Clean up and simplify FieldSelection, re-implement it on GetResponse

Author: gmarz

src/Nest/CommonAbstractions/Fields/FieldSelection.cs

@@ -10,69 +10,63 @@ namespace Nest
 {
 	public interface IFieldSelection<out T>
 	{
-		/// <summary>
-		/// As of elasticsearch fields are always returned as an array. except for internal metadata values such as routing.
-		/// </summary>
-		/// <typeparam name="K">The type to return the value as, remember that if your field is a string K should be string[]</typeparam>
-		K FieldValues<K>(string path);
-		
+		K[] FieldValues<K>(string path);
+
+		K FieldValue<K>(string path);
+
 		K[] FieldValues<TBindTo, K>(Expression<Func<TBindTo, object>> objectPath)
 			where TBindTo : class;
 
+		K FieldValue<TBindTo, K>(Expression<Func<TBindTo, object>> objectPath)
+			where TBindTo : class;
+
 		IDictionary<string, object> FieldValuesDictionary { get; set; }
 	}
 
 	public class FieldSelection<T> : IFieldSelection<T>
 	{
+		private IFieldSelection<T> Self => this;
+
 		private ElasticInferrer Infer { get; set; }
-		public FieldSelection(IConnectionSettingsValues settings, IDictionary<string, object> valuesDictionary = null)
-		{
-			this.Infer = settings.Inferrer;
-			((IFieldSelection<T>)this).FieldValuesDictionary = valuesDictionary;
-		}
 
-		[JsonConverter(typeof(VerbatimDictionaryKeysJsonConverter))]
 		IDictionary<string, object> IFieldSelection<T>.FieldValuesDictionary { get; set; }
 
-		/// <summary>
-		/// As of elasticsearch fields are always returned as an array. except for internal metadata values such as routing.
-		/// </summary>
-		/// <typeparam name="K">The type to return the value as, remember that if your field is a string K should be string[]</typeparam>
-		public K FieldValues<K>(string path)
+		public FieldSelection(ElasticInferrer inferrer, IDictionary<string, object> valuesDictionary = null)
 		{
-			return this.FieldArray<K>(path);
+			this.Infer = inferrer;
+			this.Self.FieldValuesDictionary = valuesDictionary;
 		}
 
-		/// <summary>
-		/// As of elasticsearch fields are always returned as an array. 
-		/// except for internal metadata values such as routing.
-		/// </summary>
+		public K[] FieldValues<K>(string path)
+		{
+			return this.FieldArray<K[]>(path);
+		}
+
+		public K FieldValue<K>(string path) => FieldValues<K>(path).FirstOrDefault();
+
+
 		public K[] FieldValues<TBindTo, K>(Expression<Func<TBindTo, object>> objectPath)
 			where TBindTo : class
 		{
 			var path = this.Infer.Field(objectPath);
 			return this.FieldArray<K[]>(path);
 		}
 
-		/// <summary>
-		/// As of elasticsearch fields are always returned as an array. 
-		/// except for internal metadata values such as routing.
-		/// </summary>
+		public K FieldValue<TBindTo, K>(Expression<Func<TBindTo, object>> objectPath) 
+			where TBindTo : class => FieldValues<TBindTo, K>(objectPath).FirstOrDefault();
+
 		public K[] FieldValues<K>(Expression<Func<T, K>> objectPath)
 		{
 			var path = this.Infer.Field(objectPath);
 			return this.FieldArray<K[]>(path);
 		}
 
-		/// <summary>
-		/// As of elasticsearch fields are always returned as an array. except for internal metadata values such as routing.
-		/// </summary>
-		/// <typeparam name="K">The type to return the value as, remember that if your field is a string K should be string[]</typeparam>
+		public K FieldValue<K>(Expression<Func<T, K>> objectPath) => FieldValues<K>(objectPath).FirstOrDefault();
+
 		private K FieldArray<K>(string path)
 		{
-			var fieldValues = ((IFieldSelection<T>)this).FieldValuesDictionary;
 			object o;
-			if (fieldValues != null && fieldValues.TryGetValue(path, out o))
+			if (this.Self.FieldValuesDictionary != null && this.Self.FieldValuesDictionary.TryGetValue(path, out o))
 			{
 				var t = typeof(K);
 				if (o is JArray && t.GetInterfaces().Contains(typeof(IEnumerable)))

src/Nest/CommonAbstractions/SerializationBehavior/StatefulDeserialization/ConcreteTypeConverter.cs

@@ -80,7 +80,7 @@ public override object ReadJson(JsonReader reader, Type objectType, object exist
 
 			var instance = (Hit<T>)(typeof(Hit<T>).CreateInstance());
 			serializer.Populate(reader, instance);
-			instance.Fields = new FieldSelection<T>(serializer.GetConnectionSettings(), instance._fields);
+			instance.Fields = new FieldSelection<T>(serializer.GetConnectionSettings().Inferrer, instance._fields);
 			return instance;
 		}
 
