Spring Cloud Gateway转发下游API请求存在延迟问题求助

问题背景 #

已配置Spring Cloud Gateway转发请求至下游API，但存在两个核心问题：

1. 部分请求转发耗时超5秒，导致依赖服务因超时返回错误，最终出现java.io.IOException: An existing connection was forcibly closed by the remote host错误
2. 仅配置了POST请求路由，但仍有GET请求到达网关，需拦截此类请求

已排除服务器资源负载问题，调大JVM堆内存参数无效。

原始错误日志 #

2024-03-12 01:21:12.174 DEBUG 7104 --- [tor-http-nio-13] reactor.netty.http.server.HttpServer     : [5b39460c-1, L:/Local IP:8058 - R:/10.216.130.23:14454] Handler is being applied: org.springframework.http.server.reactive.ReactorHttpHandlerAdapter@2bd948e4
2024-03-12 01:21:12.174 DEBUG 7104 --- [tor-http-nio-13] o.s.w.s.adapter.HttpWebHandlerAdapter    : [5b39460c-2530] HTTP POST "/wallet/v1/wallet/qr/payment/auth"
2024-03-12 01:21:12.174  INFO 7104 --- [tor-http-nio-13] c.d.epiCloudproxy.LoggingFilter  : Routing Incoming request orginal url Local API Endpoint route to url: api endpoint,
2024-03-12 01:21:12.174 DEBUG 7104 --- [ctor-http-nio-1] r.n.resources.PooledConnectionProvider   : [c5448fc1, L:/Local IP:54766 - R:Remote IP:9480] Channel acquired, now: 1 active connections, 0 inactive connections and 0 pending acquire requests.
2024-03-12 01:21:12.174 DEBUG 7104 --- [ctor-http-nio-1] r.netty.http.client.HttpClientConnect    : [c5448fc1-2, L:/Local IP:54766 - R:Remote IP:9480] Handler is being applied: {uri=api endpoint, method=POST}
2024-03-12 01:21:12.174 DEBUG 7104 --- [ctor-http-nio-1] r.n.r.DefaultPooledConnectionProvider    : [c5448fc1-2, L:/Local IP:54766 - R:Remote IP:9480] onStateChange(POST{uri=/v1/wallet/qr/payment/auth, connection=PooledConnection{channel=[id: 0xc5448fc1, L:/Local IP:54766 - R:Remote IP:9480]}}, [request_prepared])
2024-03-12 01:21:12.174 DEBUG 7104 --- [tor-http-nio-13] reactor.netty.channel.FluxReceive        : [5b39460c-1, L:/Local IP:8058 - R:/10.216.130.23:14454] [terminated=true, cancelled=false, pending=1, error=null]: subscribing inbound receiver
2024-03-12 01:21:12.174 DEBUG 7104 --- [ctor-http-nio-1] r.n.r.DefaultPooledConnectionProvider    : [c5448fc1-2, L:/Local IP:54766 - R:Remote IP:9480] onStateChange(POST{uri=/v1/wallet/qr/payment/auth, connection=PooledConnection{channel=[id: 0xc5448fc1, L:/Local IP:54766 - R:Remote IP:9480]}}, [request_sent])
2024-03-12 01:21:21.940 DEBUG 7104 --- [tor-http-nio-14] reactor.netty.tcp.SslProvider            : [0510b3b7, L:/Local IP:8058 - R:/10.216.130.22:55058] SSL enabled using engine 410137f5[SSLEngine[hostname=null port=-1] SSL_NULL_WITH_NULL_NULL]
2024-03-12 01:21:21.940 DEBUG 7104 --- [tor-http-nio-14] r.n.http.server.HttpServerOperations     : [0510b3b7, L:/Local IP:8058 - R:/10.216.130.22:55058] New http connection, requesting read
2024-03-12 01:21:21.940 DEBUG 7104 --- [tor-http-nio-14] reactor.netty.transport.TransportConfig  : [0510b3b7, L:/Local IP:8058 - R:/10.216.130.22:55058] Initialized pipeline DefaultChannelPipeline{(reactor.left.sslHandler = io.netty.handler.ssl.SslHandler), (reactor.left.sslReader = reactor.netty.tcp.SslProvider$SslReadHandler), (reactor.left.httpCodec = io.netty.handler.codec.http.HttpServerCodec), (reactor.left.httpTrafficHandler = reactor.netty.http.server.HttpTrafficHandler), (reactor.right.reactiveBridge = reactor.netty.channel.ChannelOperationsHandler)}
2024-03-12 01:21:21.940 DEBUG 7104 --- [tor-http-nio-14] r.n.http.server.HttpServerOperations     : [0510b3b7, L:/Local IP:8058 - R:/10.216.130.22:55058] Increasing pending responses, now 1
2024-03-12 01:21:21.940 DEBUG 7104 --- [tor-http-nio-14] reactor.netty.http.server.HttpServer     : [0510b3b7-1, L:/Local IP:8058 - R:/10.216.130.22:55058] Handler is being applied: org.springframework.http.server.reactive.ReactorHttpHandlerAdapter@2bd948e4
2024-03-12 01:21:21.940 DEBUG 7104 --- [tor-http-nio-14] o.s.w.s.adapter.HttpWebHandlerAdapter    : [0510b3b7-2531] HTTP GET "/"
2024-03-12 01:21:21.940 DEBUG 7104 --- [tor-http-nio-14] o.s.w.r.handler.SimpleUrlHandlerMapping  : [0510b3b7-2531] Mapped to ResourceWebHandler [classpath [META-INF/resources/], classpath [resources/], classpath [static/], classpath [public/]]
2024-03-12 01:21:21.940 DEBUG 7104 --- [tor-http-nio-14] o.s.w.r.resource.ResourceWebHandler      : [0510b3b7-2531] Resource not found
2024-03-12 01:21:21.940 DEBUG 7104 --- [tor-http-nio-14] org.springframework.web.HttpLogging      : [0510b3b7-2531] Resolved [ResponseStatusException: 404 NOT_FOUND] for HTTP GET /
2024-03-12 01:21:21.940 DEBUG 7104 --- [tor-http-nio-14] org.springframework.web.HttpLogging      : [0510b3b7-2531] Encoding [{timestamp=Tue Mar 12 01:21:21 GST 2024, path=/, status=404, error=Not Found, message=null, requestI (truncated)...]
2024-03-12 01:21:21.940 DEBUG 7104 --- [tor-http-nio-14] r.n.http.server.HttpServerOperations     : [0510b3b7-1, L:/Local IP:8058 - R:/10.216.130.22:55058] Detected non persistent http connection, preparing to close
2024-03-12 01:21:21.940 DEBUG 7104 --- [tor-http-nio-14] r.n.http.server.HttpServerOperations     : [0510b3b7-1, L:/Local IP:8058 - R:/10.216.130.22:55058] Last HTTP packet was sent, terminating the channel
2024-03-12 01:21:21.940 DEBUG 7104 --- [tor-http-nio-14] reactor.netty.channel.ChannelOperations  : [0510b3b7-1, L:/Local IP:8058 - R:/10.216.130.22:55058] [HttpServer] Channel inbound receiver cancelled (operation cancelled).
2024-03-12 01:21:21.940 DEBUG 7104 --- [tor-http-nio-14] o.s.w.s.adapter.HttpWebHandlerAdapter    : [0510b3b7-2531] Completed 404 NOT_FOUND
2024-03-12 01:21:31.128  WARN 7104 --- [ctor-http-nio-1] r.netty.http.client.HttpClientConnect    : [c5448fc1-2, L:/Local IP:54766 - R:Remote IP:9480] The connection observed an error

