Spring Cloud Alibaba 学习 -- 5、Gateway 服务网关

以你之姓@ 2022-10-12 00:49 175阅读 0赞

> 学习视频（B站）：https://www.bilibili.com/video/BV1Mt4y1i7JW  
> GitHub 源码地址：https://github.com/tyronczt/spring-cloud-alibaba-learning
> 
> 系列文章：https://blog.csdn.net/tian330726/article/details/112910508

#### 0、简介 ####

Spring Cloud Gateway是Spring官方基于Spring 5.0，Spring Boot 2.0和Project Reactor等技术开发的网关，Spring Cloud Gateway旨在为微服务架构提供一种简单而有效的统一的API路由管理方式。Spring Cloud Gateway作为Spring Cloud生态系中的网关，目标是替代ZUUL，其不仅提供统一的路由方式，并且基于Filter链的方式提供了网关基本的功能，例如：安全，监控/埋点，和限流等。

Spring Cloud Gateway 是基于 Netty，跟 Servlet 不兼容

#### 1、引入依赖 ####

<dependency>
        <groupId>org.springframework.cloud</groupId>
        <artifactId>spring-cloud-starter-gateway</artifactId>
        <version>2.2.5.RELEASE</version>
    </dependency>
    
    <dependency>
        <groupId>com.alibaba.csp</groupId>
        <artifactId>sentinel-spring-cloud-gateway-adapter</artifactId>
        <version>1.8.0</version>
    </dependency>

#### 2、配置文件 ####

server:
      port: 9999
    spring:
      application:
        name: gateway
      # 通过网关进行映射
      cloud:
        gateway:
          discovery:
            locator:
              enabled: true
          # 配置路由
          routes:
            - id: provider_route
              uri: http://localhost:3333
              predicates:
                - Path=/provider/**
              filters:
                - StripPrefix=1

启动项目后，实现效果是下面两个地址访问结果一致：

http://localhost:9999/provider/index <==> http://localhost:3333/index

#### 3、添加 nacos 依赖 ####

<dependency>
        <groupId>com.alibaba.cloud</groupId>
        <artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>
        <version>2.2.1.RELEASE</version>
    </dependency>

#### 4、修改配置文件 ####

server:
      port: 9999
    spring:
      application:
        name: gateway
      # 通过网关进行映射
      cloud:
        gateway:
          discovery:
            locator:
              enabled: true

同理得到：http://localhost:9999/provider/index <==> http://localhost:3333/index

#### 5、基于路由限流 ####

增加配置文件GatewayRoutesConfiguration：

package com.tyron.configuration;
    import com.alibaba.csp.sentinel.adapter.gateway.common.rule.GatewayFlowRule;
    import com.alibaba.csp.sentinel.adapter.gateway.common.rule.GatewayRuleManager;
    import com.alibaba.csp.sentinel.adapter.gateway.sc.SentinelGatewayFilter;
    import com.alibaba.csp.sentinel.adapter.gateway.sc.callback.BlockRequestHandler;
    import com.alibaba.csp.sentinel.adapter.gateway.sc.callback.GatewayCallbackManager;
    import com.alibaba.csp.sentinel.adapter.gateway.sc.exception.SentinelGatewayBlockExceptionHandler;
    import org.springframework.beans.factory.ObjectProvider;
    import org.springframework.cloud.gateway.filter.GlobalFilter;
    import org.springframework.context.annotation.Bean;
    import org.springframework.context.annotation.Configuration;
    import org.springframework.core.Ordered;
    import org.springframework.core.annotation.Order;
    import org.springframework.http.HttpStatus;
    import org.springframework.http.MediaType;
    import org.springframework.http.codec.ServerCodecConfigurer;
    import org.springframework.web.reactive.function.BodyInserters;
    import org.springframework.web.reactive.function.server.ServerResponse;
    import org.springframework.web.reactive.result.view.ViewResolver;
    import org.springframework.web.server.ServerWebExchange;
    import reactor.core.publisher.Mono;
    
    import javax.annotation.PostConstruct;
    import java.util.*;
    
