Nginx REST API and SPA configuration

nginx_api_spa.conf

map $http_upgrade $connection_upgrade {
    default upgrade;
    '' close;
  }


server {
    listen       80;
    server_name  _;

      location /api/ {
       add_header 'Access-Control-Allow-Origin' '*';
       add_header 'Access-Control-Allow-Credentials' 'true';
       add_header 'Access-Control-Allow-Headers' 'Authorization,Accept,Origin,DNT,X-CustomHeader,Keep-Alive,User-Agent,X-Requested-With,If-Modified-Since,Cache-Control,Content-Type,Content-Range,Range';
       add_header 'Access-Control-Allow-Methods' 'GET,POST,OPTIONS,PUT,DELETE,PATCH';
       proxy_pass http://backend:8000;
       proxy_set_header Host $http_host;
       proxy_set_header X-Forwarded-Proto $scheme;
    }

    location / {
       # Uncomment for production build
        #root   /front;
        #index  index.html index.htm;
       # Comment line below in production deployment
       proxy_pass http://spa:3000;
       proxy_http_version 1.1;
       proxy_set_header Host $http_host;
       proxy_set_header X-Forwarded-Proto $scheme;
       proxy_set_header Upgrade $http_upgrade;
       proxy_set_header Connection $connection_upgrade;
    }

    #error_page  404              /404.html;

    # redirect server error pages to the static page /50x.html
    #
    error_page   500 502 503 504  /50x.html;
    location = /50x.html {
        root   /usr/share/nginx/html;
    }
}