static file in node.js

    fs.readFile(this.files[uri], "binary", function(err, content) {
        if (err) {
            res.sendHeader(404, {
            });
        } else {
            res.sendHeader(200, {
                "Content-Type": mime_type,
                "Cache-Control": "public, max-age=300"
            });
            res.write(content, "binary");
        }
        res.end();
    });