MIX09 Session Videos – How I Did It

On my last post I introduced the feeds I created to subscribe to Mix09 session videos.

In case someone is interested on how I did it, here it is:

<%@ WebHandler Language="C#" Class="mix09" %>
using System;
using System.IO;
using System.Web;
using System.Linq;
using System.Xml.Linq;
using System.Net;
using System.Xml;
public class mix09 : IHttpHandler, IHttpAsyncHandler
{
class WebClientOpenReadAsyncResult : IAsyncResult
{
private AsyncCallback callback;
    <span style="color: blue">public </span>WebClientOpenReadAsyncResult()
    {
        <span style="color: blue">this</span>.IsCompleted = <span style="color: blue">true</span>;
        <span style="color: blue">this</span>.CompletedSynchronously = <span style="color: blue">true</span>;
    }

    <span style="color: blue">public </span>WebClientOpenReadAsyncResult(<span style="color: #2b91af">AsyncCallback </span>callback)
    {
        <span style="color: blue">this</span>.callback = callback;
        <span style="color: blue">this</span>.IsCompleted = <span style="color: blue">false</span>;
        <span style="color: blue">this</span>.CompletedSynchronously = <span style="color: blue">false</span>;
    }

    <span style="color: blue">public object </span>AsyncState
    {
        <span style="color: blue">get </span>{ <span style="color: blue">return null</span>; }
    }

    <span style="color: blue">public bool </span>CompletedSynchronously { <span style="color: blue">get</span>; <span style="color: blue">private set</span>; }

    <span style="color: blue">public </span>System.Threading.<span style="color: #2b91af">WaitHandle </span>AsyncWaitHandle
    {
        <span style="color: blue">get </span>{ <span style="color: blue">throw new </span><span style="color: #2b91af">InvalidOperationException</span>(<span style="color: #a31515">&quot;ASP.NET should not use this property .&quot;</span>); }
    }

    <span style="color: blue">public bool </span>IsCompleted { <span style="color: blue">get</span>; <span style="color: blue">private set</span>; }

    <span style="color: blue">public </span><span style="color: #2b91af">Stream </span>Stream { <span style="color: blue">get</span>; <span style="color: blue">private set</span>; }

    <span style="color: blue">public void </span>Completed(<span style="color: blue">object </span>sender, <span style="color: #2b91af">OpenReadCompletedEventArgs </span>e)
    {
        <span style="color: blue">this</span>.IsCompleted = <span style="color: blue">true</span>;
        <span style="color: blue">this</span>.Stream = e.Result;
        <span style="color: blue">if </span>(<span style="color: blue">this</span>.callback != <span style="color: blue">null</span>)
        {
            <span style="color: blue">this</span>.callback(<span style="color: blue">this</span>);
        }
    }

}

<span style="color: blue">private static </span><span style="color: #2b91af">Uri </span>mixSessionsUri = <span style="color: blue">new </span><span style="color: #2b91af">Uri</span>(<span style="color: #a31515">&quot;http://sessions.visitmix.com/RSS&quot;</span>);

<span style="color: blue">private </span><span style="color: #2b91af">HttpContext </span>context;

<span style="color: blue">private string </span>type;

<span style="color: blue">#region </span>IHttpHandler Members

<span style="color: blue">public bool </span>IsReusable
{
    <span style="color: blue">get </span>{ <span style="color: blue">return true</span>; }
}

<span style="color: blue">public void </span>ProcessRequest(<span style="color: #2b91af">HttpContext </span>context)
{
    <span style="color: #2b91af">WebClient </span>wc = InitializeRequest(context);

    <span style="color: blue">if </span>(wc == <span style="color: blue">null</span>)
    {
        <span style="color: blue">return</span>;
    }

    OutputFeed(wc.OpenRead(mixSessionsUri));
}

<span style="color: blue">#endregion

#region </span>IHttpAsyncHandler Members

<span style="color: blue">public </span><span style="color: #2b91af">IAsyncResult </span>BeginProcessRequest(<span style="color: #2b91af">HttpContext </span>context, <span style="color: #2b91af">AsyncCallback </span>cb, <span style="color: blue">object </span>extraData)
{
    <span style="color: #2b91af">WebClient </span>wc = InitializeRequest(context);

    <span style="color: blue">if </span>(wc == <span style="color: blue">null</span>)
    {
        <span style="color: blue">return new </span><span style="color: #2b91af">WebClientOpenReadAsyncResult</span>();
    }

    <span style="color: #2b91af">WebClientOpenReadAsyncResult </span>ar = <span style="color: blue">new </span><span style="color: #2b91af">WebClientOpenReadAsyncResult</span>(cb);

    wc.OpenReadCompleted += ar.Completed;

    wc.OpenReadAsync(mixSessionsUri, extraData);