当前配置文件 #

server:
  ssl:
    key-store: cert.p12
    key-store-password: pw
    key-alias: alias
    key-store-type: PKCS12
  port: 8058
  
logging:
  level:
    reactor:
      netty: DEBUG
    org:
      springframework:
        web: DEBUG
  
spring:
  cloud:
    gateway:
      httpclient:
        proxy:
          port: 9480
          host: cloudproxy
      routes:
      - id: test-route
        uri: Remote_uri
        predicates:
        - Path=/reqbin/**
        filters:
        - RewritePath=/reqbin/(?<path>.*), /$\{path}
      - id: fill_go_routes
        uri: Remote_uri
        predicates:
        - Path=/fill-go/**
        filters:
        - RewritePath=/fill-go/(?<path>.*), /$\{path}
      - id: qr_wallet_routes
        uri: Remote_uri
        predicates:
        - Path=/wallet/**
        filters:
        - RewritePath=/wallet/(?<path>.*), /$\{path} 

解决方案 #

一、解决请求延迟与连接被强制关闭问题 #

从日志可见，POST请求发送后约19秒才触发连接错误，核心原因是网关未配置合理的超时参数，导致请求等待至被代理或下游服务强制断开。

1. 添加HttpClient超时配置
   在spring.cloud.gateway.httpclient下补充超时参数，与依赖服务的5秒超时保持一致：

spring:
  cloud:
    gateway:
      httpclient:
        connect-timeout: 5000 # 连接超时5秒
        response-timeout: 5000 # 响应超时5秒
        pool:
          max-idle-time: 10000 # 连接池最大空闲时间10秒
          max-life-time: 30000 # 连接最大存活时间30秒
          max-connections: 200 # 根据业务并发量调整最大连接数

此配置能避免请求因等待过久被强制关闭，同时优化连接池复用效率。

2. 排查代理与下游服务网络

• 检查代理服务器到下游API的网络链路是否存在丢包、延迟过高问题
• 确认下游服务的超时配置，确保网关超时不超过下游服务的超时阈值
• 若下游服务偶尔超时，可添加重试过滤器（注意避免重复提交幂等性问题）：

filters:
- name: Retry
  args:
    retries: 2
    methods: POST
    statuses: BAD_GATEWAY, SERVICE_UNAVAILABLE

二、拦截未配置的GET请求 #

当前路由仅通过Path匹配，未限制请求方法，导致GET请求会被默认资源处理器处理。可通过两种方式拦截：

1. 给现有路由添加Method断言
   修改每个路由的predicates，仅允许POST请求匹配：

- id: qr_wallet_routes
  uri: Remote_uri
  predicates:
  - Path=/wallet/**
  - Method=POST # 仅接受POST请求
  filters:
  - RewritePath=/wallet/(?<path>.*), /$\{path}

未匹配的GET请求会返回404或被后续路由处理。

2. 全局拦截所有GET请求
   添加优先级最高的路由，直接拒绝所有GET请求：

spring:
  cloud:
    gateway:
      routes:
      - id: block-all-get
        uri: no://op
        predicates:
        - Method=GET
        filters:
        - name: SetStatus
          args:
            status: 403 # 返回403禁止访问
      # 现有路由放在后面
      - id: test-route
        uri: Remote_uri
        ...

注意此路由需放在所有路由最前面，Spring Cloud Gateway会按顺序匹配路由。

内容的提问来源于stack exchange，提问作者Hussain lala