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从ASP.NET MVC2向iPhone提供视频文件

video-streaming asp.net-mvc iphone

jocull · 技术社区 · 14 年前

我正在尝试将ASP.NET MVC的视频文件提供给iPhone客户端。视频格式正确,如果我把它放在一个可公开访问的web目录中,它可以正常工作。

我读到的核心问题是,iPhone要求你有一个可以随时下载简历的下载环境,允许你通过HTTP头过滤字节范围。我想这是为了让用户可以跳过视频。

当用MVC服务文件时,这些标题不存在。我试过模仿它,但没有运气。我们这里有IIS6,我根本不能做很多头球操作。ASP.NET会抱怨我说 此操作需要IIS集成管道模式。 "

升级不是一个选项,我不允许将文件移动到公共web共享。我觉得我们的环境有限,但我仍在寻找解决办法。

这里是一些我试图做的简单代码。。。

public ActionResult Mobile(string guid = "x")
{
    guid = Path.GetFileNameWithoutExtension(guid);
    apMedia media = DB.apMedia_GetMediaByFilename(guid);
    string mediaPath = Path.Combine(Transcode.Swap_MobileDirectory, guid + ".m4v");

    if (!Directory.Exists(Transcode.Swap_MobileDirectory)) //Make sure it's there...
        Directory.CreateDirectory(Transcode.Swap_MobileDirectory);

    if(System.IO.File.Exists(mediaPath))
        return base.File(mediaPath, "video/x-m4v");

    return Redirect("~/Error/404");
}

http://dotnetslackers.com/articles/aspnet/Range-Specific-Requests-in-ASP-NET.aspx

下面是一个工作的HTTP响应头示例:

Date    Mon, 08 Nov 2010 17:02:38 GMT
Server  Apache
Last-Modified   Mon, 08 Nov 2010 17:02:13 GMT
Etag    "14e78b2-295eff-4cd82d15"
Accept-Ranges   bytes
Content-Length  2711295
Content-Range   bytes 0-2711294/2711295
Keep-Alive  timeout=15, max=100
Connection  Keep-Alive
Content-Type    text/plain

下面是一个没有的例子(这是来自.NET的)

Server  ASP.NET Development Server/10.0.0.0
Date    Mon, 08 Nov 2010 18:26:17 GMT
X-AspNet-Version    4.0.30319
X-AspNetMvc-Version 2.0
Content-Range   bytes 0-2711294/2711295
Cache-Control   private
Content-Type    video/x-m4v
Content-Length  2711295
Connection  Close

4 回复 | 直到 14 年前

Erik Noren 14 年前

更新:现在是 project on CodePlex

好吧,我在本地的测试站工作,我可以把视频流到我的iPad上。它有点脏,因为它比我预期的要难一点,现在它工作了,我现在没有时间清理它。关键部位:

操作筛选器:

public class ByteRangeRequest : FilterAttribute, IActionFilter
{
    protected string RangeStart { get; set; }
    protected string RangeEnd { get; set; }

    public ByteRangeRequest(string RangeStartParameter, string RangeEndParameter)
    {
        RangeStart = RangeStartParameter;
        RangeEnd = RangeEndParameter;
    }

    public void OnActionExecuting(ActionExecutingContext filterContext)
    {
        if (filterContext == null)
            throw new ArgumentNullException("filterContext");

        if (!filterContext.ActionParameters.ContainsKey(RangeStart))
            filterContext.ActionParameters.Add(RangeStart, null);
        if (!filterContext.ActionParameters.ContainsKey(RangeEnd))
            filterContext.ActionParameters.Add(RangeEnd, null);

        var headerKeys = filterContext.RequestContext.HttpContext.Request.Headers.AllKeys.Where(key => key.Equals("Range", StringComparison.InvariantCultureIgnoreCase));
        Regex rangeParser = new Regex(@"(\d+)-(\d+)", RegexOptions.Compiled);

