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Running a "full-featured" REPL using a net.Server and net.Socket
var net = require('net')
var sock = net.connect(1337)
process.stdin.pipe(sock)
sock.pipe(process.stdout)
sock.on('connect', function () {
process.stdin.resume();
process.stdin.setRawMode(true)
})
sock.on('close', function done () {
process.stdin.setRawMode(false)
process.stdin.pause()
sock.removeListener('close', done)
})
process.stdin.on('end', function () {
sock.destroy()
console.log()
})
process.stdin.on('data', function (b) {
if (b.length === 1 && b[0] === 4) {
process.stdin.emit('end')
}
})
var repl = require('repl')
var net = require('net')
net.createServer(function (socket) {
var r = repl.start({
prompt: 'socket '+socket.remoteAddress+':'+socket.remotePort+'> '
, input: socket
, output: socket
, terminal: true
, useGlobal: false
})
r.on('exit', function () {
socket.end()
})
r.context.socket = socket
}).listen(1337)
@TooTallNate
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Author

@newleafdigital You need node v0.8.0 for this example.

@benbuckman
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Thanks

@benbuckman
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Is there any way in 0.6 to pipe stdout / console.log to a repl, so while I'm running commands, I can see the logs? It seems like it should be straightforward, but I can't get it to work.

@AlexeyKupershtokh
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    r.context.inspect = function(value) {
        r.outputStream.write('\n' + r.writer(value) + '\n');
        r.displayPrompt();
    };

This method is useful as callback to inspect values when console.log() is unavailable.
Example of usage:

socket 127.0.0.1:39022> setTimeout(function() {inspect(user);}, 1000);null;
null // immediate reaction
socket 127.0.0.1:39022> 
{ coins: 10 } // after the timeout
socket 127.0.0.1:39022>

Though please be careful: this code crashes the server if repl client disconnects before the timeout.

@qzaidi
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qzaidi commented Apr 21, 2013

Looks like this stopped working with 0.10.0, running the client results in the following error.

_stream_readable.js:683
throw new Error('Cannot switch to old mode now.');

@sandover
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I'm curious, too -- I'd like a remote REPL participant to be able to see the results of whatever they do, in their own REPL, instead of having that output "leak" back into the terminal where the program is running.

@jakwings
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jakwings commented Dec 3, 2013

@JigneshPansuriaDeveloper

var socket = require('engine.io-client');
console.log(socket.remoteAddress);

i am not getting remote addeess and it gives undefined

@JigneshPansuriaDeveloper

req.headers['x-forwarded-for'] it gives local ip address ...

i want remote ip address

@KrishnaAnanthi
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how to start the client and server in this application?

@KrishnaAnanthi
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i tried node repl-server.js it is giving me an error
module.js:538
throw err;
^

Error: Cannot find module 'C:\D Drive\Learning\repl-server.js'
at Function.Module._resolveFilename (module.js:536:15)
at Function.Module._load (module.js:466:25)
at Function.Module.runMain (module.js:676:10)
at startup (bootstrap_node.js:187:16)
at bootstrap_node.js:608:3

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