asp.net-mvc-3 - 如何使用 .net 将文件上传到 RackSpace 云文件？

Question

我想使用 RackSpace 的 CDN(云文件)来存储我的静态内容。问题是我正在使用 ASP.NET MVC3 并且我还没有看到任何当前的工作示例来说明如何做到这一点。

我在网上看到了几个示例，但它们都是 RackSpace 不再支持的版本。您可以在他们的注释中确认:

http://www.rackspace.com/knowledge_center/article/sample-csharp-application-for-cloud-files

当您在 openstack.net 下查看 RackSpace 的 gitHub 帐户(他们的支持重定向到该项目)时，您会发现不支持将文件上传到 Cloud Files。您可以在"file"表下看到:

https://github.com/rackspace/openstack.net/wiki/Feature-Support

如何使用 C# 以编程方式将文件上传到 RackSpace 的云文件？

Answer 1

您是对的，目前 openstack.net 项目不支持 CloudFiles。该功能计划于本月晚些时候(4 月中旬)发布。如果您愿意，您仍然可以使用 csharp-cloudfiles ( https://github.com/rackerlabs/csharp-cloudfiles )，因为它仍然有效，它只是处于弃用状态，不会收到任何更新或错误修复。

但是，这是一个快速但不完善的控制台应用程序，它使用内置的 HttpWebRequest/Response 对象，应该可以帮助您入门，直到 openstack.net v1.1 发布。

class Program
{
    const string filePath = @"Path\FileName";
    const string myToken = "myToken";
    const string url = "Url/Container/FileName";

    static void Main(string[] args)
    {
        //Do();
        DoAsync();
    }

    static void Do()
    {
        using (var fs = File.Open(filePath, FileMode.Open, FileAccess.Read))
        {
            UploadStream(new Uri(url), fs, myToken,
                (response) => Console.WriteLine("Upload Complete.  Status Code: {0} ({1})", response.StatusCode, response.StatusDescription));
        }

        Console.WriteLine("Done!");
        Console.ReadLine();
    }

    static void DoAsync()
    {
        IAsyncResult asyncRes;
        using (var fs = File.Open(filePath, FileMode.Open, FileAccess.Read))
        {
            asyncRes = UploadStreamAsync(new Uri(url), fs, myToken,
                (asyncResult) =>
                {
                    var request = (HttpWebRequest)asyncResult.AsyncState;
                    var response = (HttpWebResponse)request.EndGetResponse(asyncResult);
                    Console.WriteLine("Upload Complete.  Status Code: {0} ({1})", response.StatusCode, response.StatusDescription);
                });
        }

        asyncRes.AsyncWaitHandle.WaitOne();

        Console.WriteLine("Done!");
        Console.ReadLine();
    }

    static IAsyncResult UploadStreamAsync(Uri uri, Stream contents, string token, AsyncCallback resultCallback, int chunkSize = 8 * 1024)
    {
        var req = (HttpWebRequest)WebRequest.Create(uri);
        req.Headers.Add("X-Auth-Token", token);
        req.Method = "PUT";

        req.AllowWriteStreamBuffering = false;
        if (req.ContentLength == -1L)
            req.SendChunked = true;

        using (Stream stream = req.GetRequestStream())
        {
            var buffer = new byte[chunkSize];
            int count;
            while ((count = contents.Read(buffer, 0, chunkSize)) > 0)
            {
                stream.Write(buffer, 0, count);
            }
        }

        return req.BeginGetResponse(resultCallback, req);
    }

    static void UploadStream(Uri uri, Stream contents, string token, Action<HttpWebResponse> resultCallback, int chunkSize = 8 * 1024)
    {
        var req = (HttpWebRequest)WebRequest.Create(uri);
        req.Headers.Add("X-Auth-Token", token);
        req.Method = "PUT";

        req.AllowWriteStreamBuffering = false;
        if (req.ContentLength == -1L)
            req.SendChunked = true;

        using (Stream stream = req.GetRequestStream())
        {
            var buffer = new byte[chunkSize];
            int count;
            while ((count = contents.Read(buffer, 0, chunkSize)) > 0)
            {
                stream.Write(buffer, 0, count);
            }
        }

        using (var resp = req.GetResponse() as HttpWebResponse)
        {
            resultCallback(resp);
        }
    }
}

在上面的代码中，我同时提供了 Async 和 Synchronous 方法，因此您不需要两者，只需使用最适合您的方法即可。

如果您安装了 Http 客户端 NuGet 包 ( http://nuget.org/packages/Microsoft.Net.Http/2.0.20710.0 )，您也可以使用 HttpClient 库。这是一个示例:

static void UploadFileToRSCloud(string path, string filename)
{
    HttpClient client = new HttpClient();
    MemoryStream ms = new MemoryStream();

    client.DefaultRequestHeaders.TransferEncodingChunked = true;

    var filePath = 
    // Copy the data to the Resource Part 
    using (FileStream fileStream = new FileStream(filename, FileMode.Open, FileAccess.Read))
    {
        CopyStream(fileStream, ms);
    }// end:using(fileStream) - Close and dispose fileStream. 

    ms.Position = 0;
    StreamContent sc = new StreamContent(ms);

    client.DefaultRequestHeaders.Add("X-Auth-Token", "TOKEN HERE");

    var result = client.PutAsync( "UrlBase/Container/ChipperJones.jpg", sc);

    result.Wait();
}

private static void CopyStream(Stream source, Stream target)
{
    const int bufSize = 0x1000;
    byte[] buf = new byte[bufSize];
    int bytesRead = 0;
    while ((bytesRead = source.Read(buf, 0, bufSize)) > 0)
        target.Write(buf, 0, bytesRead);
}

希望对您有所帮助!