SpringCloud 实践笔记—服务网关-Gateway（四）

╰半夏微凉° 2022-10-02 14:52 126阅读 0赞

参考网站

[https://blog.csdn.net/forezp/article/details/83792388][https_blog.csdn.net_forezp_article_details_83792388]

简介

Spring Cloud Gateway是Spring Cloud官方推出的第二代网关框架，取代Zuul网关。

1、pom

<?xml version="1.0" encoding="UTF-8"?>
    <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
             xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
        <modelVersion>4.0.0</modelVersion>
        <parent>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-parent</artifactId>
            <version>2.1.6.RELEASE</version>
            <relativePath/> 
        </parent>
        <groupId>com.gray</groupId>
        <artifactId>getway</artifactId>
        <version>0.0.1-SNAPSHOT</version>
        <name>getway</name>
        <description>Demo project for Spring Boot</description>
    
        <properties>
            <java.version>1.8</java.version>
            <spring-cloud.version>Greenwich.SR1</spring-cloud.version>
        </properties>
    
        <dependencies>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-starter-config</artifactId>
            </dependency>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-starter-gateway</artifactId>
            </dependency>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
            </dependency>
    
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-starter-netflix-hystrix</artifactId>
            </dependency>
    
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter-webflux</artifactId>
            </dependency>
    
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter-test</artifactId>
                <scope>test</scope>
            </dependency>
        </dependencies>
    
        <dependencyManagement>
            <dependencies>
                <dependency>
                    <groupId>org.springframework.cloud</groupId>
                    <artifactId>spring-cloud-dependencies</artifactId>
                    <version>${spring-cloud.version}</version>
                    <type>pom</type>
                    <scope>import</scope>
                </dependency>
            </dependencies>
        </dependencyManagement>
    
        <build>
            <plugins>
                <plugin>
                    <groupId>org.springframework.boot</groupId>
                    <artifactId>spring-boot-maven-plugin</artifactId>
                </plugin>
            </plugins>
        </build>
    
    </project>

2、bootstrap.yml配置

spring:
      cloud:
        config:
          discovery:
            enabled: true
            service-id: CONFIG
    #      profile: dev
          name: getway,rabbitmq
          label: master
    eureka:
      client:
        service-url:
          defaultZone: http://localhost:8761/eureka/

配置中心的getway-dev.yml 配置

spring:
      application:
        name: gateway
      cloud:
        gateway:
          discovery:
            locator:
              enabled: true
    logging:
      level:
        org.springframework.cloud.gateway: trace
        org.springframework.http.server.reactive: debug
        org.springframework.web.reactive: debug
        reactor.ipc.netty: debug

3、启动类添加 @SpringCloudApplication

4、filter 拦截并校验token 传入url校验

@Component
    public class ApiGlobalFilter implements GlobalFilter {
    
        @Override
        public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {
            String token = exchange.getRequest().getQueryParams().getFirst("token");
            if (StringUtils.isBlank(token)) {
                ServerHttpResponse response = exchange.getResponse();
                Map<String, Object> message = new HashMap<>();
                message.put("status", -1);
                message.put("data", "鉴权失败");
                byte[] bits = message.toString().getBytes(StandardCharsets.UTF_8);
                DataBuffer buffer = response.bufferFactory().wrap(bits);
                response.setStatusCode(HttpStatus.UNAUTHORIZED);
                response.getHeaders().add("Content-Type", "text/json;charset=UTF-8");
                return response.writeWith(Mono.just(buffer));
            }
            return chain.filter(exchange);
        }
    }

5、异常处理（指其他服务 在中途服务挂了，需要返回的临时信息）

/**
     * 自定义异常处理
     * SpringBoot 提供了默认的异常处理类，这显然不符合我们的预期
     * 因此需要重写此类，返回统一的 JSON 格式
     */
    public class JsonExceptionHandler extends DefaultErrorWebExceptionHandler {
    
        public JsonExceptionHandler(ErrorAttributes errorAttributes, ResourceProperties resourceProperties,
                                    ErrorProperties errorProperties, ApplicationContext applicationContext) {
            super(errorAttributes, resourceProperties, errorProperties, applicationContext);
        }
    
