Querying child collections by id in RavenDB

ChildCollectionQueryTests.cs

public class Foo
{
	public string Id { get; set; }
	public string Name { get; set; }
	public Bar[] Bars { get; set; }
}

public class Bar
{
	public string Id { get; set; }
	public string Name { get; set; }
}

public class FooIndex : AbstractIndexCreationTask<Foo>
{
	public FooIndex()
	{
		Map = docs => from doc in docs
			select new
			{
				doc.Name,
				Bars_Id = doc.Bars.Select(bar => bar.Id)
			};

		Store(x => x.Bars.Select(b => b.Id), FieldStorage.Yes);
		Index(x => x.Bars.Select(b => b.Id), FieldIndexing.Analyzed);
	}
}

public class FooChildIdsNotAnalyzedIndex : AbstractIndexCreationTask<Foo>
{
	public FooChildIdsNotAnalyzedIndex()
	{
		Map = docs => from doc in docs
			select new
			{
				doc.Name,
				BarIds = doc.Bars.Select(bar => bar.Id)
			};

		Store(x => x.Bars.Select(b => b.Id), FieldStorage.Yes);
		Index(x => x.Bars.Select(b => b.Id), FieldIndexing.NotAnalyzed);
	}
}

public class NoStaleQueriesAllowed : IDocumentQueryListener
{
	public void BeforeQueryExecuted(IDocumentQueryCustomization queryCustomization)
	{
		queryCustomization.WaitForNonStaleResults();
	}
}

public class ChildCollectionQueryTests
{
	private readonly EmbeddableDocumentStore documentStore;

	public ChildCollectionQueryTests()
	{
		documentStore = new EmbeddableDocumentStore
		{
			Configuration =
			{
				RunInUnreliableYetFastModeThatIsNotSuitableForProduction = true,
				RunInMemory = true
			}
		};

		documentStore.ConfigureSerializers();

		documentStore.RegisterListener(new NoStaleQueriesAllowed());
		documentStore.Initialize();
	}

	public void searching_by_child_id_on_not_analyzed_errors()
	{
		new FooChildIdsNotAnalyzedIndex().Execute(documentStore.DatabaseCommands, documentStore.Conventions);

		using (var session = documentStore.OpenSession())
		{
			var fooOne = new Foo {Id = "foos/1", Name = "First Foo", Bars = new[] {new Bar {Id = "Bars/1", Name = "Bar"}}};
			var fooTwo = new Foo {Id = "foos/2", Name = "Foo the Greater"};

			session.Store(fooOne);
			session.Store(fooTwo);
			session.SaveChanges();

			var fooSearch = session.Query<Foo, FooChildIdsNotAnalyzedIndex>().Where(x => x.Bars.Any(b => b.Id == "Bars/1"));
			Should.Throw<ArgumentException>(() => fooSearch.ToList());
		}
	}

	public void can_search_child_collection_by_id_if_analyzed()
	{
		new FooIndex().Execute(documentStore.DatabaseCommands, documentStore.Conventions);

		using (var session = documentStore.OpenSession())
		{
			var fooOne = new Foo {Id = "foos/1", Name = "First Foo", Bars = new[] {new Bar {Id = "Bars/1", Name = "Bar"}}};
			var fooTwo = new Foo {Id = "foos/2", Name = "Foo the Greater"};

			session.Store(fooOne);
			session.Store(fooTwo);
			session.SaveChanges();

			var fooSearch = session.Query<Foo, FooIndex>().Where(x => x.Bars.Any(b => b.Id == "Bars/1"));
			var foos = fooSearch.ToList();

			foos.Count.ShouldBe(1);
		}
	}
}

Note the failure here is that, while Raven's recommendation is to store Ids as NotAnalyzed, you must store them Analyzed if you're storing a collection... which makes sense. an id (or any field) in a child collection is just a piece of data as far as Raven cares.

Also, note the mapped field must be called Bars_Id. This is due to the convention-based naming Raven uses