Node.js does not run in a browser, therefore you will not have a document object available. Actually, you will not even have a DOM tree at all. If you are a bit confused at this point, I encourage you to read more about it before going further.
There are a few methods you can choose from to do what you want.
Method 1: Serving the file directly via HTTP
Because you wrote about opening the file in the browser, why don't you use a framework that will serve the file directly as an HTTP service, instead of having a two-step process? This way, your code will be more dynamic and easily maintainable (not mentioning your HTML always up-to-date).
There are plenty frameworks out there for that :
The most basic way you could do what you want is this :
var http = require('http');
http.createServer(function (req, res) {
var html = buildHtml(req);
res.writeHead(200, {
'Content-Type': 'text/html',
'Content-Length': html.length,
'Expires': new Date().toUTCString()
});
res.end(html);
}).listen(8080);
function buildHtml(req) {
var header = '';
var body = '';
// concatenate header string
// concatenate body string
return '<!DOCTYPE html>'
+ '<html><head>' + header + '</head><body>' + body + '</body></html>';
};
And access this HTML with http://localhost:8080 from your browser.
(Edit: you could also serve them with a small HTTP server.)
Method 2: Generating the file only
If what you are trying to do is simply generating some HTML files, then go simple. To perform IO access on the file system, Node has an API for that, documented here.
var fs = require('fs');
var fileName = 'path/to/file';
var stream = fs.createWriteStream(fileName);
stream.once('open', function(fd) {
var html = buildHtml();
stream.end(html);
});
Note: The buildHtml function is exactly the same as in Method 1.
Method 3: Dumping the file directly into stdout
This is the most basic Node.js implementation and requires the invoking application to handle the output itself. To output something in Node (ie. to stdout), the best way is to use console.log(message) where message is any string, or object, etc.
var html = buildHtml();
console.log(html);
Note: The buildHtml function is exactly the same as in Method 1 (again)
If your script is called html-generator.js (for example), in Linux/Unix based system, simply do
$ node html-generator.js > path/to/file
Conclusion
Because Node is a modular system, you can even put the buildHtml function inside it's own module and simply write adapters to handle the HTML however you like. Something like
var htmlBuilder = require('path/to/html-builder-module');
var html = htmlBuilder(options);
...
You have to think "server-side" and not "client-side" when writing JavaScript for Node.js; you are not in a browser and/or limited to a sandbox, other than the V8 engine.
Extra reading, learn about npm. Hope this helps.
