修改经过Spring Gateway的Json数据

技术分享 3年前 (2023-09-18) 0 999+

背景

使用Spring Cloud Gateway作为网关时经常会需要对报文内的json数据进行修改，但是目前看到的实现方法看起来都很复杂，这里提供一种使用Spring官方提供的ModifyRequestBodyGatewayFilterFactory类来修改json报文的方法

依赖

Spring Boot版本：2.7.15
Hutool: 5.8.21
Java: 11

实现逻辑

实现分为两个部分

filter：在自定义的filter内注入ModifyRequestBodyGatewayFilterFactory类，然后调用，该类会自动完成对修改结果的重新包装。
service: 自定义的service实现ModifyRequestBodyGatewayFilterFactory类的RewriteFunction<T, R>接口完成对json数据的处理

自定义filter

@Component @Slf4j public class RequestModifyFilter implements GlobalFilter, Ordered {     @Autowired     private ModifyRequestBodyGatewayFilterFactory modifyRequestBodyFilter;     @Autowired     private JsonRequestBodyRewriteService jsonRequestBodyRewriteService;      @Override     public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {         MediaType mediaType = exchange.getRequest().getHeaders().getContentType();         if (MediaType.APPLICATION_json.isCompatibleWith(mediaType)) {             // 纯json报文处理逻辑             return modifyRequestBodyFilter                     .apply(                             new ModifyRequestBodyGatewayFilterFactory.Config()                                     .setRewriteFunction(byte[].class, byte[].class, jsonRequestBodyRewriteService))                     .filter(exchange, chain);         } else {             return filter(exchange, chain);         }      }      @Override     public int getOrder() {         return OrderConstant.REQUEST_MODIFY_FILTER.getOrder();     } }

自定义service

@Service @Slf4j public class JsonRequestBodyRewriteService implements RewriteFunction<byte[], byte[]> {     @Override     public Publisher<byte[]> apply(ServerWebExchange exchange, byte[] body) {         jsonObject request = jsonUtil.parseObj(body);         log.info("原始报文:{}", request.toString());         try {             request.set("empId", "2345");             request.set("department", "Engineering");              log.info("修改后报文:{}", request);             return Mono.just(request.toString().getBytes());         } catch (Exception e) {             log.error("修改报文时出错",e);             throw e;         }     } }