/BlogEngine/BlogEngine.NET/App_Code/Extensions/SendPings.cs

#region using



using System;

using System.Threading;



using BlogEngine.Core;

using BlogEngine.Core.Ping;

using BlogEngine.Core.Web.Controls;

using BlogEngine.Core.Web.Extensions;

using System.Collections.Specialized;

using BlogEngine.Core.Providers;



#endregion



/// <summary>

/// Pings all the ping services specified on the 

///     PingServices admin page and send track- and pingbacks

/// </summary>

[Extension("Pings all the ping services specified on the PingServices admin page and send track- and pingbacks", "1.3",

    "BlogEngine.NET")]

public class SendPings

{

    #region Constructors and Destructors



    /// <summary>

    /// Initializes static members of the <see cref="SendPings"/> class. 

    ///     Hooks up an event handler to the Post.Saved event.

    /// </summary>

    static SendPings()

    {

        Post.Saved += PostSaved;

        Page.Saved += PostSaved;

    }



    #endregion



    #region Methods



    /// <summary>

    /// Executes the pings from the new thread.

    /// </summary>

    /// <param name="item">

    /// The publishable item.

    /// </param>

    /// <param name="itemUrl">

    /// The item Url.

    /// </param>

    private static void Ping(IPublishable item, Uri itemUrl)

    {

        try

        {

            Thread.Sleep(2000);



            // Ping the specified ping services.

            PingService.Send(itemUrl);



            // Send trackbacks and pingbacks.

            if (!BlogSettings.Instance.EnableTrackBackSend && !BlogSettings.Instance.EnablePingBackSend)

            {

                return;

            }



            if (item.Content.ToUpperInvariant().Contains("\"HTTP"))

            {

                Manager.Send(item, itemUrl);

            }

        }

        catch (Exception)

        {

            // We need to catch this exception so the application doesn't get killed.

        }

    }



    /// <summary>

    /// Handles the Saved event of the Post control.

    /// Sends the pings in a new thread.

    ///     <remarks>

    /// It opens a new thread and executes the pings from there,

    ///         because it takes some time to complete.

    ///     </remarks>

    /// </summary>

    /// <param name="sender">The source of the event.</param>

    /// <param name="e">The <see cref="BlogEngine.Core.SavedEventArgs"/> instance containing the event data.</param>

    private static void PostSaved(object sender, SavedEventArgs e)

    {

        if (!ExtensionManager.ExtensionEnabled("SendPings"))

            return;



        if (e.Action == SaveAction.None || e.Action == SaveAction.Delete)

            return;



        var item = (IPublishable)sender;

        if (!item.IsVisibleToPublic)

            return;

        

        var url = item.AbsoluteLink;



        // Need blogSettings to pass to Ping since the current blog instance won't

        // be detectable once in a BG thread.

        Guid blogId = Blog.CurrentInstance.Id;

        ThreadPool.QueueUserWorkItem(state =>

            {

                // because HttpContext is not available within this BG thread

                // needed to determine the current blog instance,

                // set override value here.

                Blog.InstanceIdOverride = blogId;



                Ping(item, url);

            });

    }



    #endregion

}