Handshake failed due to invalid Upgrade header: null 解决方案

　　微信小程序webSocket使用，本地开发环境没问题，QA环境报错：

org.springframework.web.socket.server.support.DefaultHandshakeHandler : Handshake failed due to invalid Upgrade header: null

　　前端报错：

failed: Error during WebSocket handshake: Unexpected response code: 400

　　通过比较后发现，QA环境使用nginx反向代理服务器忽略了headers中的：Upgrade:websocket。

　　解决办法：在  Nginx  ，location 中添加如下红色代码：

　　proxy_set_header Upgrade $http_upgrade;

　　proxy_set_header Connection  "upgrade";

 1 server {  2  listen 80;  3  server_name localhost;  4  
 5  
 6  location / {  7  proxy_set_header X-Real-IP $remote_addr;  8  proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;  9  proxy_set_header Host $http_host; 10  proxy_set_header X-NginX-Proxy true; 11  
12  # prevents 502 bad gateway error 13  proxy_buffers 8 32k; 14  proxy_buffer_size 64k; 15  
16  proxy_pass http://127.0.0.1:8080; 17  proxy_redirect off; 18  
19  # enables WS support 20  proxy_http_version 1.1; 21  proxy_set_header Upgrade $http_upgrade; 22  proxy_set_header Connection "upgrade"; 23  } 24 }

　　使得请求中包含Upgrade。