Spring Cloud Gateway - Proxy/Forward the entire sub part of URL

Shervin Asgari picture Shervin Asgari · Feb 19, 2018 · Viewed 20.3k times · Source

I am using Spring Cloud Gateway 2.0.0.M6 testing a simple gateway. I just want a URL to be forwarded to another URL with ** regex

Example 1: /integration/sbl/foo/bar => localhost:4178/a-integration/sbl/foo/bar

Example 2: /integration/sbl/baz/bad => localhost:4178/a-integration/sbl/baz/bad

So far I have written the following, but it only forwards to http://localhost:4178/a-integration/

 @Bean
public RouteLocator routeLocator(RouteLocatorBuilder builder) {
    String test = "http://localhost:4178/a-integration/";

    return builder.routes()
            .route("integration-test",
                    r -> r.path("/integration/sbl/**")
                            .uri(test)
            )
            .build();
}

How can I fix the above code to enable this behaviour?

EDIT

I tried the following based on response below

String samtykke = "http://localhost:4178/";

return builder.routes()

        .route("samtykke", r -> r
                .path("/gb-integration/sbl/**")
                .filters(f -> f.rewritePath("/gb-integration/sbl/(?<segment>.*)", "/gb-samtykke-integration/${segment}"))
                .uri(samtykke))
        .build();

and I tried a GET http://localhost:4177/gb-integration/sbl/api/sbl/income/ and expected http://localhost:4178/gb-samtykke-integration/api/sbl/income/ back but it didn't work.

The output says:

2018-02-23 09:46:35.197 TRACE 6364 --- [ctor-http-nio-2] o.s.c.g.h.p.RoutePredicateFactory        : Pattern "/gb-integration/sbl/**" matches against value "[path='/gb-integration/sbl/api/sbl/income/']"
2018-02-23 09:46:35.198 DEBUG 6364 --- [ctor-http-nio-2] o.s.c.g.h.RoutePredicateHandlerMapping   : Route matched: samtykke
2018-02-23 09:46:35.198 DEBUG 6364 --- [ctor-http-nio-2] o.s.c.g.h.RoutePredicateHandlerMapping   : Mapping [Exchange: GET http://localhost:4177/gb-integration/sbl/api/sbl/income/] to Route{id='samtykke', uri=http://localhost:4178/, order=0, predicate=org.springframework.cloud.gateway.handler.predicate.PathRoutePredicateFactory$$Lambda$245/1803714790@1d0042df, gatewayFilters=[OrderedGatewayFilter{delegate=org.springframework.cloud.gateway.filter.factory.RewritePathGatewayFilterFactory$$Lambda$247/485237151@77da026a, order=0}]}
2018-02-23 09:46:35.200 DEBUG 6364 --- [ctor-http-nio-2] o.s.c.g.handler.FilteringWebHandler      : Sorted gatewayFilterFactories: [OrderedGatewayFilter{delegate=GatewayFilterAdapter{delegate=org.springframework.cloud.gateway.filter.NettyWriteResponseFilter@5c534b5b}, order=-1}, OrderedGatewayFilter{delegate=org.springframework.cloud.gateway.filter.factory.RewritePathGatewayFilterFactory$$Lambda$247/485237151@77da026a, order=0}, OrderedGatewayFilter{delegate=GatewayFilterAdapter{delegate=org.springframework.cloud.gateway.filter.RouteToRequestUrlFilter@396639b}, order=10000}, OrderedGatewayFilter{delegate=GatewayFilterAdapter{delegate=org.springframework.cloud.gateway.filter.NettyRoutingFilter@a18649a}, order=2147483647}, OrderedGatewayFilter{delegate=GatewayFilterAdapter{delegate=org.springframework.cloud.gateway.filter.ForwardRoutingFilter@2b22a1cc}, order=2147483647}, OrderedGatewayFilter{delegate=GatewayFilterAdapter{delegate=org.springframework.cloud.gateway.filter.WebsocketRoutingFilter@62573c86}, order=2147483647}]
2018-02-23 09:46:35.232 TRACE 6364 --- [ctor-http-nio-2] o.s.c.g.filter.RouteToRequestUrlFilter   : RouteToRequestUrlFilter start
2018-02-23 09:46:35.314 TRACE 6364 --- [ctor-http-nio-1] o.s.c.g.filter.NettyWriteResponseFilter  : NettyWriteResponseFilter start

Answer

Boyen picture Boyen · Feb 21, 2018

You can use the rewritePath functionality in your path filters, as specified by the documentation found here :

https://cloud.spring.io/spring-cloud-gateway/reference/html/#rewritepath-gatewayfilter-factory

Relevant parts :

5.12 RewritePath GatewayFilter Factory

The RewritePath GatewayFilter Factory takes a path regexp parameter and a replacement parameter. This uses Java regular expressions for a flexible way to rewrite the request path.

spring:   
  cloud:
     gateway:
       routes:
       - id: rewritepath_route
         uri: http://example.org
         predicates:
         - Path=/foo/**
         filters:
         - RewritePath=/foo/(?<segment>.*), /$\{segment}

For a request path of /foo/bar, this will set the path to /bar before making the downstream request. Notice the $\ which is replaced with $ because of the YAML spec.

In your example, that would look like :

@Bean
public RouteLocator routeLocator(RouteLocatorBuilder builder) {
    String test = "http://localhost:4178";

    return builder.routes()
            .route("integration-test", r -> r
                    .path("/integration/sbl/**")
                    .filters(f->f.rewritePath("/integration/(?<segment>.*)","/a-integration/${segment}"))
                    .uri(test)
                  )
            .build();
}