can the socket.io-server library initialize connections with clients, or do socket.io-clients need to initialize connections?
Is this kosher?
Yes, that is exactly what the socket.io-client is designed for. It works great for communicating between two servers.
Is the behavior of the library pretty much the same when the client
library is running on a server vs running in the browser?
Yes, the behavior is identical. The only difference under the covers is that the browser implementation is built on top of the browser's webSocket support whereas the server-side client uses the socket.io webSocket implementation.
Can the socket.io-server library initialize connections with clients,
or do socket.io-clients need to initialize connections?
Only socket.io servers are "listening" for incoming connections. Somebody has to connect TO the socket.io server. You can't connect TO a socket.io client. A client must connect to a server. So, a socket.io client (which can be either in a browser or on a server) must be the one that creates the connection. Once connected, data can be sent either way on that connection.
Considering you are talking about the JavaScript version of the socket.io-client:
Yes, of course it is legitimate to use it server-side. it is just a "client" library, not only a "client-SIDE" library.
The behavior is the same, yes.
Clients need to initialize connections.
There is a server side usage example the Socket.io-client documentation
Other versions of the socket.io-client are also available in different languages (swift, java, CPP), that you can find on their Github page.
I basically want to know if its possible to use Socket.io using the server-side only with no client side? BUT I want to know if my server-side can instead connect with a different site that I cannot use Socket.io to connect to.
Use PhantomJS to load the third-party site and then inject your own javascript into the page to catch events and send those events back to your own server.
socket.io is a two-way connection. Client <--> Server. You must have a socket.io endpoint at both ends to even establish a connection in the first place. And, then once you establish the connection, you must have agreed upon messages that can be exchanged between the two ends for it to do anything useful.
It is not useful to have a server-side socket.io that doesn't actually connect to anything and nothing connects to it. It wouldn't be doing anything, just sitting there waiting for someone to connect to it.
It is possible to have two cooperating servers connect to one another with socket.io (one server just acts like a client in that case by initiating the connection to the other server). But, again both endpoints must participate in the connection for the connection to even be established and certainly for it to do anything useful.
If you just want to download the contents of a site for scraping purposes, then you would not use socket.io for that. You would just use the nodejs http module (or any of several other modules built on top of it). Your server would essentially pretend to be a browser. It would request a web page from any random web server using HTTP (not socket.io). That web server would return the web page via the normal HTTP request. Your receiving server can then do whatever it wants with that web page (scrape it, whatever).
I have been breaking my head on understanding what exactly is socket.io and its role in the whole persistent communication between client and server in general. Some fundamental questions that keep coming up in my mind are :
Are node.js and socket.io server different ways of doing the same thing ? Like lighthttpd and apache ?
Why should I use socket.io server if I have node.js ?
Can I use socket.io client with another server side programming language like PHP ?
Are there alternatives to using socket.io client ?
Is socket.io client just another javascript library for websocket communication ?
Thanks :)
The Socket.IO server accepts connections from Socket.IO clients. This is not any different than any other server (such as a web server like Apache) accepting a connection from a client (such as a web browser like Internet Explorer).
Node.js is a platform built on top of the V8 JavaScript engine, which comes with a convenient library usually used for web and network applications. Socket.IO is a web-socket-like communication wrapper and RPC which enables servers and clients to communicate over a variety of transports (every thing from long-polling JSON to real Web Sockets). Generally, the Socket.IO server code runs in your JavaScript application running on top of Node.js, and the Socket.IO client runs in your JavaScript on a web browser. (Note that you can run the Socket.IO client in your Node.js application to, which I have used in the past as a quick RPC between multiple Node.js applications.)
There are Socket.IO clients available for many languages, and yes I believe there is one for PHP but I haven't used it personally.
If you want to communicate with a Socket.IO server, you must use a Socket.IO client. It is a protocol all on its own.
Are node.js and socket.io server different ways of doing the same thing ?
SocketIO is actually a I/O engine that permits realtime communication between client and server, unlike classic HTTP requests.
Why should I use socket.io server if I have node.js ?
Since both are differents, we can't compare.
Can I use socket.io client with another server side programming language like PHP ?
No, because socketIO server run in NodeJS environment.
Client first make a HTTP request, then socketIO send a static JS script to client.
This script establish the two-way communication.
But you can use socketIO server with different socketIO client implementation.
Are there alternatives to using socket.io client ?
Any socketIO client implementation can do the job since they connected to server.
But beware of asynchronous way of communication, like in Java or PHP.
Is socket.io client just another javascript library for websocket communication ?
Yes it is, but socketIO aims on reliability and easy to use, and also do best effort : It choose the best transport available for client.
Hope it helps !
Are node.js and socket.io server different ways of doing the same thing ? Like lighthttpd and apache ?
Socket.io is a framework/library for node.js
Why should I use socket.io server if I have node.js ?
It's a framework designed for two-way communication, use it if you want
Can I use socket.io client with another server side programming language like PHP ?
Technically yes. But then you would have to reimplement socket.io server in that other language to match it.
Are there alternatives to using socket.io client ?
Lots of, google for websocket/real time communication in [here put your language]
Is socket.io client just another javascript library for websocket communication ?
Socket.io client is a JavaScript library compatibile with socket.io server (which is JavaScript library as well, only on the server side, i.e. Node.js)