@@ -160,7 +160,7 @@ internal static Type GetConcreteTypeUsingSelector<T>(
 			dynamic d = jObject;
 			var fields = jObject["fields"];
 			var fieldSelectionData = fields?.ToObject<IDictionary<string, object>>();
-			var sel = new FieldSelection<T>(settings, fieldSelectionData);
+			var sel = new FieldSelection<T>(settings.Inferrer, fieldSelectionData);
 			var hitDynamic = new Hit<dynamic>();
 			//favor manual mapping over doing Populate twice.
 			hitDynamic._fields = fieldSelectionData;

src/Nest/Document/Multiple/MultiGet/Response/MultiGetHit.cs

@@ -21,7 +21,6 @@ public interface IMultiGetHit<out T> where T : class
 	public class MultiGetHit<T> : IMultiGetHit<T>
 		where T : class
 	{
-		//[JsonProperty(PropertyName = "fields")]
 		public IFieldSelection<T> FieldSelection { get; internal set; }
 
 		[JsonProperty(PropertyName = "_source")]

src/Nest/Document/Multiple/MultiGet/Response/MultiGetHitJsonConverter.cs

@@ -41,7 +41,7 @@ private static void CreateMultiHit<T>(MultiHitTuple tuple, JsonSerializer serial
 			serializer.Populate(reader, hit);
 
 			var settings = serializer.GetConnectionSettings();
-			var f = new FieldSelection<T>(settings);
+			var f = new FieldSelection<T>(settings.Inferrer);
 			var source = tuple.Hit["fields"];
 			if (source != null)
 			{

src/Nest/Document/Single/Get/ElasticClient-Get.cs

@@ -1,6 +1,7 @@
 using System;
 using System.Threading.Tasks;
 using Elasticsearch.Net;
+using System.IO;
 
 namespace Nest
 {
@@ -33,9 +34,10 @@ public IGetResponse<T> Get<T>(DocumentPath<T> document, Func<GetDescriptor<T>, I
 			this.Get<T>(selector.InvokeOrDefault(new GetDescriptor<T>(document)));
 
 		/// <inheritdoc/>
-		public IGetResponse<T> Get<T>(IGetRequest request) where T : class => 
+		public IGetResponse<T> Get<T>(IGetRequest request) where T : class =>
 			this.Dispatcher.Dispatch<IGetRequest, GetRequestParameters, GetResponse<T>>(
 				request,
+				(r, s) => DeserializeGetResponse<T>(s),
 				(p, d) => this.LowLevelDispatch.GetDispatch<GetResponse<T>>(p)
 			);
 
@@ -44,10 +46,19 @@ public Task<IGetResponse<T>> GetAsync<T>(DocumentPath<T> document, Func<GetDescr
 			this.GetAsync<T>(selector.InvokeOrDefault(new GetDescriptor<T>(document)));
 
 		/// <inheritdoc/>
-		public Task<IGetResponse<T>> GetAsync<T>(IGetRequest request) where T : class => 
+		public Task<IGetResponse<T>> GetAsync<T>(IGetRequest request) where T : class =>
 			this.Dispatcher.DispatchAsync<IGetRequest, GetRequestParameters, GetResponse<T>, IGetResponse<T>>(
 				request,
+				(r, s) => DeserializeGetResponse<T>(s),
 				(p, d) => this.LowLevelDispatch.GetDispatchAsync<GetResponse<T>>(p)
 			);
+
+		private GetResponse<T> DeserializeGetResponse<T>(Stream stream)
+			where T : class
+		{
+			var response = Serializer.Deserialize<GetResponse<T>>(stream);
+			response.Inferrer = this.ConnectionSettings.Inferrer;
+			return response;
+		}
 	}
 }

src/Nest/Document/Single/Get/GetResponse.cs

@@ -2,6 +2,7 @@
 using System.Collections.Generic;
 using System.Linq.Expressions;
 using Newtonsoft.Json;
+using System.Linq;
 
 namespace Nest
 {
@@ -19,7 +20,7 @@ public interface IGetResponse<T> : IResponse where T : class
 	[JsonObject(MemberSerialization.OptIn)]
 	public class GetResponse<T> : BaseResponse, IGetResponse<T> where T : class
 	{
-		private IDictionary<string, object> _fieldValues;
+		internal ElasticInferrer Inferrer { get; set; }
 
 		[JsonProperty(PropertyName = "_index")]
 		public string Index { get; private set; }
@@ -39,46 +40,20 @@ public class GetResponse<T> : BaseResponse, IGetResponse<T> where T : class
 		[JsonProperty(PropertyName = "_source")]
 		public T Source { get; private set; }
 
-
-		[JsonConverter(typeof(VerbatimDictionaryKeysJsonConverter))]
 		[JsonProperty(PropertyName = "fields")]
-		internal IDictionary<string, object> FieldValues
-		{
-			get { return _fieldValues; }
-			set { _fieldValues = value; }
-		}
+		private IDictionary<string, object> _rawFields;
 
