SpringCloud：使用SpringCloud Gateway过程中一些问题的说明

朴灿烈づ我的快乐病毒、 2022-11-15 14:18 557阅读 0赞

**目录**

一、SpringCloud Gateway如何单独使用而不集成注册中心

二、如何查看使用的路由规则（route）和过滤器（filter）

三、过滤器（filter）的执行顺序是怎样的

四、filter定制时pre阶段、post阶段各有几种实现方式

五、如何中止filter调用链

六、调用超时后是如何处理

--------------------

# 一、SpringCloud Gateway如何单独使用而不集成注册中心 #

1.由于不需要引入注册中心，所以pom.xml只需要如下依赖

<dependency>
    	<groupId>org.springframework.boot</groupId>
    	<artifactId>spring-boot-starter-webflux</artifactId>
    	<version>2.4.4</version>
    </dependency>
    <dependency>
    	<groupId>org.springframework.cloud</groupId>
    	<artifactId>spring-cloud-starter-gateway</artifactId>
    	<version>3.0.2</version>
    </dependency>

2.java代码中使用@SpringBootApplication，不要使用@SpringCloudApplication

import org.springframework.boot.SpringApplication;
    import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
    import org.springframework.boot.autoconfigure.SpringBootApplication;
    import org.springframework.boot.autoconfigure.web.servlet.error.ErrorMvcAutoConfiguration;
    import org.springframework.context.annotation.Configuration;
    
    @Configuration
    @SpringBootApplication
    @EnableAutoConfiguration(exclude = { ErrorMvcAutoConfiguration.class })
    public class SpringCloudGatewayApplication {
    
    	public static void main(String[] args) {
    		SpringApplication.run(SpringCloudGatewayApplication.class, args);
    	}
    
    }

如果使用@SpringCloudApplication，在低版本的SpringCloud中可能会报错

# 二、如何查看使用的路由规则（route）和过滤器（filter） #

1.pom.xml中添加actuator

<dependency>
    	<groupId>org.springframework.boot</groupId>
    	<artifactId>spring-boot-starter-actuator</artifactId>
    	<version>2.4.4</version>
    </dependency>

2.在application.properties文件中开放管理端口

> management.endpoint.gateway.enabled=true  
> management.endpoints.web.exposure.include=gateway

3.查看所有全局filter  
/actuator/gateway/globalfilters

> \{  
> "org.springframework.cloud.gateway.filter.GatewayMetricsFilter@65b66b08":0,  
> "org.springframework.cloud.gateway.filter.NettyRoutingFilter@27a97e08":2147483647,  
> "org.springframework.cloud.gateway.filter.NettyWriteResponseFilter@77e7246b":-1,  
> "org.springframework.cloud.gateway.config.GatewayNoLoadBalancerClientAutoConfiguration$NoLoadBalancerClientFilter@4726927c":10150,  
> "org.springframework.cloud.gateway.filter.WebsocketRoutingFilter@5017e1":2147483646,  
> "org.springframework.cloud.gateway.filter.ForwardPathFilter@1f44ddab":0,  
> "org.springframework.cloud.gateway.filter.AdaptCachedBodyGlobalFilter@18eec010":-2147482648,  
> "org.springframework.cloud.gateway.filter.ForwardRoutingFilter@51ce6f85":2147483647,  
> "org.springframework.cloud.gateway.filter.RemoveCachedBodyFilter@5918c260":-2147483648,  
> "org.springframework.cloud.gateway.filter.RouteToRequestUrlFilter@3d7b1f1c":10000  
> \}