    @Configuration
    public class GatewayRoutesConfiguration {
        
        private final List<ViewResolver> viewResolvers;
        private final ServerCodecConfigurer serverCodecConfigurer;
    
    
        public GatewayRoutesConfiguration(ObjectProvider<List<ViewResolver>> viewResolversProvider,
                                          ServerCodecConfigurer serverCodecConfigurer) {
        
            this.viewResolvers = viewResolversProvider.getIfAvailable(Collections::emptyList);
            this.serverCodecConfigurer = serverCodecConfigurer;
        }
    
        //配置限流的异常处理
        @Bean
        @Order(Ordered.HIGHEST_PRECEDENCE)
        public SentinelGatewayBlockExceptionHandler sentinelGatewayBlockExceptionHandler() {
        
            return new SentinelGatewayBlockExceptionHandler(viewResolvers, serverCodecConfigurer);
        }
    
        //配置初始化的限流参数
        @PostConstruct
        public void initGatewayRules(){
        
            Set<GatewayFlowRule> rules = new HashSet<>();
            rules.add(
                    new GatewayFlowRule("provider_route")
                            .setCount(1)
                            .setIntervalSec(1)
            );
            GatewayRuleManager.loadRules(rules);
        }
    
        //初始化限流过滤器
        @Bean
        @Order(Ordered.HIGHEST_PRECEDENCE)
        public GlobalFilter sentinelGatewayFilter() {
        
            return new SentinelGatewayFilter();
        }
    
        //自定义限流异常页面
        @PostConstruct
        public void initBlockHandlers(){
        
            BlockRequestHandler blockRequestHandler = new BlockRequestHandler() {
        
                @Override
                public Mono<ServerResponse> handleRequest(ServerWebExchange serverWebExchange, Throwable throwable) {
        
                    Map map = new HashMap();
                    map.put("code",0);
                    map.put("msg","被限流了");
                    return ServerResponse.status(HttpStatus.OK)
                            .contentType(MediaType.APPLICATION_JSON)
                            .body(BodyInserters.fromObject(map));
                }
            };
            GatewayCallbackManager.setBlockHandler(blockRequestHandler);
        }
    }

修改application.yml：

显示效果：  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3RpYW4zMzA3MjY_size_16_color_FFFFFF_t_70_pic_center]

#### 6、基于 API 分组限流 ####

增加配置文件GatewayConfiguration：

package com.tyron.configuration;
    
    import com.alibaba.csp.sentinel.adapter.gateway.common.SentinelGatewayConstants;
    import com.alibaba.csp.sentinel.adapter.gateway.common.api.ApiDefinition;
    import com.alibaba.csp.sentinel.adapter.gateway.common.api.ApiPathPredicateItem;
    import com.alibaba.csp.sentinel.adapter.gateway.common.api.ApiPredicateItem;
    import com.alibaba.csp.sentinel.adapter.gateway.common.api.GatewayApiDefinitionManager;
    import com.alibaba.csp.sentinel.adapter.gateway.common.rule.GatewayFlowRule;
    import com.alibaba.csp.sentinel.adapter.gateway.common.rule.GatewayRuleManager;
    import com.alibaba.csp.sentinel.adapter.gateway.sc.SentinelGatewayFilter;
    import com.alibaba.csp.sentinel.adapter.gateway.sc.callback.BlockRequestHandler;
    import com.alibaba.csp.sentinel.adapter.gateway.sc.callback.GatewayCallbackManager;
    import com.alibaba.csp.sentinel.adapter.gateway.sc.exception.SentinelGatewayBlockExceptionHandler;
    import org.springframework.beans.factory.ObjectProvider;
    import org.springframework.cloud.gateway.filter.GlobalFilter;
    import org.springframework.context.annotation.Bean;
    import org.springframework.context.annotation.Configuration;
    import org.springframework.core.Ordered;
    import org.springframework.core.annotation.Order;
    import org.springframework.http.HttpStatus;
    import org.springframework.http.MediaType;
    import org.springframework.http.codec.ServerCodecConfigurer;
    import org.springframework.web.reactive.function.BodyInserters;
    import org.springframework.web.reactive.function.server.ServerResponse;
    import org.springframework.web.reactive.result.view.ViewResolver;
    import org.springframework.web.server.ServerWebExchange;
    import reactor.core.publisher.Mono;
    
    import javax.annotation.PostConstruct;
    import java.util.*;
    
