Jason,

Any issues in the umbracolog? The latest version of Umbraco I have used is 7.2.4.

Regards

Ismail

yes, it's because you are binding to events on your ctor:

 ExamineManager.Instance.IndexProviderCollection["ExternalIndexer"].GatheringNodeData += ExamineEvents_GatheringNodeData;
 ExamineManager.Instance.IndexProviderCollection["AxumIndexer"].GatheringNodeData += ExamineEvents_GatheringNodeData;

You should never really do that. ApplicationBase is super old and shouldn't be used anymore

You should move all of that logic to your AppEvents and bind to events inside of started.

...basically you are binding to events before Umbraco boots. This might have 'worked' before but was causing other issues.

On another note, you will suffer performance penalties for the way you are coding your event handler:

This call:

 IEnumerable<IContent> ancestors = cs.GetAncestors(nodeId);

Should be:

 IEnumerable<IContent> ancestors = cs.GetAncestors(nodeId).ToArray();

Because you are re-iterating of this IEnumerable a whole lot of times! especially with the use of Count() and First(). Without ToArray(), your call to Count() will re-iterate the entire ancestors collection... behind the scenes you don't know what that is doing! I suggest using Resharper, it will tell you if you are re-iterating IEnumerable collections which shouldn't be done.

Also, I would very strongly suggest that you don't ever swallow Exceptions. You should at least log the Exception:

LogHelper.Error<AppEvents >("Write something about why you felt the need to have a try catch", ex);

If you are just swallowing exceptions (ever), you will never know why things are not working as you intended.

Okay so what I have now done is the following:

public class AppEvents : IApplicationEventHandler
    {
        public void OnApplicationInitialized(UmbracoApplicationBase umbracoApplication, ApplicationContext applicationContext)
        {

        }

        public void OnApplicationStarting(UmbracoApplicationBase umbracoApplication, ApplicationContext applicationContext)
        {
        }

        public void OnApplicationStarted(UmbracoApplicationBase umbracoApplication, ApplicationContext applicationContext)
        {
            var helper = new UmbracoHelper(UmbracoContext.Current);
            ExamineManager.Instance.IndexProviderCollection["AxumIndexer"].GatheringNodeData
                += (sender, e) => AppEvents.GatheringContentData(sender, e, helper);
        }

        public static void GatheringContentData(object sender, IndexingNodeDataEventArgs e, UmbracoHelper helper)
        {
            AddToContentsField(e);
        }

        private static void AddToContentsField(IndexingNodeDataEventArgs e)
        {
            Dictionary<string, string> fields = e.Fields;
            string level = fields["level"];
            string id = fields["id"];

            if (level != "1")
            {
                string nodeTypeAlias = fields["nodeTypeAlias"];
                int nodeId = 0;
                int ancestorId = 0;
                try
                {
                    nodeId = Convert.ToInt32(id);
                    if (nodeId != 0)
                    {
                        IContentService cs = ApplicationContext.Current.Services.ContentService;
                        try
                        {
                            IEnumerable<IContent> ancestors = cs.GetAncestors(nodeId);
                            if (ancestors.Where(x => x.ContentType.Alias.ToLower() == "homepage").Count() == 1)
                            {
                                ancestorId = ancestors.First().Id;
                            }
                            if (ancestorId > 0)
                            {
                                e.Fields.Add("siteNode", ancestorId.ToString());
                            }
                        }
                        catch (Exception)
                        {
                            // Do nothing
                        }
                    }
                }
                catch (Exception)
                {
                    // Do nothing
                }
            }
            else
            {
                e.Fields.Add("siteNode", id);
            }
        }
    }

Is this the right approach or have I misunderstood?

You didn't add your event binding logic, so your events will never fire. You need to move the logic from the ctor in your ExamineEvents to the OnApplicationStarted method of your AppEvents.... specifically this block of code:

 ExamineManager.Instance.IndexProviderCollection["ExternalIndexer"].GatheringNodeData += ExamineEvents_GatheringNodeData;
 ExamineManager.Instance.IndexProviderCollection["AxumIndexer"].GatheringNodeData += ExamineEvents_GatheringNodeData;

By the way, since you are looking up all ancestors for a single node each time a document is indexed, if you rebuild all and have a lot of nodes, this will be very aweful for performance.