4.查看所有可在route中使用的filter  
/actuator/gateway/routefilters

> \{  
> "\[SetResponseHeaderGatewayFilterFactory@7487b142 configClass = AbstractNameValueGatewayFilterFactory.NameValueConfig\]":null,  
> "\[PreserveHostHeaderGatewayFilterFactory@13da7ab0 configClass = Object\]":null,  
> "\[RemoveRequestParameterGatewayFilterFactory@3724b43e configClass = AbstractGatewayFilterFactory.NameConfig\]":null,  
> "\[RewriteLocationResponseHeaderGatewayFilterFactory@199bc830 configClass = RewriteLocationResponseHeaderGatewayFilterFactory.Config\]":null,  
> "\[RemoveResponseHeaderGatewayFilterFactory@77eb5790 configClass = AbstractGatewayFilterFactory.NameConfig\]":null,  
> "\[AddRequestParameterGatewayFilterFactory@602ae7b6 configClass = AbstractNameValueGatewayFilterFactory.NameValueConfig\]":null,  
> "\[ModifyResponseBodyGatewayFilterFactory@700f518a configClass = ModifyResponseBodyGatewayFilterFactory.Config\]":null,  
> "\[ModifyRequestBodyGatewayFilterFactory@71ad3d8a configClass = ModifyRequestBodyGatewayFilterFactory.Config\]":null,  
> "\[DedupeResponseHeaderGatewayFilterFactory@47af099e configClass = DedupeResponseHeaderGatewayFilterFactory.Config\]":null,  
> "\[SetRequestHostHeaderGatewayFilterFactory@81b5db0 configClass = SetRequestHostHeaderGatewayFilterFactory.Config\]":null,  
> "\[PrefixPathGatewayFilterFactory@b835727 configClass = PrefixPathGatewayFilterFactory.Config\]":null,  
> "\[RewritePathGatewayFilterFactory@68e7c8c3 configClass = RewritePathGatewayFilterFactory.Config\]":null,  
> "\[StripPrefixGatewayFilterFactory@3e17a0a1 configClass = StripPrefixGatewayFilterFactory.Config\]":null,  
> "\[RewriteResponseHeaderGatewayFilterFactory@7139bd31 configClass = RewriteResponseHeaderGatewayFilterFactory.Config\]":null,  
> "\[RequestHeaderSizeGatewayFilterFactory@150ede8b configClass = RequestHeaderSizeGatewayFilterFactory.Config\]":null,  
> "\[RequestHeaderToRequestUriGatewayFilterFactory@790a251b configClass = AbstractGatewayFilterFactory.NameConfig\]":null,  
> "\[MapRequestHeaderGatewayFilterFactory@3901f6af configClass = MapRequestHeaderGatewayFilterFactory.Config\]":null,  
> "\[RemoveRequestHeaderGatewayFilterFactory@260ff5b7 configClass = AbstractGatewayFilterFactory.NameConfig\]":null,  
> "\[AddResponseHeaderGatewayFilterFactory@10cd6753 configClass = AbstractNameValueGatewayFilterFactory.NameValueConfig\]":null,  
> "\[RetryGatewayFilterFactory@319c3a25 configClass = RetryGatewayFilterFactory.RetryConfig\]":null,  
> "\[SecureHeadersGatewayFilterFactory@ef1695a configClass = SecureHeadersGatewayFilterFactory.Config\]":null,  
> "\[SetRequestHeaderGatewayFilterFactory@58860997 configClass = AbstractNameValueGatewayFilterFactory.NameValueConfig\]":null,  
> "\[SaveSessionGatewayFilterFactory@27b45ea configClass = Object\]":null,  
> "\[RequestSizeGatewayFilterFactory@4d8286c4 configClass = RequestSizeGatewayFilterFactory.RequestSizeConfig\]":null,  
> "\[AddRequestHeaderGatewayFilterFactory@d8d9199 configClass = AbstractNameValueGatewayFilterFactory.NameValueConfig\]":null,  
> "\[SetStatusGatewayFilterFactory@4b3fe06e configClass = SetStatusGatewayFilterFactory.Config\]":null,  
> "\[RedirectToGatewayFilterFactory@2c8662ac configClass = RedirectToGatewayFilterFactory.Config\]":null,  
> "\[SetPathGatewayFilterFactory@238bfd6c configClass = SetPathGatewayFilterFactory.Config\]":null  
> \}

5.查看自定义的route规则，其中包括在这条路由规则中使用的filter  
/actuator/gateway/routes

> \[\{  
>     "predicate":"Paths: \[/\*\*\], match trailing slash: true",  
>     "route\_id":"d98947ea-2593-4a80-898a-73028b6e1321",  
>     "filters":\["com.tech.gw.CustomerFilter@70e44883"\],  
>     "uri":"no://op",  
>     "order":0  
> \}\]

