springboot如何根据配置屏蔽接口返回字段

目录

• springboot根据配置屏蔽接口返回字段
• 1.类的数据域
• 2.开启的注解
• 3.json过滤器
• 4.过滤器切面
• 5.如何使用
• 总结

springboot根据配置屏蔽接口返回字段

很多时候就是为了偷懒，swagger可以屏蔽接口文档中的字段，却不能屏蔽真实返回的数据，故而需要再controller返回的时候再做处理

参考了springboot2 jackson实现动态返回类字段，做了一些改动

经验证对简单接口，还可以，稍微复杂的嵌套就不行，可以使用@JsonIgnore,路径为

com.fasterXML.jackson.annotation.JsonIgnore

<dependency>
            <groupId>org.ASPectj</groupId>
            <artifactId>aspectjweaver</artifactId>
            <version>1.9.6</version>
        </dependency>

1.类的数据域

import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;

@NoArgsConstructor
@AllArgsConstructor
@Data
public class JsonFields {
js
    boolean include = true;

    String[] fields = {};

}

2.开启的注解

写在controller的方法上

import Java.lang.annotation.*;

@Target({ ElementType.PARAMETER, ElementType.METHOD})
@Retention(RetentionPolicy.RUNTIME)
@Documented
public @interface JsonInclude {
    /**
     * 排除
     * @return
     */
    boolean include() default true;

    /**
     * 字段类型
     * @return
     */
    Class clazz();

    /**
     * 过滤的字段名
     * @return
     */
    String[] fields() default {};
}

3.json过滤器

import com.fasterxml.jackson.core.JsonGenerator;
import com.fasterxml.jackson.databind.SerializerProvider;
import com.fasterxml.jackson.databind.ser.BeanPropertyFilter;
import com.fasterxml.jackson.databind.ser.FilterProvider;
import com.fasterxml.jackson.databind.编程ser.PropertyWriter;
import com.fasterxml.jackson.databind.ser.PropertyFilter;
import com.fasterxml.jackson.databind.ser.impl.SimpleBeanPropertyFilter;

import java.util.HashMap;
import java.util.Map;

public class JsonFilter extends FilterProvider {

    /**
     * 对于规则我们采用 ThreadLocal 封装，防止出现线程安全问题
     */
    private static final ThreadLocal<Map<Class<?>, JsonFields>> include = new ThreadLocal<>();

    /**
     * 清空规则
     */
    public static void clear() {
        include.remove();
    }


    /**
     * 设置过滤规则
     * @param clazz 规则
     */
    public static void add(boolean isInclude, Class<?> clazz, String... fields) {
        Map<Class<?>, JsonFields> map = include.get();
        if (map == null) {
            map = new HashMap<>();
         编程客栈   include.set(map);
        }
        JsonFields jsonFields = new JsonFields(isInclude,fields);
        map.put(clazz, jsonFields);
    }

    /**
     * 重写规律规则
     */
    @Override
    public PropertyFilter findPropertyFilter(Object filterId, Object valueToFilter) {
        return new SimpleBeanPropertyFilter() {
            @Override
            public void serializeAsField(
                    Object pojo,
                    JsonGenerator jg,
                    SerializerProvider sp,
                    PropertyWriter pw
            ) throws Exception {
                if (apply(pojo.getClass(), pw.getName())) {
                    pw.serializeAsField(pojo, jg, sp);
                } else if (!jg.canOmitFields()) {
                    pw.serializeAsOmittedField(pojo, pythonjg, sp);
                }
            }
        };
    }

    @Deprecated
    @Override
    public BeanPropertyFilter findFilter(Object filterId) {
        throw new UnsupportedOperationException("不支持访问即将过期的过滤器");
    }

    /**
     * 判断该字段是否需要，返回 true 序列化，返回 false 则过滤
     * @param type 实体类类型
     * @param name 字段名
     */
    public boolean apply(Class<?> type, String name) {
        Map<Class<?>, JsonFields> map = include.get();
        if (map == null) {
            return true;
        }
        JsonFields jsonFields = map.get(type);
        String[] fields = jsonFields.getFields();
        if (jsonFields.isInclude()){
            for (String field : fields) {
                if (field.equals(name)) {
                    return true;
                }
            }
            return false;
        } else{
            for (String field : fields) {
                if (field.equals(name)) {
                    return false;
                }
            }
            return true;
        }
    }
}

4.过滤器切面

JsonFilter.clear();解决多线程下面的并发的问题

import lombok.extern.slf4j.Slf4j;
import org.aspectj.lang.JoinPoint;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Before;
import org.aspectj.lang.annotation.Pointcut;
import org.aspectj.lang.reflect.MethodSignature;
import org.springframework.stereotype.Component;

import java.lang.reflect.Method;

@Slf4j
@Component
@Aspect
public class JsonFilterAop {

    @Pointcut("@annotation(com.tt.framework.web.filter.JsonInclude)")
    public void controllerAspect(){}


    /**
     * （1）@annotation：用来拦截所有被某个注解修饰的方法
     * （2）@within：用来拦截所有被某个注解修饰的类
     * （3）within：用来指定扫描的包的范围
     */
    @Before("controllerAspect()")
    public void doBefore(JoinPoint joinPoint) throws Throwable{
        JsonFilter.clear();
        //从切面织入点处通过反射机制获取织入点处的方法
        MethodSignature signature = (MethodSignature) joinPoint.getSignature();
        //获取切入点所在的方法
        Method method = signature.getMethod();
        JsonInclude jsonInclude = method.getAnnotation(JsonInclude.class);
        JsonFilter.add(jsonInclude.include(),jsonInclude.clazz(),jsonInclude.fields());
    }


}

5.如何使用

启动类增加此过滤器

@Slf4j
@SpringBootApplication
public class FayServerApplication {

    public static void main(String[] args) {
        try {
            ConfigurableApplicationContext context = SpringApplication.run(FayServerApplication.class, args);
            ObjectMapper objectMapper = context.getBean(ObjectMapper.class);
            objectMapper.setFilterProvider(new JsonFilter());

        } finally {
            log.info("server start finish");
        }
    }
}

include = true包含则表示仅显示包含的数据，include = false则排除这配置的fields，显示没有配置的字段。

没有此注解的则不受影响

 @JsonInclude(include = true,clazz = LxrJbhYsth.class,fields = {"dg","mz"})
    @ApiOperation("金不换规则")
    @GetMapping("jbhRule")
    public ResponseResult<List<LxrJbhYsth>> jbhRule(String dg){
        List<LxrJbhYsth> lxrJbhYsths = extLxrJbhYsthService.selectByDg(dg);
        ResponseResult<List<LxrJbhYsth>> resp = new ResponseResult<>(true);
        resp.setData(lxrJbhYsths);
        return resp;
    }

总结

以上为个人经验，希望能给大家一个参考，也希望大家多多支持编程客栈js(www.devze.com)。