Custom indexing

Learn how to build and customize the indexes that comes with your Umbraco website.

Customizing the built in indexes

You can modify the built-in indexes in the following ways:

• Events - giving you control over exactly what data goes into them and how the fields are configured

• Changing the field value types to change how values are stored in the index

• Changing the IValueSetValidator to change what goes into the index

• Take control of the entire index creation pipeline to change the implementation

We can do all this by using the ConfigureNamedOptions pattern.

Creating a ConfigureOptions class

We will start by creating a ConfigureExamineOptions class, that derives from IConfigureNamedOptions<LuceneDirectoryIndexOptions>:

using Examine.Lucene;
using Microsoft.Extensions.Options;

namespace Umbraco.Docs.Samples.Web.CustomIndexing;

public class ConfigureExternalIndexOptions : IConfigureNamedOptions<LuceneDirectoryIndexOptions>
{
    public void Configure(string name, LuceneDirectoryIndexOptions options)
    {
        throw new System.NotImplementedException();
    }

    public void Configure(LuceneDirectoryIndexOptions options)
    {
        throw new System.NotImplementedException();
    }
}

In this sample we are altering the external index and thus we name the class ConfigureExternalIndexOptions. If you are altering multiple indexes, it is recommended to have separate classes for each index - i.e. ConfigureExternalIndexOptions for the external index, ConfigureInternalIndexOptions for the internal index and so on.

When using the ConfigureNamedOptions pattern, we have to register this in a composer for it to configure our indexes, this can be done like this:

using Microsoft.Extensions.DependencyInjection;
using Umbraco.Cms.Core.Composing;
using Umbraco.Cms.Core.DependencyInjection;

namespace Umbraco.Docs.Samples.Web.CustomIndexing;

public class ExamineComposer : IComposer
{
    public void Compose(IUmbracoBuilder builder)
    {
        builder.Services.ConfigureOptions<ConfigureExternalIndexOptions>();
    }
}

Changing field value types

By default, Examine will store values into the Lucene index as "Full Text" fields, meaning the values will be indexed and analyzed for a textual search. However, if a field value is numerical, date/time, or another non-textual value type, you might want to change how the value is stored in the index. This will let you take advantage of some value type-specific search features such as numerical or date range.

There is some documentation about this in the Examine documentation.

The easiest way to modify how a field is configured is using the ConfigureNamedOptions pattern like so:

using Examine;
using Examine.Lucene;
using Microsoft.Extensions.Options;
using Umbraco.Cms.Core;

namespace Umbraco.Docs.Samples.Web.CustomIndexing;

public class ConfigureExternalIndexOptions : IConfigureNamedOptions<LuceneDirectoryIndexOptions>
{
    public void Configure(string name, LuceneDirectoryIndexOptions options)
    {
        if (name.Equals(Constants.UmbracoIndexes.ExternalIndexName))
        {
            options.FieldDefinitions.AddOrUpdate(new FieldDefinition("price", FieldDefinitionTypes.Double));
        }
    }

    // Part of the interface, but does not need to be implemented for this.
    public void Configure(LuceneDirectoryIndexOptions options)
    {
        throw new System.NotImplementedException();
    }
}

This will ensure that the price field in the index is treated as a double type (if the price field does not exist in the index, it is added).

Changing IValueSetValidator

An IValueSetValidator is responsible for validating a ValueSet to see if it should be included in the index. For example, by default the validation process for the ExternalIndex checks if a ValueSet has a category type of either "media" or "content" (not member). If a ValueSet was passed to the ExternalIndex and it did not pass this requirement it would be ignored.

The IValueSetValidator is also responsible for filtering the data in the ValueSet. For example, by default the validator for the MemberIndex will validate on all the default member properties, so an extra property "PhoneNumber", would not pass validation, and therefore not be included.

