CODEWITHSUNDEEP
springkubernetesspring-cloudspring-cloud-gateway
Vishal
Vishal

Reputation: 589

Spring cloud gateway route to service in another namespace

I have a spring-boot application running and using spring cloud gateway. The app is running on kubernetes (Tried on EKS as well as local docker desktop). I am having trouble accessing a route which is pointing to a service in another namespace (non default). When I launch http://localhost:8080/actuator/gateway/routes I see the route below as one of the routes

{
predicate: "Paths: [/my-app/**], match trailing slash: true",
metadata: {
  port.http: "8080",
  k8s_namespace: "customns",
  app.kubernetes.io/name: "my-app",
  spring-boot: "yes",
  kubectl.kubernetes.io/last-applied-configuration: "{"apiVersion":"v1","kind":"Service","metadata":{"annotations":{},"labels":{"app.kubernetes.io/name":"my-app","platform":"no","spring-boot":"yes"},"name":"my-app","namespace":"customns"},"spec":{"ports":[{"name":"http","port":8082,"targetPort":8080}],"selector":{"app.kubernetes.io/name":"my-app"},"type":"LoadBalancer"}} ",
  platform: "no"
},
route_id: "ReactiveCompositeDiscoveryClient_my-app",
filters: [
"[[RewritePath /my-app/(?<remaining>.*) = '/${remaining}'], order = 1]"
],
uri: "lb://my-app",
order: 0
}

And in the application.yml, I have added the below gateway route

spring:
  main:
    banner-mode: off
  cloud:
    kubernetes:
      discovery:
        enabled: true
        all-namespaces: true
    gateway:
      discovery:
        locator:
          enabled: true
          lower-case-service-id: true
      metrics:
        enabled: true
      routes:
        - id: my-app
          uri: lb://my-app
          predicates:
            - Path=/my-custom-url/**
          filters:
            - RewritePath=/my-custom-url(?<segment>/?.*), $\{segment}

However when I launch http://localhost:8080/my-app or http://localhost:8080/my-custom-url, I get error like below

2021-03-04 16:18:24.201 ERROR [my-gateway-service,,] 1 --- [or-http-epoll-4] a.w.r.e.AbstractErrorWebExceptionHandler : [9a85e6b2-7]  500 Server Error for HTTP GET "/my-app"

