CDNMediaProvider.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using NTTData.SitecoreCDN.Configuration;
using Sitecore.Resources.Media;
using NTTData.SitecoreCDN.Switchers;
using Sitecore.Text;

namespace NTTData.SitecoreCDN.Providers
{
    /// <summary>
    /// Extends MediaProvider to allow for CDN url replacement at the Provider level
    /// </summary>
    public class CDNMediaProvider : MediaProvider
    {
        /// <summary>
        /// If CDN is enabled for this request, replace the outgoing media url with the cdn version
        /// </summary>
        /// <param name="item"></param>
        /// <param name="options"></param>
        /// <returns></returns>
        public override string GetMediaUrl(Sitecore.Data.Items.MediaItem item, MediaUrlOptions options)
        {
            if (CDNSettings.Enabled)
            {
                string hostname = CDNManager.GetCDNHostName();
                string url = base.GetMediaUrl(item, options);

                bool shouldReplace = !string.IsNullOrEmpty(hostname) && // cdnHostname exists for site
                    Sitecore.Context.PageMode.IsNormal;  // PageMode is normal

                bool dontReplace = !CDNManager.IsMediaPubliclyAccessible(item) ||  // media is publicly accessible
                    CDNManager.IsMediaAnalyticsTracked(item); // media is analytics tracked

                CDNUrlState contextState = CDNUrlSwitcher.CurrentValue;

                if (contextState == CDNUrlState.Enabled)
                {
                    shouldReplace = true;
                }
                else if (contextState == CDNUrlState.Disabled)
                {
                    UrlString url2 = new UrlString(url);
                    url2[CDNManager.StopToken] = "1";
                    url = url2.ToString();
                    shouldReplace = false;
                }

                if (shouldReplace && !dontReplace) // media not DMS tracked
                {
                    return CDNManager.ReplaceMediaUrl(url, hostname);
                }
                else
                {
                    return url;
                }
            }
            return base.GetMediaUrl(item, options);
        }
    }
}