[Backport 7.x] Add Transform settings

src/Nest/XPack/Transform/PreviewTransform/PreviewTransformRequest.cs

@@ -29,6 +29,10 @@ public partial interface IPreviewTransformRequest
 		/// <inheritdoc cref="ITransformSyncContainer"/>
 		[DataMember(Name = "sync")]
 		public ITransformSyncContainer Sync { get; set; }
+
+		/// <inheritdoc cref="IPutTransformRequest.Settings"/>
+		[DataMember(Name = "settings")]
+		public ITransformSettings Settings { get; set; }
 	}
 
 	public partial class PreviewTransformRequest
@@ -50,6 +54,10 @@ public partial class PreviewTransformRequest
 
 		/// <inheritdoc cref="IPreviewTransformRequest.Sync"/>
 		public ITransformSyncContainer Sync { get; set; }
+
+		/// <inheritdoc cref="IPutTransformRequest.Settings"/>
+		[DataMember(Name = "settings")]
+		public ITransformSettings Settings { get; set; }
 	}
 
 	public partial class PreviewTransformDescriptor<TDocument> : IPreviewTransformRequest where TDocument : class
@@ -60,6 +68,7 @@ public partial class PreviewTransformDescriptor<TDocument> : IPreviewTransformRe
 		Time IPreviewTransformRequest.Frequency { get; set; }
 		ITransformPivot IPreviewTransformRequest.Pivot { get; set; }
 		ITransformSyncContainer IPreviewTransformRequest.Sync { get; set; }
+		ITransformSettings IPreviewTransformRequest.Settings { get; set; }
 
 		/// <inheritdoc cref="IPreviewTransformRequest.Description"/>
 		public PreviewTransformDescriptor<TDocument> Description(string description) =>
@@ -83,5 +92,9 @@ public PreviewTransformDescriptor<TDocument> Pivot(Func<TransformPivotDescriptor
 		/// <inheritdoc cref="IPreviewTransformRequest.Sync"/>
 		public PreviewTransformDescriptor<TDocument> Sync(Func<TransformSyncContainerDescriptor<TDocument>, ITransformSyncContainer> selector) =>
 			Assign(selector.InvokeOrDefault(new TransformSyncContainerDescriptor<TDocument>()), (a, v) => a.Sync = v);
+
+		/// <inheritdoc cref="IPreviewTransformRequest.Settings"/>
+		public PreviewTransformDescriptor<TDocument> Settings(Func<TransformSettingsDescriptor, ITransformSettings> selector) =>
+			Assign(selector?.Invoke(new TransformSettingsDescriptor()), (a, v) => a.Settings = v);
 	}
 }

src/Nest/XPack/Transform/PutTransform/PutTransformRequest.cs

@@ -29,6 +29,10 @@ public partial interface IPutTransformRequest
 		/// <inheritdoc cref="ITransformSyncContainer"/>
 		[DataMember(Name = "sync")]
 		public ITransformSyncContainer Sync { get; set; }
+
+		/// <inheritdoc cref="ITransformSettings"/>
+		[DataMember(Name = "settings")]
+		public ITransformSettings Settings { get; set; }
 	}
 
 	/// <inheritdoc cref="IPutTransformRequest"/>
@@ -51,6 +55,9 @@ public partial class PutTransformRequest
 
 		/// <inheritdoc cref="IPutTransformRequest.Sync"/>
 		public ITransformSyncContainer Sync { get; set; }
+
+		/// <inheritdoc cref="IPutTransformRequest.Settings"/>
+		public ITransformSettings Settings { get; set; }
 	}
 
 	public partial class PutTransformDescriptor<TDocument> : IPutTransformRequest where TDocument : class
@@ -61,6 +68,7 @@ public partial class PutTransformDescriptor<TDocument> : IPutTransformRequest wh
 		Time IPutTransformRequest.Frequency { get; set; }
 		ITransformPivot IPutTransformRequest.Pivot { get; set; }
 		ITransformSyncContainer IPutTransformRequest.Sync { get; set; }
+		ITransformSettings IPutTransformRequest.Settings { get; set; }
 
