Filtros globales y GatewayFilterFactory
Comprenda el concepto de los filtros globales y aprenda a utilizar GatewayFilterFactories integradas para realizar transformaciones habituales.
Filtros globales y GatewayFilterFactory es una lección gratuita de API Gateway & Reverse Proxy (Nginx + Spring Cloud Gateway) en CoddyKit. Esta es la lección 1 de 4. Puedes leer la lección completa abajo gratuitamente — luego la practicas en el navegador con un editor de código integrado y un tutor de IA 24/7. Forma parte de la ruta de aprendizaje de API Gateway & Reverse Proxy (Nginx + Spring Cloud Gateway), y tu progreso se sincroniza en la web y la app de CoddyKit. El curso de API Gateway & Reverse Proxy (Nginx + Spring Cloud Gateway) incluye 4 lecciones en total.
Partes de esta lección aún no han sido traducidas y se muestran en inglés.
What are Gateway Filters?
In Spring Cloud Gateway, filters are like interceptors that allow you to modify incoming HTTP requests or outgoing HTTP responses.
They provide a powerful way to implement cross-cutting concerns for your API traffic, such as security, logging, or data transformation.
Pre- and Post-Filters
Spring Cloud Gateway supports two main types of filter execution:
- Pre-filters: Executed before the request is sent to the downstream service. Great for authentication, logging, or modifying request headers.
- Post-filters: Executed after the response is received from the downstream service but before it's sent back to the client. Useful for modifying responses, caching, or error handling.
Understanding Global Filters
A Global Filter is applied to every single request that passes through the gateway, regardless of the specific route it matches.
This makes them ideal for concerns that affect all your API traffic, like global logging, security checks, or metrics collection across all services.
They implement the GlobalFilter interface.
Building a Custom Global Filter
Let's create a simple global filter that logs the incoming request path. It needs to implement GlobalFilter and Ordered.
Run this Spring Boot app and access http://localhost:8080/test/hello. You'll see the log in the console!
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.gateway.filter.GlobalFilter;
import org.springframework.cloud.gateway.filter.GatewayFilterChain;
import org.springframework.cloud.gateway.route.RouteLocator;
import org.springframework.cloud.gateway.route.builder.RouteLocatorBuilder;
import org.springframework.context.annotation.Bean;
import org.springframework.core.Ordered;
import org.springframework.stereotype.Component;
import org.springframework.web.server.ServerWebExchange;
import reactor.core.publisher.Mono;
@SpringBootApplication
public class GatewayApp {
public static void main(String[] args) {
SpringApplication.run(GatewayApp.class, args);
}
// A simple route for demonstration
@Bean
public RouteLocator customRouteLocator(RouteLocatorBuilder builder) {
return builder.routes()
.route("test_route", r -> r.path("/test/**")
.uri("http://httpbin.org:80")) // Public test service
.build();
}
@Component
static class MyLoggingFilter implements GlobalFilter, Ordered {
@Override
public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {
System.out.println("Global Filter: Request Path -> " + exchange.getRequest().getPath());
return chain.filter(exchange); // Continue filter chain
}
@Override
public int getOrder() {
return -1; // Execute very early
}
}
}Understanding Filter Order
When multiple filters (global or route-specific) are present, their execution order matters.
Filters that implement the Ordered interface define their priority using the getOrder() method. Lower values mean higher priority (executed earlier).
- Negative values: Very high priority.
- Positive values: Lower priority.
- Filters without an explicit order often run later.
What is a GatewayFilterFactory?
While GlobalFilters apply everywhere, a GatewayFilterFactory provides reusable, configurable filters that you can apply to specific routes.
Spring Cloud Gateway comes with many built-in factories for common tasks, like adding/removing headers, rewriting paths, or applying rate limits. You configure them per route.
AddRequestHeader Factory in Action
The AddRequestHeader factory adds a static header to the request before it's forwarded to the backend service.
Run this example and navigate to http://localhost:8080/add-header/test. The response from httpbin.org will show the added header!
