Update mongodb

Src/Asp.NetCore2/MongoDb.Ado.data/ExecuteDbDataReaderItems/DbDataReaderFactory.cs

@@ -0,0 +1,33 @@
+using MongoDB.Bson;
+using MongoDB.Bson.Serialization.Serializers;
+using MongoDB.Driver;
+using System;
+using System.Collections.Generic;
+using System.Data.Common;
+using System.Text;
+
+namespace MongoDb.Ado.data
+{
+    public class DbDataReaderFactory
+    {
+        public DbDataReader Handle(string operation, IMongoCollection<BsonDocument> collection, string json)
+        {
+            var doc = MongoDB.Bson.Serialization.BsonSerializer.Deserialize<BsonValue>(json);
+            IQueryHandler queryHandler = null;
+            if (operation == "find")
+            {
+                queryHandler = new QueryFindHandler();
+            }
+            else if (operation == "aggregate")
+            {
+                queryHandler = new QueryAggregateHandler();
+            }
+            else 
+            {
+                throw new NotSupportedException($" NotSupportedException: {operation} ");
+            }
+            return queryHandler.Find(collection, doc);
+        }
+
+    }
+}