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Converting to JSON and accessing metadata

Entities passed to index can be converted to JSON using AsDocument method, there is also a possibility to access metadata for a specified object using MetadataFor method.

AsDocument - converting to JSON

public class Products_AllProperties : AbstractIndexCreationTask<Product, Products_AllProperties.Result>
{
	public class Result
	{
		public string Query { get; set; }
	}

	public Products_AllProperties()
	{
		Map = products => from product in products
					select new
					{
						// convert product to JSON and select all properties from it
						Query = AsDocument(product).Select(x => x.Value)
					};

		// mark 'Query' field as analyzed which enables full text search operations
		Index(x => x.Query, FieldIndexing.Analyzed);
	}
}

IList<Product> results = session
	.Query<Products_AllProperties.Result, Products_AllProperties>()
	.Where(x => x.Query == "Chocolade")
	.OfType<Product>()
	.ToList();

MetadataFor - accessing metadata

public class Products_WithMetadata : AbstractIndexCreationTask<Product>
{
	public class Result
	{
		public DateTime LastModified { get; set; }
	}

	public Products_WithMetadata()
	{
		Map = products => from product in products
					let metadata = MetadataFor(product)
					select new
					{
						LastModified = metadata.Value<DateTime>("Last-Modified")
					};
	}
}

IList<Product> results = session
	.Query<Products_WithMetadata.Result, Products_WithMetadata>()
	.OrderByDescending(x => x.LastModified)
	.OfType<Product>()
	.ToList();