Proxy all subdomain to other domain path - nginx

Question

How to proxy all subdomain to other domain path?
For example
SUBDOMAIN.abcxyz123.com
To be proxied to
myapp.otherdomain.com/SUBDOMAIN
Making sure that all header/path and query parameters in the request is kept.
Update:
I've tried and have a working config but still not the one I need:
server {
listen 80;
server_name ~^(?<subdomain>.+)\.abcxyz123\.com$;
location / {
proxy_set_header Host "myapp.otherdomain.com";
proxy_set_header X-Real-IP $remote_addr;
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
proxy_http_version 1.1;
# this worked:
proxy_pass http://myapp.otherdomain.com/somepath/;
# this does not work:
#proxy_pass http://myapp.otherdomain.com/$subdomain$request_uri;
}
}

Answer 1

Try this
server {
server_name ~^(?<subdomain>.*)\.abcxyz123\.com$;
resolver 8.8.8.8;
rewrite ^/(.*)$ /$subdomain/$1;
location / {
proxy_set_header Host "myapp.otherdomain.com";
proxy_set_header X-Real-IP $remote_addr;
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
proxy_http_version 1.1;
proxy_pass http://myapp.otherdomain.com;
}
}
This should proxy all your traffic with original query parameters(query strings, request body, request method, etc), I changed the host header to the proxied "myapp.otherdomain.com" incase the server of 'myapp.otherdomain.com' has more than one virtual hosts. If you don't want the change, use $host instead.
This answer might need another edit since your question isn't very clear. If you have further question, comment and i will edit in my answer.