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

　　经过比较后发现，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 中添加以下红色代码：

　　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 error13                 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 support20                 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。