Nginx反向代理Websocket域名访问

upstream frontends {
    # Websocket地址
    server 127.0.0.1:4702;
}
server {
    # 指向域名
    server_name www.abc.com;
    location / {
        proxy_pass http://frontends;
        proxy_set_header Host $host;
        proxy_set_header X-Real-IP $remote_addr;
        proxy_set_header X-Forwarded-For $remote_addr;
        proxy_http_version 1.1;
        proxy_set_header Upgrade $http_upgrade;
        proxy_set_header Connection "upgrade";
    }
}