The IValueSetValidator implementation for the built-in indexes, can be changed like this:

using Examine.Lucene;
using Microsoft.Extensions.Options;
using Umbraco.Cms.Core;
using Umbraco.Cms.Infrastructure.Examine;

namespace Umbraco.Docs.Samples.Web.CustomIndexing;

public class ConfigureMemberIndexOptions : IConfigureNamedOptions<LuceneDirectoryIndexOptions>
{
    public void Configure(string name, LuceneDirectoryIndexOptions options)
    {
        if (name.Equals(Constants.UmbracoIndexes.MembersIndexName))
        {
            options.Validator = new MemberValueSetValidator(null, null, new[] {"email"}, null);
        }
    }

    // Part of the interface, but does not need to be implemented for this.
    public void Configure(LuceneDirectoryIndexOptions options)
    {
        throw new System.NotImplementedException();
    }
}

Remember to register ConfigureMemberIndexOptions in your composer.

Creating your own index

The following example will show how to create an index that will only include nodes based on the document type product.

We always recommend that you use the existing built in ExternalIndex. You should then query based on the NodeTypeAlias instead of creating a new separate index based on that particular node type. However, should the need arise, the example below will show you how to do it.

Take a look at our Examine Quick Start to see some examples of how to search the ExternalIndex.

To create this index we need five things:

1. An UmbracoExamineIndex implementation that defines the index.

2. An IConfigureNamedOptions implementation that configures the index fields and options.

3. An IValueSetBuilder implementation that builds index value sets a piece of content.

4. An IndexPopulator implementation that populates the index with the value sets for all applicable content.

5. An INotificationHandler implementation that updates the index when content changes.

6. A composer that adds all these services to the runtime.

ProductIndex

using Examine.Lucene;
using Microsoft.Extensions.Options;
using Umbraco.Cms.Core.Services;
using Umbraco.Cms.Infrastructure.Examine;
using IHostingEnvironment = Umbraco.Cms.Core.Hosting.IHostingEnvironment;

namespace Umbraco.Docs.Samples.Web.CustomIndexing;

public class ProductIndex : UmbracoExamineIndex
{
    public ProductIndex(
        ILoggerFactory loggerFactory,
        string name,
        IOptionsMonitor<LuceneDirectoryIndexOptions> indexOptions,
        IHostingEnvironment hostingEnvironment,
        IRuntimeState runtimeState)
        : base(loggerFactory,
        name,
        indexOptions,
        hostingEnvironment,
        runtimeState)
    {
    }
}

ConfigureProductIndexOptions

using Examine;
using Examine.Lucene;
using Lucene.Net.Analysis.Standard;
using Lucene.Net.Index;
using Lucene.Net.Util;
using Microsoft.Extensions.Options;
using Umbraco.Cms.Core.Configuration.Models;

namespace Umbraco.Docs.Samples.Web.CustomIndexing;

public class ConfigureProductIndexOptions : IConfigureNamedOptions<LuceneDirectoryIndexOptions>
{
    private readonly IOptions<IndexCreatorSettings> _settings;

    public ConfigureProductIndexOptions(IOptions<IndexCreatorSettings> settings)
        => _settings = settings;

    public void Configure(string? name, LuceneDirectoryIndexOptions options)
    {
        if (name?.Equals("ProductIndex") is false)
        {
            return;
        }

        options.Analyzer = new StandardAnalyzer(LuceneVersion.LUCENE_48);

        options.FieldDefinitions = new(
            new("id", FieldDefinitionTypes.Integer),
            new("name", FieldDefinitionTypes.FullText)
        );

        options.UnlockIndex = true;

        if (_settings.Value.LuceneDirectoryFactory == LuceneDirectoryFactory.SyncedTempFileSystemDirectoryFactory)
        {
            // if this directory factory is enabled then a snapshot deletion policy is required
            options.IndexDeletionPolicy = new SnapshotDeletionPolicy(new KeepOnlyLastCommitDeletionPolicy());
        }
    }

    // not used
    public void Configure(LuceneDirectoryIndexOptions options) => throw new NotImplementedException();
}

