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!

`MapRequestHeader` Filter

The MapRequestHeader filter takes fromHeader and toHeader parameters. It creates a new named header (toHeader), and the value is extracted out of an existing named header (fromHeader) from the incoming http request. If the input header does not exist, the filter has no impact. If the new named header already exists, its values are augmented with the new values. The following example configures a MapRequestHeader:

application.yml

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

GatewaySampleApplication.java

import static org.springframework.cloud.gateway.server.mvc.filter.BeforeFilterFunctions.addRequestParameter;
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> gatewayRouterFunctionsMapRequestHeader() {
        return route("map_request_header_route")
				.GET("/mypath", http("https://example.org"))
				.before(mapRequestHeader("Blue", "X-Request-Red"))
				.build();
    }
}

This adds the X-Request-Red:<values> header to the downstream request with updated values from the incoming HTTP request’s Blue header.

MapRequestHeader Filter

`MapRequestHeader` Filter