微信小程序基于腾讯云对象存储的图片上传功能

Z时代
2024-01-10
分类：综合

在使用腾讯云对象存储之前，公司一直使用的是传统的FTP的上传模式，而随着用户量的不断增加，FTP所暴露出来的问题也越来越多，1.传输效率低，上传速度慢。2.时常有上传其他文件来攻击服务器，安全上得不到保障。所以我们在经过慎重考虑觉得使用第三方的云存储服务。

在最开始的时候我们在腾讯云与阿里云中选择，最终我们选择腾讯云，腾讯云在文件上传用时方面的性能比较突出，文件越大表现越好；在下载用时方面表现略优于阿里云；文件删除用时方面总体速度略逊于，但在不同大小文件删除用时上都比较稳定。当然这与我们主要用于开发微信小程序是有着密切的关系。

在我们酷客多小程序使用腾讯云对象存储的时候除了直接使用 API 接口外，COS 提供了丰富多样的 SDK 给我们使用，可是在他提供的SDK中并没有发现我们Asp.net相关的SDK

在一番百度和一顿操作终于让我找到啦！看到没，只能说隐藏的真深，而且还是历史版本的，但是不管怎么样我们还是找到啦

找到C#的SDK,下载下来（附上C#版本SDK的下载地址 C# SDK github项目下载地址）然后按照SDK中提供的方法，就可以成功上传！

然而并没有这么简单，当我们使用SDK中的方法的时候发现，SDK中的方法只适用于，绝对路径地址的文件上传！也就是并不满足我们ASP.Net中使用文件域上传文件。此时我们只有对方法进行改造！

