Umbraco dictionary metadata provider

//WebBootManager.cs:

public override IBootManager Initialize()
{
    //...
    // set metadata provider
    ModelMetadataProviders.Current = new DictionaryMetadataProvider();
    //...
}

//DictionaryMetadataProvider.cs:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Web.Mvc;
using umbraco;
using System.ComponentModel.DataAnnotations;

namespace Umbraco.Web.Mvc
{
    /// <summary>
    /// Model meta data provider that looks up display values and error messages from the Umbraco dictionary
    /// </summary>
    public class DictionaryMetadataProvider : DataAnnotationsModelMetadataProvider
    {
        protected override ModelMetadata CreateMetadata(IEnumerable<Attribute> attributes, Type containerType, Func<object> modelAccessor, Type modelType, string propertyName)
        {
            var metadata = base.CreateMetadata(attributes, containerType, modelAccessor, modelType, propertyName);

            if (containerType != null && propertyName != null)
            {
                string dictKey = containerType.Name + "." + propertyName;
                metadata.DisplayName = LookupDictionaryValue(dictKey, metadata.DisplayName);
                metadata.NullDisplayText = LookupDictionaryValue(dictKey + ".NullDisplayText", metadata.NullDisplayText);

                foreach (var attribute in attributes)
                {
                    if (attribute is ValidationAttribute)
                    {
                        string attributeName = attribute.GetType().Name;

                        if (attributeName.EndsWith("Attribute"))
                            attributeName = attributeName.Substring(0, attributeName.Length - 9);

                        string attributeDictKey = containerType.Name + "." + propertyName + "." + attributeName;

                        var validationAttribute = (ValidationAttribute)attribute;

                        if (validationAttribute.ErrorMessageResourceName == null)
                        {
                            string errorMessage = LookupDictionaryValue(attributeDictKey, null);

                            if (errorMessage != null)
                                validationAttribute.ErrorMessage = errorMessage;
                        }
                    }
                }
            }

            return metadata;
        }

        /// <summary>
        /// Look up a value from the Umbraco dictionary
        /// </summary>
        /// <param name="dictKey">The dictionary item key</param>
        /// <param name="defaultValue">The default value to return if the dictionary item was not found</param>
        /// <returns>The dictionary item value, or defaultValue if item was not found in the dictionary</returns>
        protected virtual string LookupDictionaryValue(string dictKey, string defaultValue)
        {
            string dictValue = library.GetDictionaryItem(dictKey);
            return !string.IsNullOrEmpty(dictValue) ? dictValue : defaultValue;
        }
    }
}