Question

I am building a small app primarily with socket io, however with a few things from expressjs.

One function of the socket io piece is to send an email when a certain event occurs. I’ve got this working fine with node_mailer.

The problem I’m running into is that I want to use the express view engine to render the emails from template files. The render method seems to be explicitly attached to the res object prototype.

What I’ve done feels pretty dirty:

// setup express server
var render;
app.get('/', function (req, res) {
    if (typeof render == 'undefined') render = res.render;
    res.end('Welcome to app');
});

// socket io code
socket.on('event', function (data) {
    var email_content;
    render('template', {}, function (err, result) { email_content = result; });
});

Is there a better way to gain access to expressjs’s components outside the context of an http request, or even a better way to approach this problem? I tried rigging up a call to the exported express.view.compile function but that both didn’t work and seemed like a high hoo

Answer 1

Here is where the information you seek comes from:

https://github.com/Ravelsoft/node-jinjs/wiki

With templates as modules
To have node load your templates as if they were modules, you first have to register your module extension :

require("jinjs").registerExtension(".tpl");

If you want your file to be transformed prior to being submitted to jinjs, you can pass a callback ;

var pwilang = require("pwilang");
require("jinjs").registerExtension(".pwx", function (txt) { 
    return pwilang.parse(txt); 
});

You can now write this to user Jin:

var my_template = require("./mytemplate");
var context = { foo: "foo", bar: "bar" };
var result = my_template.render(context);

Because you are sticking Jin into express (as opposed to making express work with Jin) this is your best option. The res variable is only available in the route callback.