RavenDB - An Introduction

using System.Linq;
using Raven.Database.Extensions;
using Raven.Database.Indexing;
using Raven.Database.Json;

namespace Raven.Database.Tasks
{
	/// <summary>
	/// 	Indexing a range of documents
	/// 	A range of documents is a stable range, which can be queried even if document addition / removal
	/// 	occured since the time that the range was taken to the time it was queried.
	/// </summary>
	public class IndexDocumentRangeTask : Task
	{
		public int FromId { get; set; }
		public int ToId { get; set; }

		public override string ToString()
		{
			return string.Format("IndexDocumentRangeTask - Index: {0}, FromId: {1}, ToId: {2}",
			                     Index, FromId, ToId);
		}

		public override void Execute(WorkContext context)
		{
			var viewGenerator = context.IndexDefinitionStorage.GetViewGenerator(Index);
			if (viewGenerator == null)
				return; // index was deleted, probably
			context.TransactionaStorage.Batch(actions =>
			{
				var docsToIndex = actions.DocumentsById(new Reference<bool>(), FromId, ToId, 100)
					.Select(d => d.Item1)
					.Where(x => x != null)
					.Select(s => JsonToExpando.Convert(s.ToJson()));
				context.IndexStorage.Index(Index, viewGenerator, docsToIndex, context, actions);
				actions.Commit();
			});
		}
	}
}