详解Nginx反向代理WebSocket响应403的解决办法

在Nginx反向代理一个带有WebSocket功能的Spring Web程序（源代码地址 ）时，发现访问WebSocket接口时总是出现403响应，Nginx的配置参考的是 官方文档 :

http {
  // ssl 相关配置 ...
  
  map $http_upgrade $connection_upgrade {
    default upgrade;
    '' close;
  }

  server {
    listen 8020;
    location /ws {
      proxy_pass http://some-ip:8080;
      proxy_http_version 1.1;
      proxy_set_header Upgrade $http_upgrade;
      proxy_set_header Connection $connection_upgrade;
    }
  }
}

唯一不同的是我们的Nginx配置了https。

于是打开Spring日志查看直接访问和通过Nginx访问的差别。

直接访问的日志：

DEBUG ... o.s.web.servlet.DispatcherServlet    : DispatcherServlet with name 'dispatcherServlet' processing GET request for [/ws/gs-guide-websocket/786/kz0qai5l/websocket]
DEBUG ... s.w.s.m.m.a.RequestMappingHandlerMapping : Looking up handler method for path /gs-guide-websocket/786/kz0qai5l/websocket
DEBUG ... s.w.s.m.m.a.RequestMappingHandlerMapping : Did not find handler method for [/gs-guide-websocket/786/kz0qai5l/websocket]
DEBUG ... o.s.w.s.s.s.WebSocketHandlerMapping   : Matching patterns for request [/gs-guide-websocket/786/kz0qai5l/websocket] are [/gs-guide-websocket/**]
DEBUG ... o.s.w.s.s.s.WebSocketHandlerMapping   : URI Template variables for request [/gs-guide-websocket/786/kz0qai5l/websocket] are {}
DEBUG ... o.s.w.s.s.s.WebSocketHandlerMapping   : Mapping [/gs-guide-websocket/786/kz0qai5l/websocket] to HandlerExecutionChain with handler [org.springframework.web.socket.sockjs.support.SockJsHttpRequestHandler@307f6b8c] and 1 interceptor
DEBUG ... o.s.web.servlet.DispatcherServlet    : Last-Modified value for [/ws/gs-guide-websocket/786/kz0qai5l/websocket] is: -1
DEBUG ... o.s.web.cors.DefaultCorsProcessor    : Skip CORS processing: request is from same origin
DEBUG ... o.s.w.s.s.t.h.DefaultSockJsService    : Processing transport request: GET http://localhost:8080/ws/gs-guide-websocket/786/kz0qai5l/websocket
DEBUG ... o.s.web.servlet.DispatcherServlet    : Null ModelAndView returned to DispatcherServlet with name 'dispatcherServlet': assuming HandlerAdapter completed request handling
DEBUG ... o.s.web.servlet.DispatcherServlet    : Successfully completed request

通过Nginx访问的日志：

DEBUG ... o.s.web.servlet.DispatcherServlet    : DispatcherServlet with name 'dispatcherServlet' processing GET request for [/ws/gs-guide-websocket/297/jp1c3ab5/websocket]
DEBUG ... s.w.s.m.m.a.RequestMappingHandlerMapping : Looking up handler method for path /gs-guide-websocket/297/jp1c3ab5/websocket
DEBUG ... s.w.s.m.m.a.RequestMappingHandlerMapping : Did not find handler method for [/gs-guide-websocket/297/jp1c3ab5/websocket]
DEBUG ... o.s.w.s.s.s.WebSocketHandlerMapping   : Matching patterns for request [/gs-guide-websocket/297/jp1c3ab5/websocket] are [/gs-guide-websocket/**]
DEBUG ... o.s.w.s.s.s.WebSocketHandlerMapping   : URI Template variables for request [/gs-guide-websocket/297/jp1c3ab5/websocket] are {}
DEBUG ... o.s.w.s.s.s.WebSocketHandlerMapping   : Mapping [/gs-guide-websocket/297/jp1c3ab5/websocket] to HandlerExecutionChain with handler [org.springframework.web.socket.sockjs.support.SockJsHttpRequestHandler@307f6b8c] and 1 interceptor
DEBUG ... o.s.web.servlet.DispatcherServlet    : Last-Modified value for [/ws/gs-guide-websocket/297/jp1c3ab5/websocket] is: -1
DEBUG ... o.s.w.s.s.t.h.DefaultSockJsService    : Processing transport request: GET http://localhost:8080/ws/gs-guide-websocket/297/jp1c3ab5/websocket
DEBUG ... o.s.w.s.s.s.OriginHandshakeInterceptor  : Handshake request rejected, Origin header value https://some-host.com not allowed
DEBUG ... o.s.w.s.s.s.HandshakeInterceptorChain  : org.springframework.web.socket.server.support.OriginHandshakeInterceptor@25ce6ad4 returns false from beforeHandshake - precluding handshake
DEBUG ... o.s.web.servlet.DispatcherServlet    : Null ModelAndView returned to DispatcherServlet with name 'dispatcherServlet': assuming HandlerAdapter completed request handling
DEBUG ... o.s.web.servlet.DispatcherServlet    : Successfully completed request

注意到直接访问的日志里有这么一条：

代码如下：

DEBUG ... o.s.web.cors.DefaultCorsProcessor : Skip CORS processing: request is from same origin

通过Nginx访问的日志里有这么一条：

代码如下：

DEBUG ... o.s.w.s.s.s.OriginHandshakeInterceptor   : Handshake request rejected, Origin header value https://some-host.com not allowed

然后Google查询相关解决办法，找到github上的这个 issue ，所以只需要修改Nginx的配置，添加 proxy_set_header Origin ""; 就行了：

http {
  // ssl 相关配置 ...
  
  map $http_upgrade $connection_upgrade {
    default upgrade;
    '' close;
  }

  server {
    listen 8020;
    location /ws {
      proxy_pass http://some-ip:8080;
      proxy_http_version 1.1;
      proxy_set_header Upgrade $http_upgrade;
      proxy_set_header Connection $connection_upgrade;
      proxy_set_header Origin "";
    }
  }
}