Nginx internal location ignores django completely and allows free access instead - django

Question

I want to have a private media folder on my django website, accessible only to logged in users, so I got to know that I should handle authentication part on the django side, and file serving on the nginx side. However following internal location config examples I find it impossible to make it work. Nginx ignores django completely (only for the internal location case). Even if I don't have the url allowed in my urls.py and I have it listed as internal location in nginx, it will still be freely accessible to everybody.
I am posting my nginx configuration in hope that someone can find a mistake in it.
My expectation is that everything in /internal/ folder will not be accessible to anonymous users and it will only be accessible by the django application through X-Accel-Redirect header. Right now if I go to /internal/test.png in an incognito window it will show me the picture.
I am not posting my django code for now, since it is ignored anyway by nginx, so it must be the nginx config problem.
server {
server_name XXX.XX.XX.XXX example.com www.example.com;
location = /favicon.ico {
access_log off;
log_not_found off;
alias /home/user/myproject/static/favicon4.ico;
}
location /static/ {
root /home/user/myproject;
}
location /media/ {
root /home/user/myproject;
}
location / {
include proxy_params;
proxy_pass http://unix:/run/gunicorn.sock;
}
location /internal/ {
internal;
root /home/user/myproject;
}
root /home/user/myproject;
location ~* \.(jpg|jpeg|png|webp|ico|gif)$ {
expires 30d;
}
location ~* \.(css|js|pdf)$ {
expires 1d;
}
client_max_body_size 10M;
# below in this server block is only my Certbot stuff
}
P.S. I swapped identifiable data to X characters and basic names.

Answer 1

I had 2 more problems in this config and I will show everything I did to make it work. The original problem why nginx was ignoring django was in how nginx chooses which location block to use, as suggested by Richard Smith.
From nginx.org we can read:
To find location matching a given request, nginx first checks locations defined using the prefix strings (prefix locations). Among them, the location with the longest matching prefix is selected and remembered. Then regular expressions are checked, in the order of their appearance in the configuration file. The search of regular expressions terminates on the first match, and the corresponding configuration is used. If no match with a regular expression is found then the configuration of the prefix location remembered earlier is used.
And also:
If the longest matching prefix location has the “^~” modifier then regular expressions are not checked.
So regular expressions, if available, will be chosen first. ^~ modifier before prefix makes it chosen instead of regular expressions.
I changed location /internal/ { line to location ^~ /internal/ { and then I got 404 errors every time and no matter how I tried to access the files, but at least I knew nginx was going to this location.
The 2nd mistake was thinking that I can get away with using the same url as the folder name, or in other words, that I can put in my urls.py
path('internal/<path>', views.internal_media, name='internal_media')
together with
location ^~ /internal/ {
internal;
root /home/user/myproject;
}
in my nginx config.
I can't. The url must be different, because otherwise the url doesn't lead to django urls.py - it still leads to /internal/ location through nginx (again, due to how nginx chooses locations).
I changed my urls.py line to point to private url instead:
path('private/<path>', views.internal_media, name='internal_media')
and in the views.py file I redirect to /internal/:
def internal_media(request, path):
if request.user.groups.filter(name='team-special').exists():
response = HttpResponse()
response['X-Accel-Redirect'] = '/internal/' + path
del response['Content-Type'] # without this your images will open as text
return response
else:
raise PermissionDenied()
Aaaand this still didn't work. 404 errors every time. The 3rd mistake was forgetting about the combo of those two:
location / {
include proxy_params;
proxy_pass http://unix:/run/gunicorn.sock;
}
location ~* \.(jpg|jpeg|png|webp|ico|gif)$ {
expires 30d;
}
Now if I went to the url /private/test.jpg nginx didn't let me go to django, because location / is lower in priority than regular expressions, so location ~* took precedence and I never got to django. I noticed it by accident after a lot of time being frustrated, when I put the url incorrectly in incognito mode. When I went to /private/test.jp now I got a 403 forbidden error instead of 404.
It started working immediately when I commented out this.
location ~* \.(jpg|jpeg|png|webp|ico|gif)$ {
expires 30d;
}
location ~* \.(css|js|pdf)$ {
expires 1d;
}
So now internal files worked nicely, but I didn't have caching...
To fix that, I modified my /static/ and /media/ locations, but maybe I won't go into that here, since it is a different topic. I'll just post my full nginx config that works :)
Well, what you might want to also know is that:
~* tells nginx that we are writing a regular expression that is case insensitive
~ would tell nginx that we were writing a regular expression that is case sensitive
server {
server_name XXX.XX.XX.XXX example.com www.example.com;
location = /favicon.ico {
access_log off;
log_not_found off;
alias /home/user/myproject/static/favicon4.ico;
expires 30d;
}
location /static/ {
root /home/user/myproject;
expires 30d;
}
location /media/ {
root /home/user/myproject;
expires 30d;
}
location ~* \/(static|media)\/\S*\.(css|js|pdf) {
root /home/user/myproject;
expires 1d;
}
location ^~ /internal/ {
root /home/user/myproject;
internal;
expires 1d;
}
location / {
include proxy_params;
proxy_pass http://unix:/run/gunicorn.sock;
}
client_max_body_size 10M;
# certbot stuff
}