切面編程-自定義注解-統(tǒng)一異常攔截-反射

很多有安全要求笑旺，或是系統(tǒng)對接的接口都需要進行簽名驗簽文留。一般我們都是寫個工具類好唯，哪個接口需要自己調，把簽名字段組織好扔進去燥翅。
閑著蛋疼骑篙，寫了個接口層的驗簽注解，包裝了json返回格式权旷，可以自定義替蛉。

1.先定義兩個注解

//標識簽名接口方法
@Target({ElementType.METHOD})
@Retention(RetentionPolicy.RUNTIME)
public @interface Signature {
    //入?yún)⒅幸粋€來源標識，綁定了對應的秘鑰鹽值登配置
    String configKey() default "source";
    //入?yún)⒅械暮灻侄蚊袈龋勺远x
    String signKey() default "sign";
    //簽名算法
    String algorithm() default "MD5";
}

//標識簽名字段
@Target({ElementType.FIELD})
@Retention(RetentionPolicy.RUNTIME)
public @interface SignField {
}

2.切面及通知定義

@Aspect
@Component
@Slf4j
public class SignAspect {

    // 簽名開關
    private Boolean signSwitch;

    // 配置 dao
    private ConfigMapper configMapper;

    public SignAspect(Boolean signSwitch, ConfigMapper configMapper) {
        this.signSwitch = signSwitch;
        this.configMapper = configMapper;
    }

    @Pointcut("@annotation(com.***.signature.Signature)")
    public void pointCut(){}

    @Around("pointCut()")
    public Object doAround(ProceedingJoinPoint pjp) throws Throwable {
        //簽名開關
        if (Boolean.FALSE.equals(signSwitch)) return pjp.proceed();
        // 取body參數(shù) @SignField
        Object[] params = pjp.getArgs();
        if (params == null || params.length == 0){
            log.error("signAspect doAround params null");
            throw new KKXExeception("驗簽異常,參數(shù)為空!");
        }
        Object param = params[0];
        Map<String,Field> fieldMap = getAllFields(param.getClass());
        MethodSignature methodSignature = ((MethodSignature)pjp.getSignature());
        Method method = methodSignature.getMethod();
        Signature signature = method.getAnnotation(Signature.class);
        Field signKey = fieldMap.get(signature.signKey());
        signKey.setAccessible(true);
        String sign = (String) signKey.get(param);
        if (StringUtil.isEmpty(sign)) throw new KKXExeception("驗簽異常,參數(shù)sign為空躲查！");
        // 查詢配置
        Field configKey = fieldMap.get(signature.configKey());
        configKey.setAccessible(true);
        String source = (String) configKey.get(param);
        if (StringUtil.isEmpty(source)) throw new KKXExeception("驗簽異常,配置參數(shù)為空！");
        String salt = configMapper.querySignKey(source);
        if (StringUtil.isEmpty(salt)) throw new KKXExeception("驗簽異常,未加載到簽名配置译柏！");
        StringBuilder sb = getSignStr(param,fieldMap);
        String actualSign = SignatureUtil.sign(sb,salt);
        if (sign.equals(actualSign)){
            return pjp.proceed();
        }
        throw new KKXExeception("98","簽名驗證失敗");
    }

    private StringBuilder getSignStr(Object param,Map<String,Field> fieldMap) throws Throwable {
        StringBuilder sb = new StringBuilder();
        int i = 0;
        for (Field field : fieldMap.values()) {
            SignField annotation = field.getAnnotation(SignField.class);
            if (annotation == null) {
                continue;
            }
            String name = field.getName();
            field.setAccessible(true);
            Object val = field.get(param);
            if (i++ > 0) sb.append("&");
            sb.append(name).append("=").append(val);
        }
        return sb;
    }


    @AfterThrowing(value = "pointCut()", throwing="e")
    public void afterThrowing(Throwable e) {
        log.error("signAspect afterThrowing ",e);
        if(e instanceof KKXExeception) {
            throw (KKXExeception)e;
        }
        throw new KKXExeception("","驗簽異常");
    }

    /**
     * 獲取本類及其父類的屬性的方法
     * @param clazz 當前類對象
     * @return 字段數(shù)組
     */
    private static Map<String,Field> getAllFields(Class<?> clazz) {
        List<Field> fieldList = new ArrayList<>();
        while (clazz != null){
            fieldList.addAll(new ArrayList<>(Arrays.asList(clazz.getDeclaredFields())));
            clazz = clazz.getSuperclass();
        }
        Map<String,Field> fieldMap = new HashMap<>();
        for (Field e : fieldList) {
            fieldMap.put(e.getName(), e);
        }
        return fieldMap;
    }
}

3.統(tǒng)一異常攔截

...略

4.bean注冊

因為需要裝配到具體的項目中镣煮，需要進行spring裝配。
這個有很多方式.

• 引用jar封裝成springboot-starter @bean + springboot spi定義自動裝配
• 主項目直接定義@componentscan 掃描到引入jar中的@component
• 主項目中@bean 注冊（暫采用）

@Bean
public SignAspect signAspect(@Value("${app.signSwitch:true}") Boolean signSwitch, ConfigMapper configMapper){
    return new SignAspect(signSwitch,configMapper);
}