gateway统一异常处理返回JSON数据

你的名字 2022-10-10 11:10 250阅读 0赞

自定义异常处理逻辑

package com.will.gateway.exception;
    
    
    import org.springframework.boot.autoconfigure.web.ErrorProperties;
    import org.springframework.boot.autoconfigure.web.ResourceProperties;
    import org.springframework.boot.autoconfigure.web.reactive.error.DefaultErrorWebExceptionHandler;
    import org.springframework.boot.web.reactive.error.ErrorAttributes;
    import org.springframework.context.ApplicationContext;
    import org.springframework.web.reactive.function.server.RouterFunction;
    import org.springframework.web.reactive.function.server.RouterFunctions;
    import org.springframework.web.reactive.function.server.ServerRequest;
    import org.springframework.web.reactive.function.server.ServerResponse;
    
    import java.util.HashMap;
    import java.util.Map;
    
    import static org.springframework.web.reactive.function.server.RequestPredicates.all;
    
    /**
     * 全局异常 handler
     */
    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;
            }
            if (error instanceof CustomException) {
                CustomException customException = (CustomException) error;
                return response(code, customException.getMessage());
            }
            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(all(), this::renderErrorResponse);
        }
    
        /**
         * 根据code获取对应的HttpStatus
         *
         * @param errorAttributes
         */
        @Override
        protected int getHttpStatus(Map<String, Object> errorAttributes) {
    //        return (int) errorAttributes.get("code");
            return 200;
        }
    
        /**
         * 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("msg", errorMessage);
            map.put("data", null);
            return map;
        }
    
    }

重写ErrorWebFluxAutoConfiguration覆盖默认的异常处理

package com.will.gateway.exception;
    
    
    import org.springframework.beans.factory.ObjectProvider;
    import org.springframework.boot.autoconfigure.AutoConfigureBefore;
    import org.springframework.boot.autoconfigure.condition.ConditionalOnClass;
    import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
    import org.springframework.boot.autoconfigure.condition.ConditionalOnWebApplication;
    import org.springframework.boot.autoconfigure.condition.SearchStrategy;
    import org.springframework.boot.autoconfigure.web.ResourceProperties;
    import org.springframework.boot.autoconfigure.web.ServerProperties;
    import org.springframework.boot.autoconfigure.web.reactive.WebFluxAutoConfiguration;
    import org.springframework.boot.context.properties.EnableConfigurationProperties;
    import org.springframework.boot.web.reactive.error.DefaultErrorAttributes;
    import org.springframework.boot.web.reactive.error.ErrorAttributes;
    import org.springframework.boot.web.reactive.error.ErrorWebExceptionHandler;
    import org.springframework.context.ApplicationContext;
    import org.springframework.context.annotation.Bean;
    import org.springframework.context.annotation.Configuration;
    import org.springframework.core.annotation.Order;
    import org.springframework.http.codec.ServerCodecConfigurer;
    import org.springframework.web.reactive.config.WebFluxConfigurer;
    import org.springframework.web.reactive.result.view.ViewResolver;
    
    import java.util.stream.Collectors;
    
    /**
     * 覆盖默认的异常处理
     */
    @Configuration(proxyBeanMethods = false)
    @ConditionalOnWebApplication(type = ConditionalOnWebApplication.Type.REACTIVE)
    @ConditionalOnClass(WebFluxConfigurer.class)
    @AutoConfigureBefore(WebFluxAutoConfiguration.class)
    @EnableConfigurationProperties({ ServerProperties.class, ResourceProperties.class })
    public class ErrorHandlerConfiguration {
    
        private final ServerProperties serverProperties;
    
        public ErrorHandlerConfiguration(ServerProperties serverProperties) {
            this.serverProperties = serverProperties;
        }
    
        @Bean
        @ConditionalOnMissingBean(value = ErrorWebExceptionHandler.class, search = SearchStrategy.CURRENT)
        @Order(-1)
        public ErrorWebExceptionHandler errorWebExceptionHandler(ErrorAttributes errorAttributes,
                                                                 ResourceProperties resourceProperties, ObjectProvider<ViewResolver> viewResolvers,
                                                                 ServerCodecConfigurer serverCodecConfigurer, ApplicationContext applicationContext) {
            JsonExceptionHandler exceptionHandler = new JsonExceptionHandler(errorAttributes,
                    resourceProperties, this.serverProperties.getError(), applicationContext);
            exceptionHandler.setViewResolvers(viewResolvers.orderedStream().collect(Collectors.toList()));
            exceptionHandler.setMessageWriters(serverCodecConfigurer.getWriters());
            exceptionHandler.setMessageReaders(serverCodecConfigurer.getReaders());
            return exceptionHandler;
        }
    
        @Bean
        @ConditionalOnMissingBean(value = ErrorAttributes.class, search = SearchStrategy.CURRENT)
        public DefaultErrorAttributes errorAttributes() {
            return new DefaultErrorAttributes(this.serverProperties.getError().isIncludeException());
        }
    
    }

在errorWebExceptionHandler中使用自己写的异常处理逻辑。

可能存在的问题，我之前spring-boot用的是2.2.3RELEASE异常处理的时候报错

java.lang.NoSuchMethodError: org.springframework.http.server.reactive.ServerHttpResponse.setRawStatusCode(Ljava/lang/Integer;)Z
    	at org.springframework.web.reactive.function.server.DefaultServerResponseBuilder$AbstractServerResponse.writeStatusAndHeaders(DefaultServerResponseBuilder.java:356) ~[spring-webflux-5.2.4.RELEASE.jar:5.2.4.RELEASE]
    	at org.springframework.web.reactive.function.server.DefaultServerResponseBuilder$AbstractServerResponse.writeTo(DefaultServerResponseBuilder.java:344) ~[spring-webflux-5.2.4.RELEASE.jar:5.2.4.RELEASE]

根据异常信息找到DefaultServerResponseBuilder类发现response.setRawStatusCode(this.statusCode)该方法不存在，response.setRawStatusCode(this.statusCode)是spring-boot在2.2.5RELEASE版本提出来的，将spring-boot版本改到2.2.5RELEASE解决