 		/// <inheritdoc cref="IPutTransformRequest.Description"/>
 		public PutTransformDescriptor<TDocument> Description(string description) =>
@@ -84,5 +92,9 @@ public PutTransformDescriptor<TDocument> Pivot(Func<TransformPivotDescriptor<TDo
 		/// <inheritdoc cref="IPutTransformRequest.Sync"/>
 		public PutTransformDescriptor<TDocument> Sync(Func<TransformSyncContainerDescriptor<TDocument>, ITransformSyncContainer> selector) =>
 			Assign(selector?.Invoke(new TransformSyncContainerDescriptor<TDocument>()), (a, v) => a.Sync = v);
+
+		/// <inheritdoc cref="IPutTransformRequest.Settings"/>
+		public PutTransformDescriptor<TDocument> Settings(Func<TransformSettingsDescriptor, ITransformSettings> selector) =>
+			Assign(selector?.Invoke(new TransformSettingsDescriptor()), (a, v) => a.Settings = v);
 	}
 }

src/Nest/XPack/Transform/Transform.cs

@@ -42,5 +42,9 @@ public class Transform
 		/// <inheritdoc cref="ITransformSyncContainer"/>
 		[DataMember(Name = "sync")]
 		public ITransformSyncContainer Sync { get; set; }
+
+		/// <inheritdoc cref="ITransformSettings"/>
+		[DataMember(Name = "settings")]
+		public ITransformSettings Settings { get; set; }
 	}
 }

src/Nest/XPack/Transform/TransformSettings.cs

@@ -0,0 +1,49 @@
+// Licensed to Elasticsearch B.V under one or more agreements.
+// Elasticsearch B.V licenses this file to you under the Apache 2.0 License.
+// See the LICENSE file in the project root for more information
+
+using System.Runtime.Serialization;
+using Elasticsearch.Net.Utf8Json;
+
+namespace Nest
+{
+	/// <summary>
+	/// Transform settings
+	/// <para />
+	/// Valid in Elasticsearch 7.8.0+
+	/// </summary>
+	[InterfaceDataContract]
+	[ReadAs(typeof(TransformSettings))]
+	public interface ITransformSettings
+	{
+		[DataMember(Name = "docs_per_second")]
+		public float? DocsPerSecond { get; set; }
+
+		[DataMember(Name = "max_page_search_size")]
+		public int? MaxPageSearchSize { get; set; }
+	}
+
+	/// <inheritdoc />
+	public class TransformSettings : ITransformSettings
+	{
+		/// <inheritdoc />
+		public float? DocsPerSecond { get; set; }
+
+		/// <inheritdoc />
+		public int? MaxPageSearchSize { get; set; }
+	}
+
+	public class TransformSettingsDescriptor : DescriptorBase<TransformSettingsDescriptor, ITransformSettings>, ITransformSettings
+	{
+		float? ITransformSettings.DocsPerSecond { get; set; }
+		int? ITransformSettings.MaxPageSearchSize { get; set; }
+
+		/// <inheritdoc cref="ITransformSettings.DocsPerSecond"/>
+		public TransformSettingsDescriptor DocsPerSecond(float? docsPerSecond) =>
+			Assign(docsPerSecond, (a, v) => a.DocsPerSecond = v);
+
+		/// <inheritdoc cref="ITransformSettings.MaxPageSearchSize"/>
+		public TransformSettingsDescriptor MaxPageSearchSize(int? maxPageSearchSize) =>
+			Assign(maxPageSearchSize, (a, v) => a.MaxPageSearchSize = v);
+	}
+}

src/Nest/XPack/Transform/UpdateTransform/UpdateTransformRequest.cs

@@ -25,24 +25,31 @@ public partial interface IUpdateTransformRequest
 		/// <inheritdoc cref="ITransformSyncContainer"/>
 		[DataMember(Name = "sync")]
 		public ITransformSyncContainer Sync { get; set; }
+
+		/// <inheritdoc cref="ITransformSettings"/>
+		[DataMember(Name = "settings")]
+		public ITransformSettings Settings { get; set; }
 	}
 
 	public partial class UpdateTransformRequest
 	{
-		/// <inheritdoc cref="IPutTransformRequest.Description"/>
+		/// <inheritdoc cref="IUpdateTransformRequest.Description"/>
 		public string Description { get; set; }
 
-		/// <inheritdoc cref="IPutTransformRequest.Source"/>
+		/// <inheritdoc cref="IUpdateTransformRequest.Source"/>
 		public ITransformSource Source { get; set; }
 
