nginx 根据请求参数动态proxy_pass后端域名

方法一

server {
  listen 80;
  server_name __proxy_resolver__;
  resolver 223.5.5.5;

  # /?proxy_schema=http&proxy_host=x.x.x.x:8080&proxy_url=/XXX/api?tId=123456&fooid=1234

 set $proxy_schema 'http';
  set $proxy_host '';
  set $proxy_url '';
  if ( $request_uri ~ (proxy_schema=([^&]+))){
      set $proxy_schema $2;
  }
  if ( $request_uri ~ (proxy_host=([^&]+))){
    set $proxy_host $2;
  }
  if ($request_uri ~ (proxy_url=(.*)$)){
    set $proxy_url $2;
  }
  if ($proxy_url = '') {
    return 404;
  }
  if ($proxy_host = '') {
    return 404;
  }
  location / {
    proxy_pass $proxy_schema://$proxy_host$proxy_url;
  }  
  
}

方法二

http://192.168.174.120/wbimg/?url=https://192.168.174.121/orj360/005UGUPIly1gwikvqim9rj31401404aa.jpg

server {
  listen 80;
  server_name 192.168.174.120;
  resolver 223.5.5.5;
  
  location /~wbimg {
    if ($query_string ~* ^(.*)url=(.*)$) {
      set $url_ $2; #$2=https://192.168.174.121/orj360/005UGUPIly1gwikvqim9rj31401404aa.jpg
    }
    proxy_set_header Referer "https://weibo.com";
    proxy_pass $url_;
  }
}