ProductIndexValueSetBuilder

using Examine;
using Umbraco.Cms.Core.Models;
using Umbraco.Cms.Infrastructure.Examine

namespace Umbraco.Docs.Samples.Web.CustomIndexing;

public class ProductIndexValueSetBuilder : IValueSetBuilder<IContent>
{
    public IEnumerable<ValueSet> GetValueSets(params IContent[] contents)
    {
        foreach (IContent content in contents.Where(CanAddToIndex))
        {
            var indexValues = new Dictionary<string, object>
            {
                // this is a special field used to display the content name in the Examine dashboard
                [UmbracoExamineFieldNames.NodeNameFieldName] = content.Name!,
                ["name"] = content.Name!,
                // add the fields you want in the index
                ["nodeName"] = content.Name!,
                ["id"] = content.Id,
            };

            yield return new ValueSet(content.Id.ToString(), IndexTypes.Content, content.ContentType.Alias, indexValues);
        }
    }

    // filter out all content types except "product"
    private bool CanAddToIndex(IContent content) => content.ContentType.Alias == "product";
}

ProductIndexPopulator

using Examine;
using Umbraco.Cms.Core.Models;
using Umbraco.Cms.Core.Services;
using Umbraco.Cms.Infrastructure.Examine;

namespace Umbraco.Docs.Samples.Web.CustomIndexing;

public class ProductIndexPopulator : IndexPopulator
{
    private readonly IContentService _contentService;
    private readonly ProductIndexValueSetBuilder _productIndexValueSetBuilder;

    public ProductIndexPopulator(IContentService contentService, ProductIndexValueSetBuilder productIndexValueSetBuilder)
    {
        _contentService = contentService;
        _productIndexValueSetBuilder = productIndexValueSetBuilder;
        RegisterIndex("ProductIndex");
    }

    protected override void PopulateIndexes(IReadOnlyList<IIndex> indexes)
    {
        foreach (IIndex index in indexes)
        {
            IContent[] roots = _contentService.GetRootContent().ToArray();
            index.IndexItems(_productIndexValueSetBuilder.GetValueSets(roots));

            foreach (IContent root in roots)
            {
                const int pageSize = 10000;
                var pageIndex = 0;
                IContent[] descendants;
                do
                {
                    descendants = _contentService.GetPagedDescendants(root.Id, pageIndex, pageSize, out _).ToArray();
                    IEnumerable<ValueSet> valueSets = _productIndexValueSetBuilder.GetValueSets(descendants);
                    index.IndexItems(valueSets);

                    pageIndex++;
                }
                while (descendants.Length == pageSize);
            }
        }
    }
}

This is only an example of how you could do indexing. In this example, we're indexing all content, both published and unpublished.

In certain scenarios only published content should be added to the index. To achieve that, you will need to implement your own logic to filter out unpublished content. This can be somewhat tricky as the published state can vary throughout an entire structure of content nodes in the content tree. For inspiration on how to go about such filtering, you can look at the ContentIndexPopulator in Umbraco.

ProductIndexingNotificationHandler

The index will only update its content when you manually trigger an index rebuild in the Examine dashboard. This is not always the desired behavior for a custom index.

To update your index when content changes, you can use notification handlers.

The following handler class does not automatically update the descendant items of the modified content nodes, such as removing descendants of deleted content. If changes to the parent content item can affect its children or descendant items in your setup, please refer to the UmbracoContentIndex.PerformDeleteFromIndex() in Umbraco. Such logic should be applied when both removing and reindexing content items of type product.

using Examine;
using Umbraco.Cms.Core;
using Umbraco.Cms.Core.Cache;
using Umbraco.Cms.Core.Events;
using Umbraco.Cms.Core.Models;
using Umbraco.Cms.Core.Notifications;
using Umbraco.Cms.Core.Services;
using Umbraco.Cms.Core.Services.Changes;
using Umbraco.Cms.Core.Sync;
using Umbraco.Cms.Infrastructure;
using Umbraco.Cms.Infrastructure.Search;

namespace Umbraco.Docs.Samples.Web.CustomIndexing;