-		/// <inheritdoc cref="IPutTransformRequest.Destination"/>
+		/// <inheritdoc cref="IUpdateTransformRequest.Destination"/>
 		public ITransformDestination Destination { get; set; }
 
-		/// <inheritdoc cref="IPutTransformRequest.Frequency"/>
+		/// <inheritdoc cref="IUpdateTransformRequest.Frequency"/>
 		public Time Frequency { get; set; }
 
-		/// <inheritdoc cref="IPutTransformRequest.Sync"/>
+		/// <inheritdoc cref="IUpdateTransformRequest.Sync"/>
 		public ITransformSyncContainer Sync { get; set; }
+
+		/// <inheritdoc cref="IUpdateTransformRequest.Settings"/>
+		public ITransformSettings Settings { get; set; }
 	}
 
 	public partial class UpdateTransformDescriptor<TDocument> : IUpdateTransformRequest where TDocument : class
@@ -52,6 +59,7 @@ public partial class UpdateTransformDescriptor<TDocument> : IUpdateTransformRequ
 		ITransformDestination IUpdateTransformRequest.Destination { get; set; }
 		Time IUpdateTransformRequest.Frequency { get; set; }
 		ITransformSyncContainer IUpdateTransformRequest.Sync { get; set; }
+		ITransformSettings IUpdateTransformRequest.Settings { get; set; }
 
 		/// <inheritdoc cref="IUpdateTransformRequest.Description"/>
 		public UpdateTransformDescriptor<TDocument> Description(string description) =>
@@ -71,5 +79,9 @@ public UpdateTransformDescriptor<TDocument> Destination(Func<TransformDestinatio
 		/// <inheritdoc cref="IUpdateTransformRequest.Sync"/>
 		public UpdateTransformDescriptor<TDocument> Sync(Func<TransformSyncContainerDescriptor<TDocument>, ITransformSyncContainer> selector) =>
 			Assign(selector?.Invoke(new TransformSyncContainerDescriptor<TDocument>()), (a, v) => a.Sync = v);
+
+		/// <inheritdoc cref="IUpdateTransformRequest.Settings"/>
+		public UpdateTransformDescriptor<TDocument> Settings(Func<TransformSettingsDescriptor, ITransformSettings> selector) =>
+			Assign(selector?.Invoke(new TransformSettingsDescriptor()), (a, v) => a.Settings = v);
 	}
 }

