/BlogEngine/DotNetSlave.BusinessLogic/Web/HttpHandlers/SiteMap.cs

namespace BlogEngine.Core.Web.HttpHandlers

{

    using System;

    using System.Globalization;

    using System.Linq;

    using System.Web;

    using System.Xml;



    /// <summary>

    /// A blog sitemap suitable for Google Sitemap as well as

    ///     other big search engines such as MSN/Live, Yahoo and Ask.

    /// </summary>

    public class SiteMap : IHttpHandler

    {

        #region Properties



        /// <summary>

        ///     Gets a value indicating whether another request can use the <see cref = "T:System.Web.IHttpHandler"></see> instance.

        /// </summary>

        /// <value></value>

        /// <returns>true if the <see cref = "T:System.Web.IHttpHandler"></see> instance is reusable; otherwise, false.</returns>

        public bool IsReusable

        {

            get

            {

                return false;

            }

        }



        #endregion



        #region Implemented Interfaces



        #region IHttpHandler



        /// <summary>

        /// Enables processing of HTTP Web requests by a custom HttpHandler that 

        ///     implements the <see cref="T:System.Web.IHttpHandler"></see> interface.

        /// </summary>

        /// <param name="context">

        /// An <see cref="T:System.Web.HttpContext"></see> 

        ///     object that provides references to the intrinsic server objects 

        ///     (for example, Request, Response, Session, and Server) used to service HTTP requests.

        /// </param>

        public void ProcessRequest(HttpContext context)

        {

            using (var writer = XmlWriter.Create(context.Response.OutputStream))

            {

                writer.WriteStartElement("urlset", "http://www.google.com/schemas/sitemap/0.84");



                // Posts

                foreach (var post in Post.Posts.Where(post => post.IsVisibleToPublic))

                {

                    writer.WriteStartElement("url");

                    writer.WriteElementString("loc", post.AbsoluteLink.ToString());

                    writer.WriteElementString(

                        "lastmod", post.DateModified.ToString("yyyy-MM-dd", CultureInfo.InvariantCulture));

                    writer.WriteElementString("changefreq", "monthly");

                    writer.WriteEndElement();

                }



                // Pages

                foreach (var page in Page.Pages.Where(page => page.IsVisibleToPublic))

                {

                    writer.WriteStartElement("url");

                    writer.WriteElementString("loc", page.AbsoluteLink.ToString());

                    writer.WriteElementString(

                        "lastmod", page.DateModified.ToString("yyyy-MM-dd", CultureInfo.InvariantCulture));

                    writer.WriteElementString("changefreq", "monthly");

                    writer.WriteEndElement();

                }



                // Removed for SEO reasons

                //// Archive

                // writer.WriteStartElement("url");

                // writer.WriteElementString("loc", Utils.AbsoluteWebRoot.ToString() + "archive.aspx");

                // writer.WriteElementString("lastmod", DateTime.Now.ToString("yyyy-MM-dd", System.Globalization.CultureInfo.InvariantCulture));

                // writer.WriteElementString("changefreq", "daily");

                // writer.WriteEndElement();



                // Contact

                writer.WriteStartElement("url");

                writer.WriteElementString("loc", string.Format("{0}contact.aspx", Utils.AbsoluteWebRoot));

                writer.WriteElementString("lastmod", DateTime.Now.ToString("yyyy-MM-dd", CultureInfo.InvariantCulture));

                writer.WriteElementString("changefreq", "monthly");

                writer.WriteEndElement();



                // Blog

                if (Page.GetFrontPage() != null)

                {

                    writer.WriteStartElement("url");

                    writer.WriteElementString("loc", string.Format("{0}blog.aspx", Utils.AbsoluteWebRoot));

                    writer.WriteElementString(

                        "lastmod", DateTime.Now.ToString("yyyy-MM-dd", CultureInfo.InvariantCulture));

                    writer.WriteElementString("changefreq", "daily");

                    writer.WriteEndElement();

                }



                writer.WriteEndElement();

            }



            context.Response.ContentType = "text/xml";

        }



        #endregion



        #endregion

    }

}