        /**
         * 获取异常属性
         */
        @Override
        protected Map<String, Object> getErrorAttributes(ServerRequest request, boolean includeStackTrace) {
            int code = 500;
            Throwable error = super.getError(request);
            if (error instanceof org.springframework.cloud.gateway.support.NotFoundException) {
                code = 404;
            }
            return response(code, this.buildMessage(request, error));
        }
    
        /**
         * 指定响应处理方法为 JSON 处理的方法
         * @param errorAttributes
         */
        @Override
        protected RouterFunction<ServerResponse> getRoutingFunction(ErrorAttributes errorAttributes) {
            return RouterFunctions.route(RequestPredicates.all(), this::renderErrorResponse);
        }
    
        /**
         * 根据 code 获取对应的 HttpStatus
         * @param errorAttributes
         */
        @Override
        protected HttpStatus getHttpStatus(Map<String, Object> errorAttributes) {
            int statusCode = (int) errorAttributes.get("code");
            return HttpStatus.valueOf(statusCode);
        }
    
        /**
         * 构建异常信息
         * @param request
         * @param ex
         * @return
         */
        private String buildMessage(ServerRequest request, Throwable ex) {
            StringBuilder message = new StringBuilder("Failed to handle request [");
            message.append(request.methodName());
            message.append(" ");
            message.append(request.uri());
            message.append("]");
            if (ex != null) {
                message.append(": ");
                message.append(ex.getMessage());
            }
            return message.toString();
        }
    
        /**
         * 构建返回的 JSON 数据格式
         * @param status        状态码
         * @param errorMessage  异常信息
         * @return
         */
        public static Map<String, Object> response(int status, String errorMessage) {
            Map<String, Object> map = new HashMap<>();
            map.put("code", status);
            map.put("message", errorMessage);
            map.put("data", null);
            return map;
        }
    
    }

把其添加到bean中

@SpringBootConfiguration
    @EnableConfigurationProperties({ServerProperties.class, ResourceProperties.class})
    public class ErrorHandlerConfiguration {
    
        private final ServerProperties serverProperties;
    
        private final ApplicationContext applicationContext;
    
        private final ResourceProperties resourceProperties;
    
        private final List<ViewResolver> viewResolvers;
    
        private final ServerCodecConfigurer serverCodecConfigurer;
    
        public ErrorHandlerConfiguration(ServerProperties serverProperties,
                                         ResourceProperties resourceProperties,
                                         ObjectProvider<List<ViewResolver>> viewResolversProvider,
                                         ServerCodecConfigurer serverCodecConfigurer,
                                         ApplicationContext applicationContext) {
            this.serverProperties = serverProperties;
            this.applicationContext = applicationContext;
            this.resourceProperties = resourceProperties;
            this.viewResolvers = viewResolversProvider.getIfAvailable(Collections::emptyList);
            this.serverCodecConfigurer = serverCodecConfigurer;
        }
    
        /**
         * gateway 启动时执行此方法，将 JsonExceptionHandler 注入到 Spring 容器中
         * 以便发生异常时执行自定义的 JsonExceptionHandler
         * @param errorAttributes
         * @return
         */
        @Bean
        @Order(Ordered.HIGHEST_PRECEDENCE)
        public ErrorWebExceptionHandler errorWebExceptionHandler(ErrorAttributes errorAttributes) {
            JsonExceptionHandler exceptionHandler = new JsonExceptionHandler(
                    errorAttributes,
                    this.resourceProperties,
                    this.serverProperties.getError(),
                    this.applicationContext);
            exceptionHandler.setViewResolvers(this.viewResolvers);
            exceptionHandler.setMessageWriters(this.serverCodecConfigurer.getWriters());
            exceptionHandler.setMessageReaders(this.serverCodecConfigurer.getReaders());
            return exceptionHandler;
        }
    }

[https_blog.csdn.net_forezp_article_details_83792388]: https://blog.csdn.net/forezp/article/details/83792388