Access to mountpath variable from inside a template using express - node.js

Question

Is there a clean, recomended way to access the mountpath from inside a template, so an express app can be run both standalone and as a part of another app (by means of app.use), with the paths pointing to the correct destination either way?
Something like:
{{mountpath}}route/to/file
So in the case that the app is running standalone, mountpath will be /, and in case is running as a submodule, mountpath could be /foo/
Note: I'm using handlebars.

Answer 1

express.static middleware is responsible for serving the static assets of an Express application.
How it works:
Serve static content for the app from the "public" directory in the application directory
// GET /style.css etc
app.use(express.static(__dirname + '/public'));
Mount the middleware at "/static" to serve static content only when their request path is prefixed with "/static"
// GET /static/style.css etc.
app.use('/static', express.static(__dirname + '/public'));
Serve static files from multiple directories, but give precedence to "./public" over the others
app.use(express.static(__dirname + '/public'));
app.use(express.static(__dirname + '/files'));
app.use(express.static(__dirname + '/uploads'));
In your case you can use the second case i.e.; mounting files on path '/static', so whatever files are under the folder public can be accesses with src='/static/filename.xyz'
Create a folder name public with sub folders css, js, images
Or if you want your css to be mounted on path /css then you do :
app.use('/css',express.static(path.join(__dirname, 'module1/css')));
Now you can use all your css files in your entire application as :
<link href="css/style.css" rel="stylesheet">

Answer 2

There is an event that is fired after the module is mounted, so I can do:
app.locals.modulePath = "/";
app.on('mount', function (parent) {
app.locals.modulePath = app.mountpath;
});
The locals are directly accessible from inside all the views, so this will be accessible like {{modulePath}}

Answer 3

I had the same issue - needed to use mountpath from inside a template.
Solution that works for me is based on 2 facts
mountpath is available in request - req.baseUrl
response locals object gets exported to the template - res.locals
First, create a one-line middleware - this will apply to all routes inside the module/subapp
router.use(function (req, res, next) {
res.locals.baseUrl = req.baseUrl;
next();
});
Then inside the template use #{baseUrl}/some/route - note that this is jade syntax, but I suppose it works the same way with handlebars.