coffeerings's posterous

Using Node JS and Couch DB Stack for Web Dev

With all the recent hype of http://nodejs.org/ I thought it'd be worth a go. Very crude example but does what it says on the tin, uses Node JS to create a server and when requested gets data from Couch DB and displays it in a web page.

You can download and install Node from http://nodejs.org/#download
I used the OSX Couch DB install from http://janl.github.com/couchdbx/ but see http://couchdb.apache.org/ for other platforms.

I've setup a DB on called monkey with 2 records, it can be reached at http://127.0.0.1:5984/monkey/_all_docs. />
You'll need 2 files for this demo - a html template, template.html (used for the output) and the js file (all the clever bits).
Simply copy/paste the following code to a .js file next to template.html and executing $ node my-file.js. Go to your browser and type in http://127.0.0.1:8001/ to see the page.

var sys = require("sys"),
    http = require("http");
    posix = require("posix");

http.createServer(function (req, res) {
    res.sendHeader(200, {'Content-Type': 'text/html'});
     
    var couch = http.createClient(5984, "localhost");
    var request = couch.get("/monkey/_all_docs", {"host": "localhost"});
    var template = posix.cat('template.html').wait();
     
    request.finish(function (response) {
      response.setBodyEncoding("utf8");

        var response_body_str = "";
        if(response.statusCode == 200){
            response.addListener("body", function (chunk) {
                 response_body_str += chunk;
          });

            response.addListener("complete", function() {
                response_body = JSON.parse(response_body_str);
                template = template.replace("__total_records__",response_body.total_rows);
                 template = template.replace("__json__",JSON.stringify(response_body));
                res.sendBody(template);
                res.finish();
            });
        }
        else sys.puts('invalid responce');
     });
}).listen(8001);

sys.puts('Server running at http://127.0.0.1:8001/');

The html template:

<?xml version="1.0" encoding="UTF-8"?>
 <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN"
    "http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd">

<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en">
     <head>
        <title>Node JS + Couch DB Demo</title>
        <style>
            body{font-family:arial; font-size:1em; line-height:1.2em;}
            h1{font-size:1.3em;}
        </style>
     </head>
    <body>
        <h1>Node JS + Couch DB Demo</h1>
        <p><strong>Total Records: __total_records__</strong><p>
        <pre>
            __json__
         </pre>
    </body>
</html>

This was a rather quick hack to see what Node was capable off so I'll be following this up with something more useful (and less hacky) soon.