    @Configuration
    public class GatewayConfiguration {
        
    
        private final List<ViewResolver> viewResolvers;
        private final ServerCodecConfigurer serverCodecConfigurer;
    
    
        public GatewayConfiguration(ObjectProvider<List<ViewResolver>> viewResolversProvider,
                                    ServerCodecConfigurer serverCodecConfigurer) {
        
            this.viewResolvers = viewResolversProvider.getIfAvailable(Collections::emptyList);
            this.serverCodecConfigurer = serverCodecConfigurer;
        }
    
        //配置限流的异常处理
        @Bean
        @Order(Ordered.HIGHEST_PRECEDENCE)
        public SentinelGatewayBlockExceptionHandler sentinelGatewayBlockExceptionHandler() {
        
            return new SentinelGatewayBlockExceptionHandler(viewResolvers, serverCodecConfigurer);
        }
    
        //配置初始化的限流参数
        @PostConstruct
        public void initGatewayRules(){
        
            Set<GatewayFlowRule> rules = new HashSet<>();
            rules.add(new GatewayFlowRule("provider_api1").setCount(1).setIntervalSec(1));
            rules.add(new GatewayFlowRule("provider_api2").setCount(1).setIntervalSec(1));
            GatewayRuleManager.loadRules(rules);
        }
    
        //初始化限流过滤器
        @Bean
        @Order(Ordered.HIGHEST_PRECEDENCE)
        public GlobalFilter sentinelGatewayFilter() {
        
            return new SentinelGatewayFilter();
        }
    
        //自定义限流异常页面
        @PostConstruct
        public void initBlockHandlers(){
        
            BlockRequestHandler blockRequestHandler = new BlockRequestHandler() {
        
                @Override
                public Mono<ServerResponse> handleRequest(ServerWebExchange serverWebExchange, Throwable throwable) {
        
                    Map map = new HashMap();
                    map.put("code",0);
                    map.put("msg","被限流了");
                    return ServerResponse.status(HttpStatus.OK)
                            .contentType(MediaType.APPLICATION_JSON)
                            .body(BodyInserters.fromObject(map));
                }
            };
            GatewayCallbackManager.setBlockHandler(blockRequestHandler);
        }
    
        //自定义API分组
        @PostConstruct
        private void initCustomizedApis(){
        
            Set<ApiDefinition> definitions = new HashSet<>();
            ApiDefinition api1 = new ApiDefinition("provider_api1")
                    .setPredicateItems(new HashSet<ApiPredicateItem>(){
        {
        
                        add(new ApiPathPredicateItem().setPattern("/provider/api1/**")
                                .setMatchStrategy(SentinelGatewayConstants.URL_MATCH_STRATEGY_PREFIX));
                    }});
            ApiDefinition api2 = new ApiDefinition("provider_api2")
                    .setPredicateItems(new HashSet<ApiPredicateItem>(){
        {
        
                        add(new ApiPathPredicateItem().setPattern("/provider/api2/demo1"));
                    }});
            definitions.add(api1);
            definitions.add(api2);
            GatewayApiDefinitionManager.loadApiDefinitions(definitions);
        }
    }

修改application.yml：

server:
      port: 9999
    spring:
      application:
        name: gateway
      # 通过网关进行映射
      cloud:
        gateway:
          discovery:
            locator:
              enabled: true
          # 配置路由
    #      routes:
    #        - id: provider_route
    #          uri: http://localhost:3333
    #          predicates:
    #            - Path=/provider/**
    #          filters:
    #            - StripPrefix=1

provider项目中增加Controller方法：

@GetMapping("/api1/demo1")
        public String demo1() {
        
            return "/api1/demo1";
        }
    
        @GetMapping("/api1/demo2")
        public String demo2() {
        
            return "/api1/demo2";
        }
    
        @GetMapping("/api2/demo1")
        public String demo3() {
        
            return "/api2/demo1";
        }
    
        @GetMapping("/api2/demo2")
        public String demo4() {
        
            return "/api2/demo2";
        }

显示效果，当访问api1的接口时会被限流，api2则不会：

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3RpYW4zMzA3MjY_size_16_color_FFFFFF_t_70_pic_center 1]

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3RpYW4zMzA3MjY_size_16_color_FFFFFF_t_70_pic_center]: /images/20221005/a238bcd1d307404b999b8446345e46ed.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3RpYW4zMzA3MjY_size_16_color_FFFFFF_t_70_pic_center 1]: /images/20221005/14736f53580b4b2296d5aa0ca9139ee0.png