Nginx cache static files from different aplications - caching

Question

I use WordPress as a home page (mysite.com) and Django for the rest (mysite.com/pages). I have single nginx config file for both of them and its working fine. Moreover, they reside in a single server block.
Here are some parts of my configuration:
server {
...
root /var/www/wordpress;
...
location /static/ {
alias /home/username/Env/virtenv/mysite/static/;
}
}
With this both WordPress and Django static files are served.
Now I want to cache all static files for 7 days in the browser. If I put this in addition:
location ~* \.(jpg|jpeg|png|svg|gif|ico|css|js)$ {
expires 7d;
}
then the WordPress static files are properly cached, but Django's static files are not even served.
I know this is because the /static/ location is never reached and then Nginx searched Django's files in the root directive which is on server block level and which points to the WordPress location.
I can remove the cache location and add expires 7d; in the /static/ location. This will in opposite cache only the static files of Django.
But how can I make both static resources to be cached for a week?

Answer 1

Finally I was able to cache both static files - of Wordpress and Django.
For requests starting with /static/, I found a way to make Nginx use the /static/ location and not the general static files location, which has the purpose to only cache Wordpress static files.
Its so simple: just use the location modifier ^~.
As this wonderful article of DigitalOcean says:
The block modifier ^~ means that if this block is selected as the best non-regular expression match, regular expression matching will not take place.
Here is the working version of the two location blocks:
location ~* \.(?:jpg|jpeg|png|svg|gif|ico|css|js)$ {
# Cache Wordpress or any other public static files
# of those types for a week in the browser
expires 7d;
}
location ^~ /static/ {
alias /home/username/Env/virtenv/mysite/static/;
# Cache Django's static files for a week in the browser
expires 7d;
}
All requests with mysite.com/static/... will match the /static/ location and will not continue to any other regex location.
And for example requests as mysite.com/wp-content/themes/a-theme/style.css?ver=4.7.2
will match the regex location.