/**
 * Get请求
 */
@GetMapping
protected void doGet(HttpServletRequest request, HttpServletResponse response, String prefix)
        throws ServletException, IOException {

    String endpoint = this.endpoint.replace("http://", "").replace("https://", ""); // 请填写您的 endpoint。
    String host = "http://" + this.bucketName + "." + endpoint; // host的格式为 bucketname.endpoint
    // callbackUrl为 上传回调服务器的URL，请将下面的IP和Port配置为您自己的真实信息。
    // String callbackUrl = "http://88.88.88.88.:8888";
    String dir = Constants.FILE_PREFIX; // 用户上传文件时指定的前缀。
    if (StringUtils.isNotBlank(prefix)) {
        dir += prefix + "_"; // 用户上传文件时指定的前缀。
    }

    OSS client = aliOssService.getOssClient();
    try {
        long expireTime = 30;
        long expireEndTime = System.currentTimeMillis() + expireTime * 1000;
        Date expiration = new Date(expireEndTime);
        PolicyConditions policyConds = new PolicyConditions();
        policyConds.addConditionItem(PolicyConditions.COND_CONTENT_LENGTH_RANGE, 0, 1048576000);
        // policyConds.addConditionItem(MatchMode.StartWith, PolicyConditions.COND_KEY, dir);

        String postPolicy = client.generatePostPolicy(expiration, policyConds);
        byte[] binaryData = postPolicy.getBytes("utf-8");
        String encodedPolicy = BinaryUtil.toBase64String(binaryData);
        String postSignature = client.calculatePostSignature(postPolicy);

        JSONObject ja1 = new JSONObject();
        ja1.put("accessid", this.accessKeyId);
        ja1.put("policy", encodedPolicy);
        ja1.put("signature", postSignature);
        ja1.put("dir", dir);
        ja1.put("host", host);
        ja1.put("expire", String.valueOf(expireEndTime / 1000));
        // respMap.put("expire", formatISO8601Date(expiration));

        JSONObject jasonCallback = new JSONObject();
        // jasonCallback.put("callbackUrl", callbackUrl);
        jasonCallback.put("callbackBody",
                "filename=${object}&size=${size}&mimeType=${mimeType}&height=${imageInfo.height}&width=${imageInfo.width}");
        jasonCallback.put("callbackBodyType", "application/x-www-form-urlencoded");
        String base64CallbackBody = BinaryUtil.toBase64String(jasonCallback.toString().getBytes());
        ja1.put("callback", base64CallbackBody);


        // System.out.println(ja1.toString());
        response.setHeader("Access-Control-Allow-Origin", "*");
        response.setHeader("Access-Control-Allow-Methods", "GET, POST");
        response(request, response, ja1.toString());
    } catch (Exception e) {
        e.printStackTrace();
    }
}