    <span style="color: blue">return </span>ar;
}

<span style="color: blue">public void </span>EndProcessRequest(<span style="color: #2b91af">IAsyncResult </span>result)
{
    <span style="color: #2b91af">Stream </span>stream = (result <span style="color: blue">as </span><span style="color: #2b91af">WebClientOpenReadAsyncResult</span>).Stream;

    <span style="color: blue">if </span>(stream != <span style="color: blue">null</span>)
    {
        OutputFeed(stream);
    }
}

<span style="color: blue">#endregion

private </span><span style="color: #2b91af">WebClient </span>InitializeRequest(<span style="color: #2b91af">HttpContext </span>context)
{
    <span style="color: blue">this</span>.context = context;
    <span style="color: blue">this</span>.type = context.Request.QueryString[<span style="color: #a31515">&quot;type&quot;</span>];

    <span style="color: blue">if </span>(<span style="color: blue">string</span>.IsNullOrEmpty(<span style="color: blue">this</span>.type))
    {
        <span style="color: blue">return null</span>;
    }

    <span style="color: #2b91af">WebClient </span>wc = <span style="color: blue">new </span><span style="color: #2b91af">WebClient</span>();
    wc.Headers[<span style="color: #2b91af">HttpRequestHeader</span>.UserAgent] = <span style="color: #a31515">&quot;Required User Agent&quot;</span>;
    <span style="color: blue">return </span>wc;
}

<span style="color: blue">private void </span>OutputFeed(<span style="color: #2b91af">Stream </span>source)
{
    <span style="color: #2b91af">XmlReader </span>feedReader = <span style="color: #2b91af">XmlReader</span>.Create(source);

    <span style="color: #2b91af">XDocument </span>feed = <span style="color: #2b91af">XDocument</span>.Load(feedReader);

    <span style="color: blue">var </span>rss = feed.Element(<span style="color: #a31515">&quot;rss&quot;</span>);
    <span style="color: blue">var </span>channel = rss.Element(<span style="color: #a31515">&quot;channel&quot;</span>);
    <span style="color: blue">var </span>title = channel.Element(<span style="color: #a31515">&quot;title&quot;</span>);

    title.Value = <span style="color: blue">string</span>.Format(<span style="color: #a31515">&quot;{0} ({1})&quot;</span>, title.Value, <span style="color: blue">this</span>.type.ToUpper());
    channel.Element(<span style="color: #a31515">&quot;link&quot;</span>).Value = <span style="color: #a31515">&quot;http://cli.gs/Mix09Sessions&quot;</span>;

    <span style="color: blue">foreach </span>(<span style="color: blue">var </span>item <span style="color: blue">in </span>channel.Elements(<span style="color: #a31515">&quot;item&quot;</span>))
    {
        <span style="color: blue">string </span>link = item.Element(<span style="color: #a31515">&quot;link&quot;</span>).Value;
        <span style="color: blue">string </span>session = link.Substring(link.LastIndexOf(<span style="color: #a31515">'/'</span>) + 1).ToLower();
        <span style="color: blue">string </span>enclosureUrl = <span style="color: blue">string</span>.Format(<span style="color: #a31515">&quot;http://mschannel9.vo.msecnd.net/o9/mix/09/{0}/{1}.wmv&quot;</span>, <span style="color: blue">this</span>.type.ToLower(), session);

        item.Add(
            <span style="color: blue">new </span><span style="color: #2b91af">XElement</span>(<span style="color: #a31515">&quot;enclosure&quot;</span>,
                <span style="color: blue">new </span><span style="color: #2b91af">XAttribute</span>(<span style="color: #a31515">&quot;url&quot;</span>, enclosureUrl)));
    }

    <span style="color: blue">this</span>.context.Response.Write(feed.ToString());

    <span style="color: blue">this</span>.context.Response.ContentType = <span style="color: #a31515">&quot;application/rss+xml&quot;</span>;

    <span style="color: #2b91af">HttpCachePolicy </span>cache = <span style="color: blue">this</span>.context.Response.Cache;
    cache.SetCacheability(<span style="color: #2b91af">HttpCacheability</span>.ServerAndPrivate);
    cache.SetExpires(<span style="color: #2b91af">DateTime</span>.Now.AddHours(1));
    cache.VaryByParams[<span style="color: #a31515">&quot;type&quot;</span>] = <span style="color: blue">true</span>;
    cache.SetValidUntilExpires(<span style="color: blue">true</span>);
}

}