        foreach(string headerKey in headerKeys)
        {
            string value = filterContext.RequestContext.HttpContext.Request.Headers[headerKey];
            if (!string.IsNullOrEmpty(value))
            {
                if (rangeParser.IsMatch(value))
                {
                    Match match = rangeParser.Match(value);

                    filterContext.ActionParameters[RangeStart] = int.Parse(match.Groups[1].ToString());
                    filterContext.ActionParameters[RangeEnd] = int.Parse(match.Groups[2].ToString());
                    break;
                }
            }
        }
    }

    public void OnActionExecuted(ActionExecutedContext filterContext)
    {
    }
}

public class ContentRangeResult : FileStreamResult
{
    public int StartIndex { get; set; }
    public int EndIndex { get; set; }
    public long TotalSize { get; set; }
    public DateTime LastModified { get; set; }

    public FileStreamResult(int startIndex, int endIndex, long totalSize, DateTime lastModified, string contentType, Stream fileStream)
        : base(fileStream, contentType)
    {
        StartIndex = startIndex;
        EndIndex = endIndex;
        TotalSize = totalSize;
        LastModified = lastModified;
    }

    public override void ExecuteResult(ControllerContext context)
    {
        if (context == null)
            throw new ArgumentNullException("context");

        HttpResponseBase response = context.HttpContext.Response;
        response.ContentType = this.ContentType;
        response.AddHeader(HttpWorkerRequest.GetKnownResponseHeaderName(HttpWorkerRequest.HeaderContentRange), string.Format("bytes {0}-{1}/{2}", StartIndex, EndIndex, TotalSize));
        response.StatusCode = 206;

        WriteFile(response);
    }

    protected override void WriteFile(HttpResponseBase response)
    {
        Stream outputStream = response.OutputStream;
        using (this.FileStream)
        {
            byte[] buffer = new byte[0x1000];
            int totalToSend = EndIndex - StartIndex;
            int bytesRemaining = totalToSend;
            int count = 0;

            FileStream.Seek(StartIndex, SeekOrigin.Begin);

            while (bytesRemaining > 0)
            {
                if (bytesRemaining <= buffer.Length)
                    count = FileStream.Read(buffer, 0, bytesRemaining);
                else
                    count = FileStream.Read(buffer, 0, buffer.Length);

                outputStream.Write(buffer, 0, count);
                bytesRemaining -= count;
            }
        }
    }      
}

我的MVC行动:

[ByteRangeRequest("StartByte", "EndByte")]
public FileStreamResult NextSegment(int? StartByte, int? EndByte)
{
    FileStream contentFileStream = System.IO.File.OpenRead(@"C:\temp\Gets.mp4");
    var time = System.IO.File.GetLastWriteTime(@"C:\temp\Gets.mp4");
    if (StartByte.HasValue && EndByte.HasValue)
        return new ContentRangeResult(StartByte.Value, EndByte.Value, contentFileStream.Length, time, "video/x-m4v", contentFileStream);

    return new ContentRangeResult(0, (int)contentFileStream.Length, contentFileStream.Length, time, "video/x-m4v", contentFileStream);
}

我真的希望这能有帮助。我花了很多时间在这上面!有一件事你可能想试试,就是把碎片去掉,直到它再次断裂。很高兴看到ETag的内容、修改日期等是否可以删除。我只是现在没有时间。

Erik Noren 14 年前

我试图寻找一个现有的扩展,但我没有立即找到一个(也许我的搜索FU是弱的。)

我现在的想法是你需要上两门新课。

首先,创建一个继承自 ActionMethodSelectorAttribute HttpGet , HttpPost ,等等。在这个类中,您将重写 IsValidForRequest . 在该方法中,检查头以查看是否请求了范围。现在可以使用此属性修饰控制器中的方法,当某人被请求成为流的一部分(iOS、Silverlight等)时,将调用该方法