public class ProductIndexingNotificationHandler : INotificationHandler<ContentCacheRefresherNotification>
{
    private readonly IRuntimeState _runtimeState;
    private readonly IUmbracoIndexingHandler _umbracoIndexingHandler;
    private readonly IExamineManager _examineManager;
    private readonly IContentService _contentService;
    private readonly ProductIndexValueSetBuilder _productIndexValueSetBuilder;

    public ProductIndexingNotificationHandler(
        IRuntimeState runtimeState,
        IUmbracoIndexingHandler umbracoIndexingHandler,
        IExamineManager examineManager,
        IContentService contentService,
        ProductIndexValueSetBuilder productIndexValueSetBuilder)
    {
        _runtimeState = runtimeState;
        _umbracoIndexingHandler = umbracoIndexingHandler;
        _examineManager = examineManager;
        _contentService = contentService;
        _productIndexValueSetBuilder = productIndexValueSetBuilder;
    }

    /// <summary>
    ///     Updates the index based on content changes.
    /// </summary>
    public void Handle(ContentCacheRefresherNotification notification)
    {
        if (NotificationHandlingIsDisabled())
        {
            return;
        }

        if (!_examineManager.TryGetIndex("ProductIndex", out IIndex? index))
        {
            throw new InvalidOperationException("Could not obtain the product index");
        }

        ContentCacheRefresher.JsonPayload[] payloads = GetNotificationPayloads(notification);

        foreach (ContentCacheRefresher.JsonPayload payload in payloads)
        {
            // Remove
            if (payload.ChangeTypes.HasType(TreeChangeTypes.Remove))
            {
                index.DeleteFromIndex(payload.Id.ToString());
            }
            // Reindex
            else if (payload.ChangeTypes.HasType(TreeChangeTypes.RefreshNode) ||
                     payload.ChangeTypes.HasType(TreeChangeTypes.RefreshBranch))
            {
                IContent? content = _contentService.GetById(payload.Id);
                if (content == null || content.Trashed)
                {
                    index.DeleteFromIndex(payload.Id.ToString());
                    continue;
                }

                IEnumerable<ValueSet> valueSets = _productIndexValueSetBuilder.GetValueSets(content);
                index.IndexItems(valueSets);
            }
        }
    }

    private bool NotificationHandlingIsDisabled()
    {
        // Only handle events when the site is running.
        if (_runtimeState.Level != RuntimeLevel.Run)
        {
            return true;
        }

        if (_umbracoIndexingHandler.Enabled == false)
        {
            return true;
        }

        if (Suspendable.ExamineEvents.CanIndex == false)
        {
            return true;
        }

        return false;
    }

    private ContentCacheRefresher.JsonPayload[] GetNotificationPayloads(CacheRefresherNotification notification)
    {
        if (notification.MessageType != MessageType.RefreshByPayload ||
            notification.MessageObject is not ContentCacheRefresher.JsonPayload[] payloads)
        {
            throw new NotSupportedException();
        }

        return payloads;
    }
}

You can find further inspiration for implementing notification handlers (for example, for media updates) in the UmbracoExamine.PDF package.

ExamineComposer

using Examine;
using Umbraco.Cms.Core.Composing;
using Umbraco.Cms.Core.Notifications;
using Umbraco.Cms.Infrastructure.Examine;

namespace Umbraco.Docs.Samples.Web.CustomIndexing;

public class ExamineComposer : IComposer
{
    public void Compose(IUmbracoBuilder builder)
    {
        builder.Services.AddExamineLuceneIndex<ProductIndex, ConfigurationEnabledDirectoryFactory>("ProductIndex");

        builder.Services.ConfigureOptions<ConfigureProductIndexOptions>();

        builder.Services.AddSingleton<ProductIndexValueSetBuilder>();

        builder.Services.AddSingleton<IIndexPopulator, ProductIndexPopulator>();

        builder.AddNotificationHandler<ContentCacheRefresherNotification, ProductIndexingNotificationHandler>();
    }
}

The order of these registrations matters. It is important to register your index with AddExamineLuceneIndex before calling ConfigureOptions.

Result

Custom product index

Product document