tests/Tests/XPack/Transform/TransformApiWithSettingsTests.cs

@@ -0,0 +1,169 @@
+// Licensed to Elasticsearch B.V under one or more agreements.
+// Elasticsearch B.V licenses this file to you under the Apache 2.0 License.
+// See the LICENSE file in the project root for more information
+
+using System;
+using System.Collections.Generic;
+using Elastic.Elasticsearch.Xunit.XunitPlumbing;
+using Elasticsearch.Net;
+using Nest;
+using Tests.Core.ManagedElasticsearch.Clusters;
+using Tests.Domain;
+using Tests.Framework.EndpointTests;
+using Tests.Framework.EndpointTests.TestState;
+using static Nest.Infer;
+
+namespace Tests.XPack.Transform
+{
+	[SkipVersion("<7.8.0", "Settings introduced in 7.8.0")]
+	public class TransformApiWithSettingsTests : ApiIntegrationTestBase<WritableCluster, PreviewTransformResponse<ProjectTransform>, IPreviewTransformRequest, PreviewTransformDescriptor<Project>, PreviewTransformRequest>
+	{
+		public TransformApiWithSettingsTests(WritableCluster cluster, EndpointUsage usage) : base(cluster, usage) { }
+
+		protected override LazyResponses ClientUsage() => Calls(
+			(client, f) => client.Transform.Preview<Project, ProjectTransform>(f),
+			(client, f) => client.Transform.PreviewAsync<Project, ProjectTransform>(f),
+			(client, r) => client.Transform.Preview<ProjectTransform>(r),
+			(client, r) => client.Transform.PreviewAsync<ProjectTransform>(r)
+		);
+
+		protected override HttpMethod HttpMethod => HttpMethod.POST;
+		protected override string UrlPath => $"_transform/_preview";
+		protected override bool ExpectIsValid => true;
+		protected override int ExpectStatusCode => 200;
+		protected override bool SupportsDeserialization => false;
+		protected override object ExpectJson => new
+		{
+			description = CallIsolatedValue,
+			frequency = "1s",
+			source = new { index = new[] { "project" }, query = new { match_all = new { } } },
+			dest = new { index = $"transform-{CallIsolatedValue}" },
+			pivot = new
+			{
+				aggregations = new
+				{
+					averageCommits = new
+					{
+						avg = new
+						{
+							field = "numberOfCommits"
+						}
+					},
+					sumIntoMaster = new
+					{
+						scripted_metric = new
+						{
+							combine_script = new
+							{
+								source = "long sum = 0; for (s in state.masterCommits) { sum += s } return sum"
+							},
+							init_script = new
+							{
+								source = "state.masterCommits = []"
+							},
+							map_script = new
+							{
+								source = "state.masterCommits.add(doc['branches.keyword'].contains('master')? 1 : 0)"
+							},
+							reduce_script = new
+							{
+								source = "long sum = 0; for (s in states) { sum += s } return sum"
+							}
+						}
+					}
+				},
+				group_by = new
+				{
+					weekStartedOn = new
+					{
+						date_histogram = new
+						{
+							calendar_interval = "week",
+							field = "startedOn"
+						}
+					}
+				}
+			},
+			sync = new
+			{
+				time = new
+				{
+					field = "lastActivity"
+				}
+			},
+			settings = new
+			{
+				docs_per_second = 200.0,
+				max_page_search_size = 200
+			}
+		};
+
+		protected override PreviewTransformRequest Initializer => new PreviewTransformRequest
+		{
+			Description = CallIsolatedValue,
+			Frequency = "1s",
+			Source = new TransformSource { Index = Index<Project>(), Query = new MatchAllQuery() },
+			Destination = new TransformDestination { Index = $"transform-{CallIsolatedValue}" },
+			Pivot = new TransformPivot
+			{
+				Aggregations =
+					new AverageAggregation("averageCommits", Field<Project>(f => f.NumberOfCommits)) &&
+					new ScriptedMetricAggregation("sumIntoMaster")
+					{
+						InitScript = new InlineScript("state.masterCommits = []"),
+						MapScript = new InlineScript("state.masterCommits.add(doc['branches.keyword'].contains('master')? 1 : 0)"),
+						CombineScript = new InlineScript("long sum = 0; for (s in state.masterCommits) { sum += s } return sum"),
+						ReduceScript = new InlineScript("long sum = 0; for (s in states) { sum += s } return sum")
+					},
+				GroupBy = new Dictionary<string, ISingleGroupSource>
+				{
+					{
+						"weekStartedOn",
+						new DateHistogramGroupSource() { Field = Field<Project>(f => f.StartedOn), CalendarInterval = DateInterval.Week }
+					}
+				}
+			},
+			Sync = new TransformSyncContainer(new TransformTimeSync { Field = Field<Project>(f => f.LastActivity) }),
+			Settings = new TransformSettings { MaxPageSearchSize = 200, DocsPerSecond = 200 }
+		};
+
+		protected override Func<PreviewTransformDescriptor<Project>, IPreviewTransformRequest> Fluent => f => f
+			.Description(CallIsolatedValue)
+			.Frequency(new Time(1, TimeUnit.Second))
+			.Source(s => s
+				.Index<Project>()
+				.Query(q => q.MatchAll())
+			)
+			.Destination(de => de
+				.Index($"transform-{CallIsolatedValue}")
+			)
+			.Pivot(p => p
+				.Aggregations(a => a
+					.Average("averageCommits", avg => avg
+						.Field(f => f.NumberOfCommits)
+					)
+					.ScriptedMetric("sumIntoMaster", sm => sm
+						.InitScript("state.masterCommits = []")
+						.MapScript("state.masterCommits.add(doc['branches.keyword'].contains('master')? 1 : 0)")
+						.CombineScript("long sum = 0; for (s in state.masterCommits) { sum += s } return sum")
+						.ReduceScript("long sum = 0; for (s in states) { sum += s } return sum")
+					)
+				)
+				.GroupBy(g => g
+					.DateHistogram("weekStartedOn", dh => dh
+						.Field(f => f.StartedOn)
+						.CalendarInterval(DateInterval.Week)
+					)
+				)
+			)
+			.Sync(sy => sy
+				.Time(t => t
+					.Field(f => f.LastActivity)
+				)
+			)
+			.Settings(s => s
+				.MaxPageSearchSize(200)
+				.DocsPerSecond(200)
+			);
+	}
+}