java.lang.IllegalArgumentException: The path does not have a leading slash.
        at org.springframework.util.Assert.isTrue(Assert.java:121) ~[spring-core-5.3.3.jar:5.3.3]
        Suppressed: reactor.core.publisher.FluxOnAssembly$OnAssemblyException:
Error has been observed at the following site(s):
        |_ checkpoint ⇢ org.springframework.cloud.gateway.filter.WeightCalculatorWebFilter [DefaultWebFilterChain]
        |_ checkpoint ⇢ org.springframework.security.web.server.authorization.AuthorizationWebFilter [DefaultWebFilterChain]
        |_ checkpoint ⇢ org.springframework.security.web.server.authorization.ExceptionTranslationWebFilter [DefaultWebFilterChain]
        |_ checkpoint ⇢ org.springframework.security.web.server.authentication.logout.LogoutWebFilter [DefaultWebFilterChain]
        |_ checkpoint ⇢ org.springframework.security.web.server.savedrequest.ServerRequestCacheWebFilter [DefaultWebFilterChain]
        |_ checkpoint ⇢ org.springframework.security.web.server.context.SecurityContextServerWebExchangeWebFilter [DefaultWebFilterChain]
        |_ checkpoint ⇢ org.springframework.security.web.server.ui.LogoutPageGeneratingWebFilter [DefaultWebFilterChain]
        |_ checkpoint ⇢ org.springframework.security.web.server.ui.LoginPageGeneratingWebFilter [DefaultWebFilterChain]
        |_ checkpoint ⇢ org.springframework.security.oauth2.client.web.server.authentication.OAuth2LoginAuthenticationWebFilter [DefaultWebFilterChain]
        |_ checkpoint ⇢ org.springframework.security.oauth2.client.web.server.OAuth2AuthorizationRequestRedirectWebFilter [DefaultWebFilterChain]
        |_ checkpoint ⇢ org.springframework.security.web.server.context.ReactorContextWebFilter [DefaultWebFilterChain]
        |_ checkpoint ⇢ org.springframework.security.web.server.header.HttpHeaderWriterWebFilter [DefaultWebFilterChain]
        |_ checkpoint ⇢ org.springframework.security.config.web.server.ServerHttpSecurity$ServerWebExchangeReactorContextWebFilter [DefaultWebFilterChain]
        |_ checkpoint ⇢ org.springframework.security.web.server.WebFilterChainProxy [DefaultWebFilterChain]
        |_ checkpoint ⇢ org.springframework.cloud.sleuth.instrument.web.TraceWebFilter [DefaultWebFilterChain]
        |_ checkpoint ⇢ org.springframework.boot.actuate.metrics.web.reactive.server.MetricsWebFilter [DefaultWebFilterChain]
        |_ checkpoint ⇢ HTTP GET "/my-app" [ExceptionHandlingWebHandler]
Stack trace:
                at org.springframework.util.Assert.isTrue(Assert.java:121) ~[spring-core-5.3.3.jar:5.3.3]
                at org.springframework.http.server.reactive.DefaultServerHttpRequestBuilder.path(DefaultServerHttpRequestBuilder.java:95) ~[spring-web-5.3.3.jar:5.3.3]
                at org.springframework.cloud.gateway.filter.factory.RewritePathGatewayFilterFactory$1.filter(RewritePathGatewayFilterFactory.java:70) ~[spring-cloud-gateway-server-3.0.0.jar:3.0.0]
                at org.springframework.cloud.gateway.filter.OrderedGatewayFilter.filter(OrderedGatewayFilter.java:44) ~[spring-cloud-gateway-server-3.0.0.jar:3.0.0]
                at org.springframework.cloud.gateway.handler.FilteringWebHandler$DefaultGatewayFilterChain.lambda$filter$0(FilteringWebHandler.java:117) ~[spring-cloud-gateway-server-3.0.0.jar:3.0.0]
                at reactor.core.publisher.MonoDefer.subscribe(MonoDefer.java:44) ~[reactor-core-3.4.2.jar:3.4.2]
                at reactor.core.publisher.InternalMonoOperator.subscribe(InternalMonoOperator.java:64) ~[reactor-core-3.4.2.jar:3.4.2]
                at reactor.core.publisher.MonoDefer.subscribe(MonoDefer.java:52) ~[reactor-core-3.4.2.jar:3.4.2]
                at reactor.core.publisher.MonoDefer.subscribe(MonoDefer.java:52) ~[reactor-core-3.4.2.jar:3.4.2]
                at reactor.core.publisher.Mono.subscribe(Mono.java:4046) ~[reactor-core-3.4.2.jar:3.4.2]
                at reactor.core.publisher.MonoIgnoreThen$ThenIgnoreMain.drain(MonoIgnoreThen.java:173) ~[reactor-core-3.4.2.jar:3.4.2]
                at reactor.core.publisher.MonoIgnoreThen.subscribe(MonoIgnoreThen.java:56) ~[reactor-core-3.4.2.jar:3.4.2]
                at reactor.core.publisher.InternalMonoOperator.subscribe(InternalMonoOperator.java:64) ~[reactor-core-3.4.2.jar:3.4.2]
                :
                :
                :
                at io.netty.channel.CombinedChannelDuplexHandler$DelegatingChannelHandlerContext.fireChannelRead(CombinedChannelDuplexHandler.java:436) ~[netty-transport-4.1.58.Final.jar:4.1.58.Final]
                at io.netty.handler.codec.ByteToMessageDecoder.fireChannelRead(ByteToMessageDecoder.java:324) ~[netty-codec-4.1.58.Final.jar:4.1.58.Final]
                at io.netty.handler.codec.ByteToMessageDecoder.channelRead(ByteToMessageDecoder.java:296) ~[netty-codec-4.1.58.Final.jar:4.1.58.Final]
                at io.netty.channel.CombinedChannelDuplexHandler.channelRead(CombinedChannelDuplexHandler.java:251) ~[netty-transport-4.1.58.Final.jar:4.1.58.Final]
                at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:379) ~[netty-transport-4.1.58.Final.jar:4.1.58.Final]
                at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:365) ~[netty-transport-4.1.58.Final.jar:4.1.58.Final]
                at io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:357) ~[netty-transport-4.1.58.Final.jar:4.1.58.Final]
                at io.netty.channel.DefaultChannelPipeline$HeadContext.channelRead(DefaultChannelPipeline.java:1410) ~[netty-transport-4.1.58.Final.jar:4.1.58.Final]
                at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:379) ~[netty-transport-4.1.58.Final.jar:4.1.58.Final]
                at io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:365) ~[netty-transport-4.1.58.Final.jar:4.1.58.Final]
                at io.netty.channel.DefaultChannelPipeline.fireChannelRead(DefaultChannelPipeline.java:919) ~[netty-transport-4.1.58.Final.jar:4.1.58.Final]
                at io.netty.channel.epoll.AbstractEpollStreamChannel$EpollStreamUnsafe.epollInReady(AbstractEpollStreamChannel.java:795) ~[netty-transport-native-epoll-4.1.58.Final-linux-x86_64.jar:4.1.58.Final]
                at io.netty.channel.epoll.EpollEventLoop.processReady(EpollEventLoop.java:480) ~[netty-transport-native-epoll-4.1.58.Final-linux-x86_64.jar:4.1.58.Final]
                at io.netty.channel.epoll.EpollEventLoop.run(EpollEventLoop.java:378) ~[netty-transport-native-epoll-4.1.58.Final-linux-x86_64.jar:4.1.58.Final]
                at io.netty.util.concurrent.SingleThreadEventExecutor$4.run(SingleThreadEventExecutor.java:989) ~[netty-common-4.1.58.Final.jar:4.1.58.Final]
                at io.netty.util.internal.ThreadExecutorMap$2.run(ThreadExecutorMap.java:74) ~[netty-common-4.1.58.Final.jar:4.1.58.Final]
                at io.netty.util.concurrent.FastThreadLocalRunnable.run(FastThreadLocalRunnable.java:30) ~[netty-common-4.1.58.Final.jar:4.1.58.Final]
                at java.base/java.lang.Thread.run(Unknown Source) ~[na:na]

My question is how can I make spring cloud gateway to route to a service which is in another namespace?

Upvotes: 0

Views: 2063

Answers (1)

Er. Daksh soni
Er. Daksh soni

Reputation: 1

Try with the below changes.

  • No need to enable gateway discovery if you are defining routes.

  • Also make changes in filter regex use as below.

RewritePath=/my-custom-url(? < segment >.*), /$\ {segment}

  • If it's not work then please change the route url like as below.

http://<ip_address>:<port_no.>/my-custom-url/**

Upvotes: 0

Related Questions