Add score_mode option to Rescore

Author: gmarz

src/Nest/DSL/Rescore/RescoreQueryDescriptor.cs

@@ -16,13 +16,17 @@ public interface IRescoreQuery
 
 		[JsonProperty("rescore_query_weight")]
 		double? RescoreQueryWeight { get; set; }
+
+		[JsonProperty("score_mode")]
+		ScoreMode? ScoreMode { get; set; }
 	}
 
 	public class RescoreQuery : IRescoreQuery
 	{
 		public IQueryContainer Query { get; set; }
 		public double? QueryWeight { get; set; }
 		public double? RescoreQueryWeight { get; set; }
+		public ScoreMode? ScoreMode { get; set; }
 	}
 
 	public class RescoreQueryDescriptor<T> : IRescoreQuery where T : class
@@ -35,6 +39,8 @@ public class RescoreQueryDescriptor<T> : IRescoreQuery where T : class
 
 		double? IRescoreQuery.RescoreQueryWeight { get; set; }
 
+		ScoreMode? IRescoreQuery.ScoreMode { get; set; }
+
 		public virtual RescoreQueryDescriptor<T> QueryWeight(double queryWeight)
 		{
 			Self.QueryWeight = queryWeight;
@@ -47,6 +53,12 @@ public virtual RescoreQueryDescriptor<T> RescoreQueryWeight(double rescoreQueryW
 			return this;
 		}
 
+		public virtual RescoreQueryDescriptor<T> ScoreMode(ScoreMode scoreMode)
+		{
+			Self.ScoreMode = scoreMode;
+			return this;
+		}
+
 		public virtual RescoreQueryDescriptor<T> Query(Func<QueryDescriptor<T>, QueryContainer> query)
 		{
 			query.ThrowIfNull("query");

src/Tests/Nest.Tests.Unit/Search/Rescoring/RescoreSerializes.json

@@ -12,10 +12,11 @@
         }
       },
       "query_weight": 1.0,
-      "rescore_query_weight": 2.0
+      "rescore_query_weight": 2.0,
+      "score_mode": "multiply"
     }
   },
   "query": {
-    "match_all": {}
+    "match_all": { }
   },
-}
+}

src/Tests/Nest.Tests.Unit/Search/Rescoring/RescoreTests.cs

@@ -29,6 +29,7 @@ public void RescoreSerializes()
 					.RescoreQuery(rq=>rq
 						.QueryWeight(1.0)
 						.RescoreQueryWeight(2.0)
+						.ScoreMode(ScoreMode.Multiply)
 						.Query(q=>q.Term(p=>p.Name, "nest"))
 					)
 				);