规则最终使用的所有filter，是route规则中使用的filter+全局filter的合集

# 三、过滤器（filter）的执行顺序是怎样的 #

SpringCloud Gateway中的filter是使用order定义优先级的，值越小优先级越高，pre阶段执行越靠前，post阶段执行越靠后。

以下只列出了GlobalFilter的执行顺序：

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L25ldHllYXhp_size_16_color_FFFFFF_t_70][]

规则如下：

1.全局filter都已定义了order的值，由order值决定优先级。如果order值相同，则先注册的优先级高

2.route规则中添加的filter需要指定order的值，如果不指定，则默认值为0。如果有多个filter的order值相同，则按它们在路由中的添加顺序来决定优先级，先添加的优先级高

@Bean
    public RouteLocator myRoutes(RouteLocatorBuilder builder) {
    	return builder.routes().route(p -> p.path("/**").filters(f -> f.filter(filter1).filter(filter2).filter(filter)).uri("no://op")).build();
    }

优先级：filter1 > filter2 > filter

3.在执行过程中，是会将全局filter和route规则定义的filter一起按order排优先级的。如果全局filter与route规则定义的filter的order值一样，则全局filter优先级高

# 四、filter定制时pre阶段、post阶段各有几种实现方式 #

通过以下样例进行展示

import org.springframework.cloud.gateway.filter.GatewayFilter;
    import org.springframework.cloud.gateway.filter.GatewayFilterChain;
    import org.springframework.stereotype.Component;
    import org.springframework.web.server.ServerWebExchange;
    
    import reactor.core.publisher.Mono;
    
    @Component
    public class GatewayFilter1 implements GatewayFilter {
    
    	@Override
    	public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {
    
    		Mono<Void> mono1 = Mono.fromRunnable(() -> {
    			System.out.println("GatewayFilter1:before chain.filter in mono"); // 1
    		});
    		Mono<Void> mono2 = Mono.fromRunnable(() -> {
    			System.out.println("GatewayFilter1:after  chain.filter in mono"); // 2
    		});
    		
    		System.out.println("GatewayFilter1:before chain.filter"); // 3
    
    		Mono<Void> retMono = mono1.then(chain.filter(exchange)).then(mono2);
    		
    		System.out.println("GatewayFilter1:after  chain.filter"); // 4
    
    		return retMono;
    	}
    }

import org.springframework.cloud.gateway.filter.GatewayFilter;
    import org.springframework.cloud.gateway.filter.GatewayFilterChain;
    import org.springframework.stereotype.Component;
    import org.springframework.web.server.ServerWebExchange;
    
    import reactor.core.publisher.Mono;
    
    @Component
    public class GatewayFilter2 implements GatewayFilter {
    
    	@Override
    	public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {
    
    		Mono<Void> mono1 = Mono.fromRunnable(() -> {
    			System.out.println("GatewayFilter2:before chain.filter in mono"); // 1
    		});
    		Mono<Void> mono2 = Mono.fromRunnable(() -> {
    			System.out.println("GatewayFilter2:after  chain.filter in mono"); // 2
    		});
    
    		System.out.println("GatewayFilter2:before chain.filter"); // 3
    
    		Mono<Void> retMono = mono1.then(chain.filter(exchange)).then(mono2);
    
    		System.out.println("GatewayFilter2:after  chain.filter"); // 4
    
    		return retMono;
    	}
    }

import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.boot.SpringApplication;
    import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
    import org.springframework.boot.autoconfigure.SpringBootApplication;
    import org.springframework.boot.autoconfigure.web.servlet.error.ErrorMvcAutoConfiguration;
    import org.springframework.cloud.gateway.route.RouteLocator;
    import org.springframework.cloud.gateway.route.builder.RouteLocatorBuilder;
    import org.springframework.context.annotation.Bean;
    import org.springframework.context.annotation.Configuration;
    
    @Configuration
    @SpringBootApplication
    @EnableAutoConfiguration(exclude = { ErrorMvcAutoConfiguration.class })
    public class SpringCloudGatewayApplication {
    
    	public static void main(String[] args) {
    		SpringApplication.run(SpringCloudGatewayApplication.class, args);
    	}
    
    	@Autowired
    	private GatewayFilter1 filter1;
    
    	@Autowired
    	private GatewayFilter2 filter2;
    