ActionResult 或者也许 FileResult 并覆盖 ExecuteResult

看一看路 FileContentResult 实现以查看如何访问上下文的 HttpResponse 对象来更改标题。

看一看看看它是如何实现对 . 源代码可以在CodePlex上找到,也可以像我刚才那样使用Reflector。

您可以使用此信息进行更多搜索,看看是否有人已经创建了此自定义已经。

作为参考,这里是AcceptVerbs属性的外观:

public override bool IsValidForRequest(ControllerContext controllerContext, MethodInfo methodInfo)
{
    if (controllerContext == null)
    {
        throw new ArgumentNullException("controllerContext");
    }
    string httpMethodOverride = controllerContext.HttpContext.Request.GetHttpMethodOverride();
    return this.Verbs.Contains<string>(httpMethodOverride, StringComparer.OrdinalIgnoreCase);
}

下面是FileResult的样子。注意AddHeader的用法:

public override void ExecuteResult(ControllerContext context)
{
    if (context == null)
    {
        throw new ArgumentNullException("context");
    }
    HttpResponseBase response = context.HttpContext.Response;
    response.ContentType = this.ContentType;
    if (!string.IsNullOrEmpty(this.FileDownloadName))
    {
        string headerValue = ContentDispositionUtil.GetHeaderValue(this.FileDownloadName);
        context.HttpContext.Response.AddHeader("Content-Disposition", headerValue);
    }
    this.WriteFile(response);
}

public class ContentRangeResult : FileStreamResult
{
    public int StartIndex { get; set; }
    public int EndIndex { get; set; }
    public int TotalSize { get; set; }

    public ContentRangeResult(int startIndex, int endIndex, string contentType, Stream fileStream)
        :base(fileStream, contentType)
    {
        StartIndex = startIndex;
        EndIndex = endIndex;
        TotalSize = endIndex - startIndex;
    }

    public ContentRangeResult(int startIndex, int endIndex, string contentType, string fileDownloadName, Stream fileStream)
        : base(fileStream, contentType)
    {
        StartIndex = startIndex;
        EndIndex = endIndex;
        TotalSize = endIndex - startIndex;
        FileDownloadName = fileDownloadName;
    }

    public override void ExecuteResult(ControllerContext context)
    {
        if (context == null)
        {
            throw new ArgumentNullException("context");
        }

        HttpResponseBase response = context.HttpContext.Response;
        if (!string.IsNullOrEmpty(this.FileDownloadName))
        {
            System.Net.Mime.ContentDisposition cd = new System.Net.Mime.ContentDisposition() { FileName = FileDownloadName };
            context.HttpContext.Response.AddHeader("Content-Disposition", cd.ToString());
        }

        context.HttpContext.Response.AddHeader("Accept-Ranges", "bytes");
        context.HttpContext.Response.AddHeader("Content-Range", string.Format("bytes {0}-{1}/{2}", StartIndex, EndIndex, TotalSize));
        //Any other headers?


        this.WriteFile(response);
    }

    protected override void WriteFile(HttpResponseBase response)
    {
        Stream outputStream = response.OutputStream;
        using (this.FileStream)
        {
            byte[] buffer = new byte[0x1000];
            int totalToSend = EndIndex - StartIndex;
            int bytesRemaining = totalToSend;
            int count = 0;

            while (bytesRemaining > 0)
            {
                if (bytesRemaining <= buffer.Length)
                    count = FileStream.Read(buffer, 0, bytesRemaining);
                else
                    count = FileStream.Read(buffer, 0, buffer.Length);

                outputStream.Write(buffer, 0, count);

                bytesRemaining -= count;
            }
        }
    }
}

像这样使用:

return new ContentRangeResult(50, 100, "video/x-m4v", "SomeOptionalFileName", contentFileStream);

Wyatt Barnett 14 年前

你能搬出MVC吗?这是一个系统抽象让你大吃一惊的例子,但是一个普通的jane ihttfandler应该有更多的选择。

尽管如此,在您实现自己的流媒体服务器之前,您可能最好购买或租赁一台流媒体服务器。. .

-1

David Martinez 14 年前

工作的标题将内容类型设置为text/plain,这是正确的还是打字错误?.

Response.Headers.Add(...)