Create a computed date field

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In this article

Step 1: Create the required C# project
Step 2: Configure the computed field
Step 3: Rebuild your indexes
Step 4: Validate the computed field has been added

Suppose you want to create some kind of archiving system in Sitecore by adding a computed field. For example, you would like to add an archivedate whose value would be one year after the item creation date (that is, created field in the example below).

This article provides the steps to achieve this.

The Coveo Platform system date field and Coveo for Sitecore date field formats are incompatible. You can’t use a mapping to populate a Coveo Platform system date field with a Coveo for Sitecore computed date field.

Note

If necessary, see Implement and configure a computed field in your index for more details on each step.

Step 1: Create the required C# project

Create a new C# project named Coveo.Custom that references the Sitecore.ContentSearch and Sitecore.Kernel assemblies.

Create a new class named ArchiveDateField in the Coveo.Custom namespace with the following code.

using System;
using Sitecore;
using Sitecore.ContentSearch;
using Sitecore.ContentSearch.ComputedFields;

namespace Coveo.Custom
{
    public class ArchiveDateField : IComputedIndexField
    {
        // The 'Z' at the end of the format string tells Coveo
        // that the date value represents Universal time.
        private const string COVEO_INDEX_DATE_FORMAT = "yyyy/MM/dd@HH:mm:ssZ";
        private const string SITECORE_CREATED_FIELD = "__Created";
        /// <inheritdoc />
        public string FieldName { get; set; }
        /// <inheritdoc />
        public string ReturnType
        {
            get
            {
                return "datetime";
            }
            set
            {
            }
        }
        /// <inheritdoc />
        public object ComputeFieldValue(IIndexable p_Indexable)
        {
            SitecoreIndexableItem indexableItem = p_Indexable as SitecoreIndexableItem;
            if (indexableItem != null)
            {
                IIndexableDataField dateField = indexableItem.GetFieldByName(SITECORE_CREATED_FIELD);
                if (dateField != null)
                {
                    DateTime itemCreationDate = DateUtil.ParseDateTime(dateField.Value.ToString(), DateTime.MaxValue);
                    // Ensure that the date uses universal time
                    if (itemCreationDate.Kind != DateTimeKind.Utc)
                    {
                        itemCreationDate = itemCreationDate.ToUniversalTime();
                    }
                    return itemCreationDate.AddYears(1).ToString(COVEO_INDEX_DATE_FORMAT);
                }
            }
            return null;
        }
    }
}

To create a computed date field, the ReturnType property must return the datetime string and the ComputeFieldValue method must return the date formatted as yyyy/MM/dd@HH:mm:ssZ.

Compile your project.
Copy the resulting assembly (Coveo.Custom.dll) to the bin folder of your Sitecore instance.

Step 2: Configure the computed field

In Coveo.SearchProvider.Custom.config, add the following element as a child of the <fields hint="raw:AddComputedIndexField"> element.
```
<field fieldName="archivedate">Coveo.Custom.ArchiveDateField, Coveo.Custom</field>
```

In Coveo.SearchProvider.Custom.config, add the following element as a child of the <fieldNames hint="raw:AddFieldByFieldName> element.

<fieldType fieldName="archivedate" settingType="Coveo.Framework.Configuration.FieldConfiguration, Coveo.Framework" returnType="System.DateTime" />

Step 3: Rebuild your indexes

Rebuild your search indexes, or at least re-index the Sitecore items which need the new field.

Step 4: Validate the computed field has been added

Validate that your new field has been added on your items using the Content Browser (platform-ca | platform-eu | platform-au). Its value should be one year after the item creation date.

When running computed field code, check your logs for computed field errors indicating items aren’t being indexed. Implement proper exception handling to avoid these issues. For example, you might want to stop the process or set a fallback value for a computed field when suitable.