How to properly separate api and client part?

Question

Nginx

Hello, I can not correctly configure the config for nix.
There is a site on the server - statics that I give through nginx. And an application (API server) is launched that runs on port 8081.
Now I can’t figure out how to catch requests for example domain.com/api/ and send them to the backend (port 8081)
I thought to make a subdomain api.domain.com, but I can’t at all everything is a miracle to set up. Tried different options, but nothing works.
Thanks in advance :3

Answer 1

the simplest config for redirecting requests to the backend

...
location /api {
    proxy_pass http://localhost:8081;
}
...

Answer 2

I solved the problem with this config:

server {
  listen 80 default_server;
  listen [::]:80 default_server;
  server_name mydomain.ru www.mydomain.ru;

  return 301 https://$server_name$request_uri;
}

# the main server directive for ssl connections
# where we also use http2 (see asset delivery)
server {
  listen 443 ssl http2 default_server;
  listen [::]:443 ssl http2 default_server;
  server_name mydomain.ru www.mydomain.ru;

  # paths to certificate and key provided by Let's Encrypt
  ssl_certificate /etc/letsencrypt/live/mydomain.ru/fullchain.pem;
  ssl_certificate_key /etc/letsencrypt/live/mydomain.ru/privkey.pem;

  # SSL settings that currently offer good results in the SSL check
  # and have a reasonable backwards-compatibility, taken from
  # - https://cipherli.st/
  # - https://raymii.org/s/tutorials/Strong_SSL_Security_On_nginx.html
  ssl_protocols TLSv1 TLSv1.1 TLSv1.2;
  ssl_prefer_server_ciphers on;
  ssl_ecdh_curve secp384r1;
  ssl_session_cache shared:SSL:10m;
  ssl_session_tickets off;
  ssl_stapling on;
  ssl_stapling_verify on;
  ssl_dhparam /etc/ssl/certs/dhparam.pem;

  # security enhancements
  add_header Strict-Transport-Security "max-age=63072000; includeSubdomains";
  add_header X-Frame-Options DENY;
  add_header X-Content-Type-Options nosniff;

  # Let's Encrypt keeps its files here
  location ~ /.well-known {
    root /var/www/html;
    allow all;
  }

  # besides referencing the extracted upstream this stays the same
  location /api {
    proxy_set_header X-Real-IP $remote_addr;
    proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
    proxy_set_header Host $http_host;
    proxy_redirect off;
    proxy_pass http://127.0.0.1:8081;
    proxy_set_header Upgrade $http_upgrade;
    proxy_set_header Connection "upgrade";
  }
  location / {
    root /var/www/html;
    index index.html;
  }
}