Okay, these suggested changes have now completely broken my application. Here is the final code I now have based upon the suggestions above:

public class AppEvents : IApplicationEventHandler
    {
        public void OnApplicationInitialized(UmbracoApplicationBase umbracoApplication, ApplicationContext applicationContext)
        {

        }

        public void OnApplicationStarting(UmbracoApplicationBase umbracoApplication, ApplicationContext applicationContext)
        {
        }

        public void OnApplicationStarted(UmbracoApplicationBase umbracoApplication, ApplicationContext applicationContext)
        {
            var helper = new UmbracoHelper(UmbracoContext.Current);
            ExamineManager.Instance.IndexProviderCollection["AxumIndexer"].GatheringNodeData
                += (sender, e) => AppEvents.GatheringContentData(sender, e, helper);
        }

        public static void GatheringContentData(object sender, IndexingNodeDataEventArgs e, UmbracoHelper helper)
        {
            AddToContentsField(e);
        }

        private static void AddToContentsField(IndexingNodeDataEventArgs e)
        {
            Dictionary<string, string> fields = e.Fields;
            string level = fields["level"];
            string id = fields["id"];

            if (level != "1")
            {
                string nodeTypeAlias = fields["nodeTypeAlias"];
                int nodeId = 0;
                int ancestorId = 0;
                try
                {
                    nodeId = Convert.ToInt32(id);
                    if (nodeId != 0)
                    {
                        IContentService cs = ApplicationContext.Current.Services.ContentService;
                        try
                        {
                            IEnumerable<IContent> ancestors = cs.GetAncestors(nodeId).ToArray();
                            if (ancestors.Where(x => x.ContentType.Alias.ToLower() == "homepage").Count() == 1)
                            {
                                ancestorId = ancestors.First().Id;
                            }
                            if (ancestorId > 0)
                            {
                                if (e.Fields.ContainsKey("siteNode"))
                                {
                                    e.Fields["siteNode"] = ancestorId.ToString();
                                }
                                else
                                {
                                    e.Fields.Add("siteNode", ancestorId.ToString());
                                }
                            }
                        }
                        catch (Exception)
                        {
                            // Do nothing
                        }
                    }
                }
                catch (Exception)
                {
                    // Do nothing
                }
            }
            else
            {
                e.Fields.Add("siteNode", id);
            }
        }
    }
}

For some reason when I save a Node in the back office, it first seems to run the GatheringContentData method. It then jumps up to the OnApplicationStarted and highlights the:

ExamineManager.Instance.IndexProviderCollection["AxumIndexer"].GatheringNodeData
                += (sender, e) => AppEvents.GatheringContentData(sender, e, helper); 

Following this it jumps backwards and forwards between the two loads of times. When I use the back office Examine searcher tool to look for the node I have just saved, it is present in the index complete with the siteNode field I have added to the index using my code. However, when I run the other part of my application that relies on this or even indexing in general, it now fails.

For instance, if I run the following code:

        ISearchCriteria criteria = AxumSearcher.CreateSearchCriteria();
        IBooleanOperation query = criteria.NodeTypeAlias("homepage");

        ISearchResults results = AxumSearcher.Search(query.Compile());

Nothing is returned anymore. When I check the index, it would seem that for some reason now it is no longer writing my homepage to the index.

Could somebody please point me in the right direction as there is barely any literature on these new methods on Our and my application is dependent on the Indexing working in this way.

The reason I am having to do this in the first place is because the culture of a page doesn't seem to be indexed so I am storing a siteNode against every page so that I can tell which is the root element and apply logic accordingly.

I have now re-engineered this to the following based upon this article however I now find that nothing is being saved to my custom index at all.

using System;
using System.Text;
using System.Linq;
using System.Xml.Linq;
using System.Collections.Generic;
using Examine;
using umbraco.BusinessLogic;
using System.Web;
using Umbraco.Core;
using Umbraco.Core.Models;
using Umbraco.Core.Services;
using Umbraco.Web.WebApi;
using Umbraco.Web;
using UmbracoExamine;

namespace Lost_World_Adventures.App_Code.Examine_Extensions
{
    public class AppEvents : IApplicationEventHandler
    {
        public void OnApplicationInitialized(UmbracoApplicationBase umbracoApplication, ApplicationContext applicationContext)
        {
        }

        public void OnApplicationStarting(UmbracoApplicationBase umbracoApplication, ApplicationContext applicationContext)
        {
        }

        public void OnApplicationStarted(UmbracoApplicationBase umbracoApplication, ApplicationContext applicationContext)
        {
            var helper = new UmbracoHelper(UmbracoContext.Current);
            ExamineManager.Instance.IndexProviderCollection["AxumIndexer"].GatheringNodeData
                                += (sender, e) => ExamineEvents.GatheringContentData(sender, e, helper);
        }

        public static void GatheringContentData(object sender, IndexingNodeDataEventArgs e, UmbracoHelper helper)
        {

        }
    }

    public static class ExamineEvents
    {
        public static void GatheringContentData(object sender, IndexingNodeDataEventArgs e, UmbracoHelper helper)
        {
            var content = helper.TypedContent(e.NodeId);
            var homepage = content.Ancestor("homepage");

            e.Fields.Add("siteNode", homepage.Id.ToString());
        }
    }
}

http://staheri.com/my-blog/2015/march/custom-examine-indexing-using-umbraco-cache/

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