    	@Bean
    	public RouteLocator myRoutes(RouteLocatorBuilder builder) {
    		return builder.routes().route(p -> p.path("/**").filters(f -> f.filter(filter1).filter(filter2)).uri("no://op"))
    				.build();
    	}
    }

执行结果：

> GatewayFilter1:before chain.filter  
> GatewayFilter1:after  chain.filter  
> GatewayFilter1:before chain.filter in mono  
> GatewayFilter2:before chain.filter  
> GatewayFilter2:after  chain.filter  
> GatewayFilter2:before chain.filter in mono  
> GatewayFilter2:after  chain.filter in mono  
> GatewayFilter1:after  chain.filter in mono

从结果中可以看出，在pre阶段执行可以在1、2、3处理添加代码；而在post阶段执行则可在4处添加代码。

再看一下更复杂的例子

import org.reactivestreams.Publisher;
    import org.springframework.cloud.gateway.filter.GatewayFilter;
    import org.springframework.cloud.gateway.filter.GatewayFilterChain;
    import org.springframework.core.io.buffer.DataBuffer;
    import org.springframework.http.server.reactive.ServerHttpRequestDecorator;
    import org.springframework.http.server.reactive.ServerHttpResponseDecorator;
    import org.springframework.stereotype.Component;
    import org.springframework.web.server.ServerWebExchange;
    
    import reactor.core.publisher.Flux;
    import reactor.core.publisher.Mono;
    
    @Component
    public class GatewayFilter1 implements GatewayFilter {
    
    	@Override
    	public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {
    
    		ServerHttpRequestDecorator request = new ServerHttpRequestDecorator(exchange.getRequest()) {
    
    			@Override
    			public Flux<DataBuffer> getBody() {
    				System.out.println(Thread.currentThread() + ":GatewayFilter1:in chain.request"); // 1
    
    				return super.getBody().map(dataBuffer -> {
    					System.out.println(Thread.currentThread() + ":GatewayFilter1:in chain.request map"); // 2
    
    					return dataBuffer;
    				});
    			}
    		};
    
    		ServerHttpResponseDecorator response = new ServerHttpResponseDecorator(exchange.getResponse()) {
    
    			@Override
    			public Mono<Void> writeWith(Publisher<? extends DataBuffer> body) {
    				System.out.println(Thread.currentThread() + ":GatewayFilter1:in chain.response"); // 3
    
    				Flux<DataBuffer> bodyFlux = Flux.from(body);
    
    				bodyFlux = bodyFlux.map(dataBuffer -> {
    					System.out.println(Thread.currentThread() + ":GatewayFilter1:in chain.response map"); // 4
    
    					return dataBuffer;
    				});
    
    				return super.writeWith(bodyFlux);
    			}
    
    			@Override
    			public Mono<Void> writeAndFlushWith(Publisher<? extends Publisher<? extends DataBuffer>> body) {
    				System.out.println(Thread.currentThread() + ":ModifiedServerHttpResponse2");
    				return writeWith(Flux.from(body).flatMapSequential(p -> p));
    			}
    		};
    
    		Mono<Void> mono1 = Mono.fromRunnable(() -> {
    			System.out.println(Thread.currentThread() + ":GatewayFilter1:before chain.filter in mono"); // 5
    		});
    		Mono<Void> mono2 = Mono.fromRunnable(() -> {
    			System.out.println(Thread.currentThread() + ":GatewayFilter1:after  chain.filter in mono"); // 6
    		});
    
    		System.out.println(Thread.currentThread() + ":GatewayFilter1:before chain.filter"); // 7
    
    		Mono<Void> retMono = mono1.then(chain.filter(exchange.mutate().request(request).response(response).build()))
    				.then(mono2);
    
    		System.out.println(Thread.currentThread() + ":GatewayFilter1:after  chain.filter"); // 8
    
    		return retMono;
    	}
    
    }

import org.reactivestreams.Publisher;
    import org.springframework.cloud.gateway.filter.GatewayFilter;
    import org.springframework.cloud.gateway.filter.GatewayFilterChain;
    import org.springframework.core.io.buffer.DataBuffer;
    import org.springframework.http.server.reactive.ServerHttpRequestDecorator;
    import org.springframework.http.server.reactive.ServerHttpResponseDecorator;
    import org.springframework.stereotype.Component;
    import org.springframework.web.server.ServerWebExchange;
    
    import reactor.core.publisher.Flux;
    import reactor.core.publisher.Mono;
    
