Niginx location with cache for a specific url with params - caching

Question

I'd like to use nginx cache for a specific url only
The url is /ajax/airport and must contain the parameter ?geoloc=1.
Cache is working fine, the only issue I'm facing is to get it working for an url containing the given parameters.
Here is my nginx site.conf file:
server {
listen 80;
server_name _;
server_tokens off;
location /ajax/airport.php {
if ($args_geoloc = 1) {
proxy_pass http://127.0.0.1:8080/ajax/airport.php;
proxy_set_header Host $host;
proxy_set_header X-Real-IP $remote_addr;
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
proxy_cache my-cache;
proxy_cache_valid 300s;
#proxy_no_cache $cookie_PHPSESSID;
#proxy_cache_bypass $cookie_PHPSESSID;
proxy_cache_key "$scheme$host$request_uri";
add_header X-Cache $upstream_cache_status;
add_header LEM airport;
}
}
location / {
proxy_pass http://127.0.0.1:8080/;
proxy_set_header Host $host;
proxy_set_header X-Real-IP $remote_addr;
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
add_header LEM all;
}
}
server {
listen 8080;
.. usual location handeling ...
And the error I get:
nginx: [emerg] "proxy_pass" cannot have URI part in location given by regular expression, or inside named location, or inside "if" statement, or inside "limit_except" block in /etc/nginx/sites-enabled/site.com.conf:8
Thank you for your help!

Answer 1

Simply use proxy_no_cache and proxy_cache_bypass instead of if, testing the value of $arg_geoloc (not $args_geoloc) with map directive.
map $arg_geoloc $bypass {
default 1;
1 0;
}
server {
...
location /ajax/airport.php {
...
proxy_no_cache $bypass;
proxy_cache_bypass $bypass;
...
# No need to add /ajax/airport.php in proxy_pass
proxy_pass http://127.0.0.1:8080;
}
...
}
Nginx also allows to test several parameters with proxy_no_cache and proxy_cache_bypass. If you need something like that just put the parameters one after another:
proxy_no_cache $cookie_PHPSESSID $bypass_cache;
proxy_cache_bypass $cookie_PHPSESSID $bypass_cache;