Set proxy_pass in nginx based on request_method - nginx

Question

I have two application and a nginx server on top of that. I want to proxy all GET requests coming on nginx to one app running on http://127.0.0.1:9101/ and proxy all other request methods to http://10.41.115.241:8000/
I have tried couple of options but none worked
I have tried using limit_exempt
location /api/v1/executions {
error_page 502 = #apiError;
rewrite ^/api/(.*) /$1 break;
proxy_pass http://127.0.0.1:9101/;
limit_except PUT POST DELETE {
proxy_pass http://10.41.115.241:8000/;
}
proxy_read_timeout 90;
proxy_connect_timeout 90;
proxy_redirect off;
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_set_header Connection '';
chunked_transfer_encoding off;
proxy_buffering off;
proxy_cache off;
#proxy_set_header Host $host;
}
I have also tried if condition
location /api/v1/executions {
error_page 502 = #apiError;
rewrite ^/api/(.*) /$1 break;
proxy_pass http://10.41.115.241:8000/;
if ($request_method = GET) {
proxy_pass http://127.0.0.1:9101/;
}
proxy_read_timeout 90;
proxy_connect_timeout 90;
proxy_redirect off;
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_set_header Connection '';
chunked_transfer_encoding off;
proxy_buffering off;
proxy_cache off;
#proxy_set_header Host $host;
}
but in both ways I got this error
"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 /path/to/config

Answer 1

Always try to use map instead of if for conditional logic in NGINX. Unless it's absolutely impossible with map.. In your particular case, it's easy.
Create a variable $backend which will hold your desired proxy_pass value depending on the request methods:
http {
map $request_method $backend {
default http://10.41.115.241:8000/;
GET http://127.0.0.1:9101/;
}
...
}
Then use it you in your config:
location /api/v1/executions {
error_page 502 = #apiError;
rewrite ^/api/(.*) /$1 break;
proxy_pass $backend;
proxy_read_timeout 90;
proxy_connect_timeout 90;
proxy_redirect off;
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_set_header Connection '';
chunked_transfer_encoding off;
proxy_buffering off;
proxy_cache off;
#proxy_set_header Host $host;
}