    @Component
    public class GatewayFilter2 implements GatewayFilter {
    
    	@Override
    	public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {
    
    		ServerHttpRequestDecorator request = new ServerHttpRequestDecorator(exchange.getRequest()) {
    
    			@Override
    			public Flux<DataBuffer> getBody() {
    				System.out.println(Thread.currentThread() + ":GatewayFilter2:in chain.request"); // 1
    
    				return super.getBody().map(dataBuffer -> {
    					System.out.println(Thread.currentThread() + ":GatewayFilter2:in chain.request map"); // 2
    
    					return dataBuffer;
    				});
    			}
    		};
    
    		ServerHttpResponseDecorator response = new ServerHttpResponseDecorator(exchange.getResponse()) {
    
    			@Override
    			public Mono<Void> writeWith(Publisher<? extends DataBuffer> body) {
    				System.out.println(Thread.currentThread() + ":GatewayFilter2:in chain.response"); // 3
    
    				Flux<DataBuffer> bodyFlux = Flux.from(body);
    
    				bodyFlux = bodyFlux.map(dataBuffer -> {
    					System.out.println(Thread.currentThread() + ":GatewayFilter2:in chain.response map"); // 4
    
    					return dataBuffer;
    				});
    
    				return super.writeWith(bodyFlux);
    			}
    			
    			@Override
    			public Mono<Void> writeAndFlushWith(Publisher<? extends Publisher<? extends DataBuffer>> body) {
    				return writeWith(Flux.from(body).flatMapSequential(p -> p));
    			}
    		};
    
    		Mono<Void> mono1 = Mono.fromRunnable(() -> {
    			System.out.println(Thread.currentThread() + ":GatewayFilter2:before chain.filter in mono"); // 5
    		});
    		Mono<Void> mono2 = Mono.fromRunnable(() -> {
    			System.out.println(Thread.currentThread() + ":GatewayFilter2:after  chain.filter in mono"); // 6
    		});
    
    		System.out.println(Thread.currentThread() + ":GatewayFilter2:before chain.filter"); // 7
    
    		Mono<Void> retMono = mono1.then(chain.filter(exchange.mutate().request(request).response(response).build()))
    				.then(mono2);
    
    		System.out.println(Thread.currentThread() + ":GatewayFilter2:after  chain.filter"); // 8
    
    		return retMono;
    	}
    }

import java.net.URI;
    import java.net.URISyntaxException;
    import java.util.List;
    
    import org.springframework.cloud.gateway.filter.GatewayFilter;
    import org.springframework.cloud.gateway.filter.GatewayFilterChain;
    import org.springframework.cloud.gateway.filter.RouteToRequestUrlFilter;
    import org.springframework.cloud.gateway.support.ServerWebExchangeUtils;
    import org.springframework.core.Ordered;
    import org.springframework.stereotype.Component;
    import org.springframework.web.server.ServerWebExchange;
    
    import reactor.core.publisher.Mono;
    
    @Component
    public class CustomFilter implements GatewayFilter, Ordered {
    
    	@Override
    	public int getOrder() {
    		return RouteToRequestUrlFilter.ROUTE_TO_URL_FILTER_ORDER + 1;
    	}
    
    	@Override
    	public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {
    		try {
    			exchange.getAttributes().put(ServerWebExchangeUtils.GATEWAY_REQUEST_URL_ATTR, new URI("http://127.0.0.1:9090/TestWebApp/testServlet"));
    		} catch (URISyntaxException e) {
    			e.printStackTrace();
    		}
    
    		Mono<Void> mono1 = Mono
    				.fromRunnable(() -> System.out.println(Thread.currentThread() + ":CustomerFilter:before"));
    		Mono<Void> mono2 = Mono
    				.fromRunnable(() -> System.out.println(Thread.currentThread() + ":CustomerFilter:after"));
    
    		Mono<Void> ret = mono1.then(chain.filter(exchange)).then(mono2);
    
    		return ret;
    	}
    }

import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.boot.SpringApplication;
    import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
    import org.springframework.boot.autoconfigure.SpringBootApplication;
    import org.springframework.boot.autoconfigure.web.servlet.error.ErrorMvcAutoConfiguration;
    import org.springframework.cloud.gateway.route.RouteLocator;
    import org.springframework.cloud.gateway.route.builder.RouteLocatorBuilder;
    import org.springframework.context.annotation.Bean;
    import org.springframework.context.annotation.Configuration;
    
