通过Asp.net Web Api访问第三方API的大文件下载

Question

我正在开发一套ASP.Net Web API，将第三方文档管理系统集成到现有的CMS中。第三方有一组API调用来启用此功能。我已经完成了大部分集成工作，但下载文档非常慢。这看起来是因为我打电话下载。该文件从第三方下载到Web服务器，然后从Web服务器下载到客户端。

出于安全原因，我试图避免直接调用第三方API。有没有办法让我的端点充当第三方API的代理。允许文件流直接传递给客户端吗？

    public static  HttpResponseMessage GetDocument(string docId, string docName)
                {

                    HttpResponseMessage result = new HttpResponseMessage(HttpStatusCode.OK);
                    var stream = getDocumentStream(docId, docName);

                    result.Content = new StreamContent(stream);
                    result.Content.Headers.ContentType =
                        new MediaTypeHeaderValue("application/octet-stream");
                    result.Content.Headers.Add("Content-Disposition", "attachment; filename=\"" + docName + "\"");


                    return result;
                }

 public static Stream getDocumentStream(string docId,string name)
        {
            var UriTemplate = ApiUri;
            var ParamTemplate = "name=" + name + "&documentId=" + docId;
            var userName = ConfigurationManager.AppSettings["EdeskUserName"];
            var passWord = ConfigurationManager.AppSettings["EdeskPWD"];
            return EDeskDataUtility.EdeskAPIDownload(UriTemplate, ParamTemplate, userName, passWord);

        }



         public static Stream DownloadFile(string URI, string Parameters)
                {
                    WebResponse resp = GetURIResponse(URI, Parameters);
                    if (resp == null) return null;
                    return resp.GetResponseStream();

                }



                public static System.Net.WebResponse GetURIResponse(string URI, string Parameters)
                {
                    System.Net.WebRequest req = System.Net.WebRequest.Create(URI);
                    req.ContentType = "application/x-www-form-urlencoded";
                    req.Method = "POST";

                    //We need to count how many bytes we're sending. Post'ed Faked Forms should be name=value&
                    byte[] bytes = System.Text.Encoding.ASCII.GetBytes(Parameters);
                    req.ContentLength = bytes.Length;
                    System.IO.Stream os = req.GetRequestStream();
                    os.Write(bytes, 0, bytes.Length); //Push it out there
                    os.Close();
                   var resp = req.GetResponse();
                    return resp;
                }