nginx proxy to remote node.js express app in subdirectory - node.js

Question

I am completely stuck with a situation where I want to have several node applications on one server. I get this working fine by having the applications running on different ports. I can access the applications by putting in the ip address with port.
I would like to proxy the applications from my nginx server by using different sub-directories like so:
my.domain
location /app1 {
proxy_pass http://10.131.6.181:3001;
}
location /app2 {
proxy_pass http://10.131.6.181:3002;
}
Doing this I had to move the all the express routes to /app1 for application1. This works but now I am stuck with the static files.
I can now access the application with http://10.131.6.181:3001/app1 which is great, but via http://my.domain/app1 the static files are not loaded.
The static files can be accessed directly http://10.131.6.181:3001/css but not via the proxy http://my.domain/css
Ideally I would like to have the applications on different ports without the sub-directory in the express routes but only sub-directories in the proxy. I tried to put my head through the wall for the last 5 hours but didn't achieve anything.
Now I would happy if can at least get the static files via the nginx proxy.

Answer 1

An updated answer for anyone who needs:
instead of
location /app1 {
proxy_pass http://10.131.6.181:3001/app1;
}
use
location /app1/ {
proxy_pass http://10.131.6.181:3001/;
}
or if on local
location /app1/ {
proxy_pass http://localhost:3000/;
}
This is the correct way and this way you will not need to modify express. Express will receive only the part after /app1/

Answer 2

I finally worked it out after a google surge.
I added the directories to the nginx proxy_pass
my.domain
location /app1 {
proxy_pass http://10.131.6.181:3001/app1;
}
location /app2 {
proxy_pass http://10.131.6.181:3002/app2;
}
And I had to change the express applications to use the subdirectory
app.use('/app1', express.static(path.join(__dirname, 'public')));
app.use('/app1'', require('./routes'));
In the router I had to prefix all the redirects.
router.get('/logout', function (req, res) {
req.logout();
res.redirect('/app1/login');
});
The static files are called like so from html
<link rel="stylesheet" href="/app1/css/style.css"/>
A bit of a pain to change all the redirects and static url. I am sure there is a smarter way by setting a global variable in my node-express app. If anybody knows an easier way please post...