nginx sends header from different location directive - nginx

Question

I have the following nginx config, which basically has two locations which matches
a) routes including a dot (e.g. "/js/script.js") and
b) all other routes.
server {
listen 80;
server_name localhost;
root /app;
# files
# for all routes matching a dot, check for files and return 404 if not found
# e.g. /file.js returns a 404 if not found
location ~ \. {
add_header Cache-Control "public, max-age=2678400";
try_files $uri $uri/ =404;
}
# normal routes
# serve given url and default to index.html if not found
# e.g. /, /user and /foo/bar will return index.html
location / {
add_header Cache-Control "no-store";
try_files $uri $uri/ /index.html;
}
}
All routes matching a dot should be cached with the cache-control header and should return a 404 if not found.
Routes not matching a dot, e.g. "/users", should send the index.html by default.
However, this results in really strange behavior.
I have an index.html with the contents <h1>wazzup</h1>, and it gets correctly served when requesting a route without a dot, e.g. "/asdf":
$ curl -v localhost:8000/asdf
> Cache-Control: public, max-age=2678400
> Accept-Ranges: bytes
> ...
> <h1>wazzup</h1>
However, a Cache Control header is sent too, although this is defined in another location block. To summarize, the result is correct, but somehow the header gets mixed up. Why?
To try for yourself, you can run a docker image like so:
docker run -p 8000:80 -v /tmp/test:/app steebchen/nginx-spa
Create an index.html and script.js in the directory /tmp/test, and then access it:
curl -v localhost:8000/asdf // should return the contents of index.html
curl -v localhost:8000/script.js
The full Dockerfile is available on Github.

Answer 1

The answer is actually quite simple, I just figured it out by myself.
The second location is matching because the fallback is index.html and obviously this route contains a dot.
I simply edited the location to \.(?!html) which matches everything but html files:
location ~ \.(?!html) {
add_header Cache-Control "public, max-age=2678400";
try_files $uri $uri/ =404;
}