node.js - communicate with TCP server (data == JSON)

I'm new to node.js, dived into it during the last weekend and had fun with various examples and small tutorials. Now I'd like to start a little project for my local area network and have a few questions to get myself into the right direction.

Setup:

I've got a server service running on my lan. It's possible to communicate with that service via TCP and/or HTTP (it's possible to enable or disable TCP or HTTP or both of them) on a specific port and sends and re开发者_Go百科ceives data via JSON on a request. What I basically want to do is to create a webinterface based on node.js for that service, to receive and send JSON data with a webbrowser from and to that service.

Problem:

I already do know how to setup an http server based on node.js. But right now I'm stuck in finding an idea how to create a client based on node.js which stands between the service and the webbrowser client to pass through data from client to server and vise versa. Something like a router or proxy.

Here is a basic scheme based on the client's (webbrowser) point of view:

Send: Webbrowser requests -> node.js routes -> service receives

Receive: Webbrowser receives <- node.js routes <- service responds

Questions:

- Go for TCP or HTTP? (maybe disabling the HTTP Server would spare some ressources) - maybe already answered by this post

- Are there any node.js packages that would fit my needs?

- Go for a framework (expressions?) or would plain node.js be just enough?

- Any hints appreciated :)

edit:

- Is it possible to bind a network device like eth0 inside node.js instead of defining the ip address?

Thanks for your help && best regards

cefra

There's no reason why you can't have a REST HTTP service.

Use something like express to handle routing.

If I understand your problem correctly then you have a webservice written in "foobar" on a TCP port somewhere you can connect to with node.

So if your using express you would write something like

app.get("/resources/", function(req, res) {
    var socket = new net.Socket();
    socket.connect(port, host, function() {
        socket.on("data", function(json) {
            res.contentType("json");
            res.send(json);
            socket.end();
        });
        socket.write(...);
    });
});

So basically you've written a http middleman that contacts your service over TCP then writes the data down the response of your HTTP request.