This version is still in development and is not considered stable yet. For the latest stable version, please use Spring Cloud Gateway 4.2.0!

`SetRequestHeader` Filter

The SetRequestHeader filter takes name and value parameters. The following listing configures a SetRequestHeader filter:

application.yml

spring:
  cloud:
    gateway:
      mvc:
        routes:
        - id: setrequestheader_route
          uri: https://example.org
          filters:
          - SetRequestHeader=X-Request-Red, Blue

GatewaySampleApplication.java

import static org.springframework.cloud.gateway.server.mvc.filter.BeforeFilterFunctions.setRequestHostHeader;
import static org.springframework.cloud.gateway.server.mvc.handler.GatewayRouterFunctions.route;
import static org.springframework.cloud.gateway.server.mvc.handler.HandlerFunctions.http;

@Configuration
class RouteConfiguration {

    @Bean
    public RouterFunction<ServerResponse> gatewayRouterFunctionsSetRequestHeader() {
		return route("add_request_parameter_route")
				.GET("/**", http("https://example.org"))
					.before(setRequestHostHeader("X-Request-Red", "Blue"))
					.build();
    }
}

This filter replaces (rather than adding) all headers with the given name. So, if the downstream server responded with X-Request-Red:1234, it will be replaced with X-Request-Red:Blue, which is what the downstream service would receive.

SetRequestHeader is aware of URI variables used to match a path or host. URI variables may be used in the value and are expanded at runtime. The following example configures an SetRequestHeader filter that uses a variable:

application.yml

spring:
  cloud:
    gateway:
      routes:
      - id: setrequestheader_route
        uri: https://example.org
        predicates:
        - Host: {segment}.myhost.org
        filters:
        - SetRequestHeader=X-Request-Red, Blue-{segment}

GatewaySampleApplication.java

import static org.springframework.cloud.gateway.server.mvc.filter.BeforeFilterFunctions.setRequestHostHeader;
import static org.springframework.cloud.gateway.server.mvc.handler.GatewayRouterFunctions.route;
import static org.springframework.cloud.gateway.server.mvc.handler.HandlerFunctions.http;
import static import static org.springframework.cloud.gateway.server.mvc.predicate.GatewayRequestPredicates.host;

@Configuration
class RouteConfiguration {

    @Bean
    public RouterFunction<ServerResponse> gatewayRouterFunctionsSetRequestHeader() {
		return route("add_request_parameter_route")
				.route(host("{segment}.myhost.org"), http("https://example.org"))
					.before(setRequestHostHeader("X-Request-Red", "Blue-{segment}"))
					.build();
    }
}

SetRequestHeader Filter

`SetRequestHeader` Filter