在EpiServer 8中，如何扩展预定的发布事件？

Question

我正在使用EpiServer 8，并需要在保存计划发布时执行自定义API调用。目前，我能够通过初始化模块捕获即时发布事件，如下所示：

[InitializableModule]
[ModuleDependency(typeof(EPiServer.Web.InitializationModule))]
public class ContentEventInitializer : IInitializableModule
{
    public void Initialize(InitializationEngine initializationEngine)
    {
        var events = ServiceLocator.Current.GetInstance<IContentEvents>();
        events.PublishingContent += EventsPublishingContent;
    }

    public void Preload(string[] parameters)
    {
    }

    public void Uninitialize(InitializationEngine initializationEngine)
    {
        var events = ServiceLocator.Current.GetInstance<IContentEvents>();
        events.PublishingContent -= EventsPublishingContent;
    }

    private void EventsPublishingContent(object sender, ContentEventArgs contentEventArgs)
    {
        // Tell our API that maintenance started.
    }
}

当编辑器立即发布内容时，上面的EventsPublishingContent事件可以工作。该方法的Visual断点将被成功击中。但是，当站点编辑器选择“计划发布”时，它不会被执行。

当编辑器正在查看“发布计划”对话框并选择"Schedule“按钮时，我想捕获以下内容并将其发送到我们的API：

• “发布更改”值。
• 即将出版的网页。

做这件事的正确方法是什么？谢谢。

Answer 1

下面是我运行的解决方案中的关键部分。最后，我在来自IContentEvents的十几个潜在事件中插入了断点，并分离出了两个对我的目的有用的事件。不幸的是，我不得不从EpiServer数据库中获取预定的发布时间戳。代码中提供了一些TODO注释，这只是为了简化答案。

代码中的注释是根据我的观察得出的。我不是EpiServer大师。

using EPiServer;
using EPiServer.Core;
using EPiServer.Framework;
using EPiServer.Framework.Initialization;
using EPiServer.ServiceLocation;

namespace MySite.Helpers
{
    [InitializableModule]
    [ModuleDependency(typeof(EPiServer.Web.InitializationModule))]
    public class ContentEventInitializer : IInitializableModule
    {
        public void Initialize(InitializationEngine initializationEngine)
        {
            var events = ServiceLocator.Current.GetInstance<IContentEvents>();
            events.CheckedInContent += checkedInContent;
            events.PublishedContent += publishedContent;   
        }

        public void Uninitialize(InitializationEngine initializationEngine)
        {
            var events = ServiceLocator.Current.GetInstance<IContentEvents>();
            events.CheckedInContent -= checkedInContent;
            events.PublishedContent -= publishedContent;   
        }

        /// <summary>
        /// Occurs when a version of a content item has been checked in.
        /// </summary>
        /// <remarks>
        /// This is called after a scheduled publish gets saved.  It's not called after an immediate publish.
        /// Useful for executing custom events following a scheduled publish.  When this event occurs,
        /// you can fetch the publish timestamp from dbo.tblWorkContent.DelayPublishUntil.
        /// Prior to this event the DelayPublishUntil value will be NULL.
        /// </remarks>
        public static void checkedInContent(object sender, ContentEventArgs contentEventArgs)
        {
            // Fetch timestamp from dbo.tblWorkContent.DelayPublishUntil.
            ConnectInfo connectInfo = new ConnectInfo("MyEpiServerDatabase");
            PlannedMaintenanceInfo plannedMaintenanceInfo = new PlannedMaintenanceInfo(ref connectInfo, contentEventArgs.Content.ContentLink.WorkID);
            connectInfo = null;
            // The PlannedMaintenanceInfo method above uses the following SQL query:
            //    string query = string.Format("SELECT URLSegment, DelayPublishUntil FROM tblWorkContent WHERE pkId = {0}", WorkID);

            // TODO: Notify API about this planned maintenance window.
        }

        /// <summary>
        /// Occurs when a content item or a version of a content item has been published.
        /// </summary>
        /// <remarks>
        /// This is called after an immediate publish.  It's not called after a scheduled publish gets saved.
        /// Useful for executing custom events following an immediate publish.
        /// </remarks>
        public void publishedContent(object sender, ContentEventArgs contentEventArgs)
        {
            // TODO: Notify API that an immediate maintenance window has started.
        }
    }
}

为了简洁起见，省略了数据检索代码和其他移动部件。如果您正在阅读这篇文章，我想您应该知道如何获取数据，并且有自己的首选项或框架。我编写的实际SQL查询在checkedInContent方法的注释中。所以你可以拿着它在你自己的数据库里运行。重要的是确保将WorkID传递给查询。ID来自contentEventArgs.Content.ContentLink.WorkID。

我希望EpiServer公开这个时间戳值，这个时间戳值最终在表单提交过程中保存到tblWorkContent.DelayPublishUntil。这样就不需要从数据库中获取值了。这样就可以更容易地以一种更通用的方式重用它，在这里，我们不需要提供数据库连接字符串来提取时间戳。如果这个价值暴露在某个财产中，而我只是错过了它，请告诉我。

我希望这段代码能帮上忙。

Answer 2

当使用“发布计划”时，页面将由计划作业发布，我不认为任何事件都会由此触发，至少看起来不像，这里有更多信息：http://world.episerver.com/blogs/Petra-Liljecrantz/Dates/2016/3/differences-between-scheduled-publish-and-normal-publish/