-		//private FieldSelection<T> _fields = null; 
+		private FieldSelection<T> _fields = null; 
 		public FieldSelection<T> Fields
 		{
 			get
 			{
-				//TODO High Priority: Fix field selections
-				throw new NotImplementedException("Fieldselections are broken in 2.0, responses no longer have settings");
-				//if (_fields != null)
-				//	return _fields;
+				if (_fields != null)
+					return _fields;
 
-				//if (this.ApiCall == null)
-				//	return null;
-				//var realSettings = this.ApiCall.Settings as IConnectionSettingsValues;
-
-				//_fields = new FieldSelection<T>(realSettings, FieldValues);
-				//return _fields;
+				_fields = new FieldSelection<T>(Inferrer, _rawFields);
+				return _fields;
 			}
 		}
-
-		public K[] FieldValue<TBindTo, K>(Expression<Func<TBindTo, object>> objectPath)
-			where TBindTo : class
-		{
-			if (this.Fields == null) return default(K[]);
-			return this.Fields.FieldValues<TBindTo,K>(objectPath);
-		}
-
-		public K FieldValue<K>(string path)
-		{
-			if (this.Fields == null) return default(K);
-			return this.Fields.FieldValues<K>(path);
-		}
-
 	}
 }

src/Nest/Document/Single/Index/ElasticClient-Index.cs

@@ -38,7 +38,8 @@ public IIndexResponse Index<T>(T @object, Func<IndexDescriptor<T>, IIndexRequest
 		/// <inheritdoc/>
 		public IIndexResponse Index(IIndexRequest request) =>
 			this.Dispatcher.Dispatch<IIndexRequest, IndexRequestParameters, IndexResponse>(
-				request, this.LowLevelDispatch.IndexDispatch<IndexResponse>
+				request,
+				this.LowLevelDispatch.IndexDispatch<IndexResponse>
 			);
 
 		/// <inheritdoc/>

src/Tests/Document/Single/Get/GetApiTests.cs

@@ -6,18 +6,19 @@
 using Tests.Framework.Integration;
 using Tests.Framework.MockData;
 using Xunit;
+using FluentAssertions;
 
 namespace Tests.Document.Single.Get
 {
 	[Collection(IntegrationContext.ReadOnly)]
 	public class GetApiTests : ApiIntegrationTestBase<IGetResponse<Project>, IGetRequest, GetDescriptor<Project>, GetRequest<Project>>
 	{
-		private string ProjectId => Project.Projects.First().Name;
+		protected string ProjectId => Project.Projects.First().Name;
 
 		public GetApiTests(ReadOnlyCluster cluster, EndpointUsage usage) : base(cluster, usage) { }
 		protected override LazyResponses ClientUsage() => Calls(
-			fluent: (client, f) => client.Get<Project>(this.ProjectId),
-			fluentAsync: (client, f) => client.GetAsync<Project>(this.ProjectId),
+			fluent: (client, f) => client.Get<Project>(this.ProjectId, f),
+			fluentAsync: (client, f) => client.GetAsync<Project>(this.ProjectId, f),
 			request: (client, r) => client.Get<Project>(r),
 			requestAsync: (client, r) => client.GetAsync<Project>(r)
 		);
@@ -30,6 +31,37 @@ protected override LazyResponses ClientUsage() => Calls(
 		protected override bool SupportsDeserialization => false;
 
 		protected override Func<GetDescriptor<Project>, IGetRequest> Fluent => null;
+
 		protected override GetRequest<Project> Initializer => new GetRequest<Project>(this.ProjectId);
+
+		protected override void ExpectResponse(IGetResponse<Project> response)
+		{
+			response.Source.Should().NotBeNull();
+			response.Source.Name.Should().Be(ProjectId);
+		}
+	}
+
+	[Collection(IntegrationContext.ReadOnly)]
+	public class GetApiFieldsTests : GetApiTests
+	{
+		public GetApiFieldsTests(ReadOnlyCluster cluster, EndpointUsage usage) : base(cluster, usage) { }
+
+		protected override Func<GetDescriptor<Project>, IGetRequest> Fluent => g => g
+			.Fields(
+				p => p.Name, 
+				p => p.NumberOfCommits
+			);
+
+		protected override GetRequest<Project> Initializer => new GetRequest<Project>(ProjectId)
+		{
+			Fields = Infer.Fields<Project>(p => p.Name, p => p.NumberOfCommits)
+		};
+
+		protected override void ExpectResponse(IGetResponse<Project> response)
+		{
+			response.Fields.Should().NotBeNull();
+			response.Fields.FieldValue(p => p.Name).Should().Be(ProjectId);
+			response.Fields.FieldValue(p => p.NumberOfCommits).Should().BeGreaterThan(0);
+		}
 	}
 }