worker_processes     auto;  ## Default: 1
worker_rlimit_nofile 8192;

events {
  worker_connections  1024;  ## Default: 1024
}

http {
  sendfile             on;
  tcp_nopush           on;
  log_not_found        off;
  gzip                 on;
  include              mime.types; # web pages might not be rendered properly if mime.types not included
  default_type         application/octet-stream;
  client_max_body_size 500M;
  keepalive_timeout    30s;

  upstream backend {
    server localhost:9001;
  }

  # the Connection header will be correctly set to close when the Upgrade header in the request is set to ''.
  map $http_upgrade $connection_upgrade {
    default upgrade;
    '' close;
  } 

  server {
    listen 9000;

    # This is the default block since / matches all requests.
    # It should be used to serve static files. 
    location / {
      # Search ./resources/xxx first; 
      # if not found, search ./resources/index.html instead; 
      # if still not found, respond 404.
      root      ./resources;
      try_files $uri /index.html =404;
    }

    # Both the trailing slashes in location and proxy_pass matter 
    # because if the proxy_pass directive is specified with a URI, 
    # then when a request is passed to the server, 
    # the part of a normalized request URI matching the location is replaced by a URI specified in the directive
    location /api/ {
      # /api/** will be forwarded to http://backend/**
      proxy_pass http://backend/;
      # For NGINX to send the Upgrade request from the client to the backend server,
      # the Upgrade and Connection headers must be set explicitly
      proxy_set_header Upgrade $http_upgrade;
      proxy_set_header Connection $connection_upgrade;
    }

    location = /allocation/assignment { # This is an exact match.
      # /allocation/assignment will be forwarded to http://backend/allocation/assignment
      proxy_pass http://backend;
    }

    location /get/ {
      # /get/** will be forwarded to http://backend/get/**
      proxy_pass http://backend;
    }

    location = /export/taskTableDataExport {
      proxy_pass http://backend;
    }

    location = /task/createTaskByXmlFile {
      proxy_pass http://backend;
    }
  }
}