This version is still in development and is not considered stable yet. For the latest stable version, please use Spring Cloud Gateway 4.1.5!

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();
    }
}