    @Configuration
    @SpringBootApplication
    @EnableAutoConfiguration(exclude = { ErrorMvcAutoConfiguration.class })
    public class SpringCloudGatewayApplication {
    
    	public static void main(String[] args) {
    		SpringApplication.run(SpringCloudGatewayApplication.class, args);
    	}
    
    	@Autowired
    	private GatewayFilter1 filter1;
    
    	@Autowired
    	private GatewayFilter2 filter2;
    
    	@Bean
    	public RouteLocator myRoutes(RouteLocatorBuilder builder) {
    		return builder.routes().route(p -> p.path("/**")
    				.filters(f -> f.filter(filter1, -2).filter(filter2, -2).filter(filter)).uri("no://op")).build();
    	}
    
    	@Autowired
    	private CustomFilter filter;
    }

这里要注意，order值要小于-1，因为只有小于-1（即比NettyWriteResponseFilter.WRITE\_RESPONSE\_FILTER\_ORDER小），writeWith方法才会被调用。

运行结果：

> Thread\[reactor-http-nio-2,5,main\]:GatewayFilter1:before chain.filter  
> Thread\[reactor-http-nio-2,5,main\]:GatewayFilter1:after  chain.filter  
> Thread\[reactor-http-nio-2,5,main\]:GatewayFilter1:before chain.filter in mono  
> Thread\[reactor-http-nio-2,5,main\]:GatewayFilter2:before chain.filter  
> Thread\[reactor-http-nio-2,5,main\]:GatewayFilter2:after  chain.filter  
> Thread\[reactor-http-nio-2,5,main\]:GatewayFilter2:before chain.filter in mono  
> Thread\[reactor-http-nio-2,5,main\]:CustomerFilter:before  
> Thread\[reactor-http-nio-4,5,main\]:GatewayFilter2:in chain.request  
> Thread\[reactor-http-nio-4,5,main\]:GatewayFilter1:in chain.request  
> Thread\[reactor-http-nio-2,5,main\]:GatewayFilter1:in chain.request map  
> Thread\[reactor-http-nio-2,5,main\]:GatewayFilter2:in chain.request map  
> Thread\[reactor-http-nio-4,5,main\]:CustomerFilter:after  
> Thread\[reactor-http-nio-4,5,main\]:GatewayFilter2:in chain.response  
> Thread\[reactor-http-nio-4,5,main\]:GatewayFilter1:in chain.response  
> Thread\[reactor-http-nio-4,5,main\]:GatewayFilter2:in chain.response map  
> Thread\[reactor-http-nio-4,5,main\]:GatewayFilter1:in chain.response map  
> Thread\[reactor-http-nio-2,5,main\]:GatewayFilter2:after  chain.filter in mono  
> Thread\[reactor-http-nio-2,5,main\]:GatewayFilter1:after  chain.filter in mono

可以看到执行顺序为：7 > 8 > 5 > 1 > 2 > 3 > 4 > 6

#    五、如何中止filter调用链 #

将ServerHttpResponse设置成complete就可以中止filter调用链

ServerHttpResponse response = exchange.getResponse();
    response.setStatusCode(HttpStatus.UNAUTHORIZED);
    
    return response.setComplete();

# 六、调用超时后是如何处理 #

超时可以通过如下方式配置

> spring.cloud.gateway.httpclient.connect-timeout=10000  
> spring.cloud.gateway.httpclient.response-timeout=5s

如果调用外部服务后出现超时，gateway会返回类似如下报文

> \{  
>     "timestamp": "2021-04-05T09:58:39.460+00:00",  
>     "path": "/test",  
>     "status": 504,  
>     "error": "Gateway Timeout",  
>     "message": "",  
>     "requestId": "5cee82b7-2"  
> \}

参考文档

[Concurrency in Spring WebFlux][]

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L25ldHllYXhp_size_16_color_FFFFFF_t_70]: /images/20221022/d978068266ea499dbbbc351852b6866c.png
[Concurrency in Spring WebFlux]: https://www.baeldung.com/spring-webflux-concurrency