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.gateway.route.RouteLocator;
import org.springframework.cloud.gateway.route.builder.RouteLocatorBuilder;
import org.springframework.context.annotation.Bean;
@SpringBootApplication
public class GatewayApp {
public static void main(String[] args) {
SpringApplication.run(GatewayApp.class, args);
}
@Bean
public RouteLocator customRouteLocator(RouteLocatorBuilder builder) {
return builder.routes()
.route("add_header_route", r -> r.path("/add-header/**")
.filters(f -> f.addRequestHeader("X-Gateway-Custom", "CoddyKit"))
.uri("http://httpbin.org:80/headers")) // Shows request headers
.build();
}
}Exploring More Built-in Factories
Spring Cloud Gateway offers many other powerful GatewayFilterFactory implementations:
RemoveRequestHeader: Removes a specified header.RewritePath: Changes the request URI path.Retry: Retries failed requests.RateLimiter: Applies rate limiting to requests.
These factories simplify common gateway tasks without writing custom code.
Global vs. Route-Specific Filters
When should you use a Global Filter versus a GatewayFilterFactory?
- Choose Global Filters for: Cross-cutting concerns affecting all requests (e.g., global security, logging).
- Choose
GatewayFilterFactory(route-specific) for: Logic specific to certain APIs or groups of routes (e.g., API versioning, specific header manipulation, rate limiting on a particular endpoint).
Global Filter Check
Consider a Spring Cloud Gateway application. Which statement is TRUE about Global Filters?
Global Filters & Factories Recap
We've explored Global Filters, which apply to all requests, and learned how to create a custom one. We also introduced GatewayFilterFactory, which offers reusable, configurable filters for specific routes.
Understanding these filter types and when to use them is crucial for building powerful and flexible API Gateways with Spring Cloud Gateway.
Preguntas frecuentes
¿La lección «Filtros globales y GatewayFilterFactory» es gratis?
Sí — el texto completo de «Filtros globales y GatewayFilterFactory» es gratis para leer aquí en la web. Para practicarla de forma interactiva (editor de código integrado y tutor de IA 24/7) y desbloquear el resto del curso de API Gateway & Reverse Proxy (Nginx + Spring Cloud Gateway), actualiza a CoddyKit PRO. El curso de API Gateway & Reverse Proxy (Nginx + Spring Cloud Gateway) incluye 4 lecciones en total.
¿Qué aprenderé en «Filtros globales y GatewayFilterFactory»?
Comprenda el concepto de los filtros globales y aprenda a utilizar GatewayFilterFactories integradas para realizar transformaciones habituales. Practicas API Gateway & Reverse Proxy (Nginx + Spring Cloud Gateway) con código real que ejecutas directamente en el navegador, y un tutor de IA 24/7 responde tus preguntas mientras trabajas en la lección.
¿Necesito experiencia previa para empezar API Gateway & Reverse Proxy (Nginx + Spring Cloud Gateway)?
No se requiere experiencia previa. API Gateway & Reverse Proxy (Nginx + Spring Cloud Gateway) en CoddyKit está estructurado para principiantes hasta estudiantes avanzados, así que puedes empezar aquí o desde el inicio y avanzar a tu ritmo. Esta es la lección 1 de 4.
¿Cuánto tiempo toma la lección «Filtros globales y GatewayFilterFactory»?
La mayoría de las lecciones de CoddyKit toman alrededor de 5–10 minutos. Cada una es compacta e interactiva, así que avanzas constantemente y retomas exactamente por donde dejaste en la web y la app.
¿Puedo escribir y ejecutar código en esta lección de API Gateway & Reverse Proxy (Nginx + Spring Cloud Gateway)?
Sí. Cada lección de API Gateway & Reverse Proxy (Nginx + Spring Cloud Gateway) incluye un editor de código integrado, así que escribes y ejecutas código real directamente en tu navegador y obtienes retroalimentación instantánea de IA — sin configuración local necesaria.
Todas las lecciones de este curso
- Filtros globales y GatewayFilterFactory
- Filtros personalizados de solicitudes y respuestas
- Procesamiento previo y posterior con filtros
- GatewayFilters integrados que debe conocer