`RequestSize` Filter

When the request size is greater than the permissible limit, the RequestSize filter can restrict a request from reaching the downstream service. The filter takes a maxSize parameter. The maxSize is a DataSize type, so values can be defined as a number followed by an optional DataUnit suffix such as 'KB' or 'MB'. The default is 'B' for bytes. It is the permissible size limit of the request defined in bytes. The following listing configures a RequestSize filter:

application.yml

spring:
  cloud:
    gateway:
      mvc:
        routes:
        - id: request_size_route
          uri: http://localhost:8080
          predicates:
          - Path=/upload
          filters:
          - name: RequestSize
            args:
              maxSize: 5000000

GatewaySampleApplication.java

import static org.springframework.cloud.gateway.server.mvc.filter.BeforeFilterFunctions.requestSize;
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> gatewayRouterFunctionsRequestSize() {
		return route("request_size_route")
				.GET("/upload", http("http://localhost:8080"))
					.before(requestSize("5000000"))
					.build();
    }
}

The RequestSize filter sets the response status as 413 Payload Too Large with an additional header errorMessage when the request is rejected due to size. The following example shows such an errorMessage:

errorMessage : Request size is larger than permissible limit. Request size is 6.0 MB where permissible limit is 5.0 MB

The default request size is set to five MB if not provided as a filter argument in the route definition.

RequestSize Filter

`RequestSize` Filter