Java实现API sign签名校验的方法详解

// 最终拼接为stringB：
orderType=1001X-UTCTime=2022-02-16T09:12:43.083ZpageSize=10X-Access-Key=app1X-Access-Token=d7b5808c3f443eb5a496225468c7e4a5pageNum=2requestFrom=IOSX-Random=341be97d9aff90c9978347f66f945b77

// 最后拼上accessSecret得到stringC：
orderType=1001X-UTCTime=2022-02-16T09:12:43.083ZpageSize=10X-Access-Key=app1X-Access-Token=d7b5808c3f443eb5a496225468c7e4a5pageNum=2requestFrom=IOSX-Random=341be97d9aff90c9978347f66f945b77&accessSecret=192006250b4c09247ec02edce69f6a2d
// md5加密得到最终签名结果sign：
sign=e1a4907ef03adee3fa8d395552814f4e

public class SignUtil {

    /**
     * 生成签名
     *
     * @param accessSecret accessSecret
     * @param url          url
     * @param headers      headers
     * @param body         post的body体
     * @param <T>          body体泛型
     * @return sign
     */
    public static <T> String sign(String accessSecret, String url, Map<String, Object> headers, T body) throws IllegalAccessException {
        Map<String, Object> signMap = new HashMap<>();
        if (headers != null) {
            signMap.putAll(headers);
        }
        Map<String, Object> paramMap = getUrlParams(url);
        if (paramMap != null) {
            signMap.putAll(paramMap);
        }
        Map<String, Object> bodyMap = getBodyParams(body);
        if (bodyMap != null) {
            signMap.putAll(bodyMap);
        }

        StringBuffer sb = new StringBuffer();
        signMap.forEach((k, v) -> {
            sb.append(k).append("=").append(v).append("&");
        });
        sb.append("accessSecret=").append(accessSecret);
        return stringToMD5(sb.toString());
    }

    private static Map<String, Object> getUrlParams(String url) {
        if (StringUtils.isBlank(url) || !url.contains("?")) {
            return null;
        }
        Map<String, Object> paramMap = new HashMap<>();
        String params = url.split("\\?")[1];
        for (String param : params.split("&")) {
            String[] p = param.split("=");
            paramMap.put(p[0], p[1]);
        }
        return paramMap;
    }

    private static <T> Map<String, Object> getBodyParams(T body) throws IllegalAccessException {
        if (body == null) {
            return null;
        }
        Map<String, Object> bodyMap = new HashMap<>();
        for (Field field : body.getClass().getDeclaredFields()) {
            field.setAccessible(true);
            bodyMap.put(field.getName(), field.get(body));
        }
        return bodyMap;
    }

    private static String stringToMD5(String plainText) {
        byte[] secretBytes = null;
        try {
            secretBytes = MessageDigest.getInstance("md5").digest(
                    plainText.getBytes());
        } catch (NoSuchAlgorithmException e) {
            throw new RuntimeException("没有这个md5算法！");
        }

        return new BigInteger(1, secretBytes).toString(16);
    }
}

public class App {
    public static void main(String[] args) throws IllegalAccessException {
        String url = "http://api.abc.com/a-service/orders?orderType=1001&requestFrom=IOS&pageNum=2&pageSize=10";
        Map<String, Object> headerMap = new HashMap<>();
        headerMap.put("X-Access-Key", "app1");
        headerMap.put("X-Access-Token", "d7b5808c3f443eb5a496225468c7e4a5");
        headerMap.put("X-UTCTime", generateDate());
        headerMap.put("X-Random", "341be97d9aff90c9978347f66f945b77");
        BodyVO body = new BodyVO(100000001L, "yangcan", new Date());

        String sign = SignUtil.sign("sdfsdfdsfdsfds", url, headerMap, body);
        System.out.println(sign);
    }

    /**
     * 获取当前时间的UTC格式
     */
    private static String generateDate() {
        Date now = new Date();
        DateFormat format = new SimpleDateFormat("EEE MMM dd HH:mm:ss z yyyy", Locale.US);
        return format.format(now);
    }

    @Data
    @AllArgsConstructor
    public static class BodyVO {
        private Long ycId;
        private String ycName;
        private Date ycTime;
    }
}