附上改造过后代码：


 /// <summary>
    /// 文件流上传
    /// 说明: 酷客多小程序
    /// 其中分片上传使用SliceUploadInit SliceUploadData SliceUploadFinihs
    /// </summary>
    /// <param name="bucketName">bucket名称</param>
    /// <param name="remotePath">远程文件路径</param>
    /// <param name="localPath">本地文件路径</param>
    /// <param name="parameterDic">参数Dictionary</param>
    /// <returns></returns>
    public string UploadFile(string bucketName, string remotePath, Stream file, string filename,Dictionary<string, string> parameterDic = null)
    {
      if (remotePath.EndsWith("/"))
      {
        return constructResult(ERRORCode.ERROR_CODE_PARAMETER_ERROE, "file path can not end with '/'");
      }
      string bizAttribute = "";
      if (parameterDic != null && parameterDic.ContainsKey(CosParameters.PARA_BIZ_ATTR))
        bizAttribute = parameterDic[CosParameters.PARA_BIZ_ATTR];
      int insertOnly = 1;
      if (parameterDic != null && parameterDic.ContainsKey(CosParameters.PARA_INSERT_ONLY))
      {
        try
        {
          insertOnly = Int32.Parse(parameterDic[CosParameters.PARA_INSERT_ONLY]);
        }
        catch (Exception e)
        {
          Console.WriteLine(e.Message);
          return constructResult(ERRORCode.ERROR_CODE_PARAMETER_ERROE, "parameter insertOnly value invalidate");
        }
      }
      return Upload(bucketName, remotePath, file, filename, bizAttribute, insertOnly);
    }
    /// <summary>
    /// 单个文件上传
    /// 说明: 酷客多小程序
    /// <param name="bucketName">bucket名称</param>
    /// <param name="remotePath">远程文件路径</param>
    /// <param name="localPath">本地文件路径</param>
    /// <param name="biz_attr">biz_attr属性</param>
    /// <param name="insertOnly">同名文件是否覆盖</param>
    /// <returns></returns>
    public string Upload(string bucketName, string remotePath, Stream file,string filename,
                 string bizAttribute = "", int insertOnly = 1)
    {
      var url = generateURL(bucketName, remotePath);
      var sha1 = SHA1.GetFileSHA1(file);
      var data = new Dictionary<string, object>();
      data.Add("op", "upload");
      data.Add("sha", sha1);
      data.Add("biz_attr", bizAttribute);
      data.Add("insertOnly", insertOnly);
      var expired = getExpiredTime();
      var sign = Sign.Signature(appId, secretId, secretKey, expired, bucketName);
      var header = new Dictionary<string, string>();
      header.Add("Authorization", sign);
      return httpRequest.SendRequest(url, ref data, HttpMethod.Post, ref header, timeOut, file, filename);
    }
    #region 直接上传文件流
    public string SendRequest(string url, ref Dictionary<string, object> data, HttpMethod requestMethod,
    ref Dictionary<string, string> header, int timeOut, Stream file,string filename, long offset = -1, int sliceSize = 0)
    {
      try
      {
        //Console.WriteLine("url:" + url);
        System.Net.ServicePointManager.Expect100Continue = false;
        if (requestMethod == HttpMethod.Get)
        {
          var paramStr = "";
          foreach (var key in data.Keys)
          {
            paramStr += string.Format("{0}={1}&", key, HttpUtility.UrlEncode(data[key].ToString()));
          }
          paramStr = paramStr.TrimEnd('&');
          url += (url.EndsWith("?") ? "&" : "?") + paramStr;
        }
        request = (HttpWebRequest)HttpWebRequest.Create(url);
        request.Accept = CosDefaultValue.ACCEPT;
        request.KeepAlive = true;
        request.UserAgent = CosDefaultValue.USER_AGENT_VERSION;
        request.Timeout = timeOut;
        foreach (var key in header.Keys)
        {
          if (key == "Content-Type")
          {
            request.ContentType = header[key];
          }
          else
          {
            request.Headers.Add(key, header[key]);
          }
        }
        if (requestMethod == HttpMethod.Post)
        {
          request.Method = requestMethod.ToString().ToUpper();
          var memStream = new MemoryStream();
          if (header.ContainsKey("Content-Type") && header["Content-Type"] == "application/json")
          {
            var json = JsonConvert.SerializeObject(data);
            var jsonByte = Encoding.GetEncoding("utf-8").GetBytes(json.ToString());
            memStream.Write(jsonByte, 0, jsonByte.Length);
          }
          else
          {
            var boundary = "---------------" + DateTime.Now.Ticks.ToString("x");
            var beginBoundary = Encoding.ASCII.GetBytes("\r\n--" + boundary + "\r\n");
            var endBoundary = Encoding.ASCII.GetBytes("\r\n--" + boundary + "--\r\n");
            request.ContentType = "multipart/form-data; boundary=" + boundary;
            var strBuf = new StringBuilder();
            foreach (var key in data.Keys)
            {
              strBuf.Append("\r\n--" + boundary + "\r\n");
              strBuf.Append("Content-Disposition: form-data; name=\"" + key + "\"\r\n\r\n");
              strBuf.Append(data[key].ToString());
            }
            var paramsByte = Encoding.GetEncoding("utf-8").GetBytes(strBuf.ToString());
            memStream.Write(paramsByte, 0, paramsByte.Length);
            memStream.Write(beginBoundary, 0, beginBoundary.Length);
            var fileStream = file;
            const string filePartHeader =
              "Content-Disposition: form-data; name=\"fileContent\"; filename=\"{0}\"\r\n" +
              "Content-Type: application/octet-stream\r\n\r\n";
            var headerText = string.Format(filePartHeader, filename);
            var headerbytes = Encoding.UTF8.GetBytes(headerText);
            memStream.Write(headerbytes, 0, headerbytes.Length);
            if (offset == -1)
            {
              var buffer = new byte[1024];
              int bytesRead;
              while ((bytesRead = fileStream.Read(buffer, 0, buffer.Length)) != 0)
              {
                memStream.Write(buffer, 0, bytesRead);
              }
            }
            else
            {
              var buffer = new byte[sliceSize];
              int bytesRead;
              fileStream.Seek(offset, SeekOrigin.Begin);
              bytesRead = fileStream.Read(buffer, 0, buffer.Length);
              memStream.Write(buffer, 0, bytesRead);
            }
            fileStream.Close();
            memStream.Write(endBoundary, 0, endBoundary.Length);
          }
          request.ContentLength = memStream.Length;
          var requestStream = request.GetRequestStream();
          memStream.Position = 0;
          var tempBuffer = new byte[memStream.Length];
          memStream.Read(tempBuffer, 0, tempBuffer.Length);
          memStream.Close();
          requestStream.Write(tempBuffer, 0, tempBuffer.Length);
          requestStream.Close();
          //Console.WriteLine(strBuf.ToString());
        }
        //Console.WriteLine(request.ContentType.ToString());
        var response = request.GetResponse();
        using (var s = response.GetResponseStream())
        {
          var reader = new StreamReader(s, Encoding.UTF8);
          return reader.ReadToEnd();
        }
      }
      catch (WebException we)
      {
        if (we.Status == WebExceptionStatus.ProtocolError)
        {
          using (var s = we.Response.GetResponseStream())
          {
            var reader = new StreamReader(s, Encoding.UTF8);
            return reader.ReadToEnd();
          }
        }
        else
        {
          throw we;
        }
      }
      catch (Exception e)
      {
        throw e;
      }
    }