changed logic

Microsoft.Azure.Cosmos/src/Batch/BatchCore.cs

@@ -18,8 +18,6 @@ internal class BatchCore : TransactionalBatchInternal
 
         private readonly ContainerInternal container;
 
-        private List<ItemBatchOperation> operations;
-
         /// <summary>
         /// Initializes a new instance of the <see cref="BatchCore"/> class.
         /// </summary>
@@ -43,7 +41,7 @@ public override TransactionalBatch CreateItem<T>(
                 throw new ArgumentNullException(nameof(item));
             }
 
-            this.operations.Add(new ItemBatchOperation<T>(
+            this.AddOperation(new ItemBatchOperation<T>(
                     operationType: OperationType.Create,
                     operationIndex: this.operations.Count,
                     resource: item,
@@ -62,7 +60,7 @@ public override TransactionalBatch CreateItemStream(
                 throw new ArgumentNullException(nameof(streamPayload));
             }
 
-            this.operations.Add(new ItemBatchOperation(
+            this.AddOperation(new ItemBatchOperation(
                     operationType: OperationType.Create,
                     operationIndex: this.operations.Count,
                     resourceStream: streamPayload,
@@ -81,7 +79,7 @@ public override TransactionalBatch ReadItem(
                 throw new ArgumentNullException(nameof(id));
             }
 
-            this.operations.Add(new ItemBatchOperation(
+            this.AddOperation(new ItemBatchOperation(
                     operationType: OperationType.Read,
                     operationIndex: this.operations.Count,
                     id: id,
@@ -100,7 +98,7 @@ public override TransactionalBatch UpsertItem<T>(
                 throw new ArgumentNullException(nameof(item));
             }
 
-            this.operations.Add(new ItemBatchOperation<T>(
+            this.AddOperation(new ItemBatchOperation<T>(
                     operationType: OperationType.Upsert,
                     operationIndex: this.operations.Count,
                     resource: item,
@@ -119,7 +117,7 @@ public override TransactionalBatch UpsertItemStream(
                 throw new ArgumentNullException(nameof(streamPayload));
             }
 
-            this.operations.Add(new ItemBatchOperation(
+            this.AddOperation(new ItemBatchOperation(
                     operationType: OperationType.Upsert,
                     operationIndex: this.operations.Count,
                     resourceStream: streamPayload,
@@ -144,7 +142,7 @@ public override TransactionalBatch ReplaceItem<T>(
                 throw new ArgumentNullException(nameof(item));
             }
 
-            this.operations.Add(new ItemBatchOperation<T>(
+            this.AddOperation(new ItemBatchOperation<T>(
                     operationType: OperationType.Replace,
                     operationIndex: this.operations.Count,
                     id: id,
@@ -170,7 +168,7 @@ public override TransactionalBatch ReplaceItemStream(
                 throw new ArgumentNullException(nameof(streamPayload));
             }
 
-            this.operations.Add(new ItemBatchOperation(
+            this.AddOperation(new ItemBatchOperation(
                     operationType: OperationType.Replace,
                     operationIndex: this.operations.Count,
                     id: id,
@@ -190,7 +188,7 @@ public override TransactionalBatch DeleteItem(
                 throw new ArgumentNullException(nameof(id));
             }
 
-            this.operations.Add(new ItemBatchOperation(
+            this.AddOperation(new ItemBatchOperation(
                     operationType: OperationType.Delete,
                     operationIndex: this.operations.Count,
                     id: id,
@@ -236,7 +234,9 @@ public override Task<TransactionalBatchResponse> ExecuteAsync(
                     return executor.ExecuteAsync(trace,  cancellationToken);
                 },
                 openTelemetry: (response) => new OpenTelemetryResponse(
-                    responseMessage: response));
+                    responseMessage: response, 
+                    operationFlag: this.isHomogenousOperations, 
+                    operationName: this.lastItemBatchOperation.OperationType));
         }
 
         /// <summary>
@@ -251,7 +251,7 @@ public virtual TransactionalBatch PatchItemStream(
             Stream patchStream,
             TransactionalBatchPatchItemRequestOptions requestOptions = null)
         {
-            this.operations.Add(new ItemBatchOperation(
+            this.AddOperation(new ItemBatchOperation(
                 operationType: OperationType.Patch,
                 operationIndex: this.operations.Count,
                 id: id,
@@ -287,7 +287,7 @@ public override TransactionalBatch PatchItem(
 
             PatchSpec patchSpec = new PatchSpec(patchOperations, requestOptions);
 
-            this.operations.Add(new ItemBatchOperation<PatchSpec>(
+            this.AddOperation(new ItemBatchOperation<PatchSpec>(
                 operationType: OperationType.Patch,
                 operationIndex: this.operations.Count,
                 id: id,

Microsoft.Azure.Cosmos/src/Batch/TransactionalBatchInternal.cs

@@ -4,12 +4,34 @@
 
 namespace Microsoft.Azure.Cosmos
 {
+    using System.Collections.Generic;
     using System.IO;
     using System.Net;
     using System.Threading;
     using System.Threading.Tasks;
+    using Microsoft.Azure.Documents;
 
     internal abstract class TransactionalBatchInternal : TransactionalBatch
     {
+        protected List<ItemBatchOperation> operations;
+
+        internal bool isHomogenousOperations = false;
+
+        internal ItemBatchOperation lastItemBatchOperation = null;
+
+        protected void AddOperation(ItemBatchOperation itemBatchOperation)
+        {
+            this.operations.Add(itemBatchOperation);
+            if (this.operations.Count == 1)
+            {
+                this.lastItemBatchOperation = itemBatchOperation;
+            }
+            else
+            {
+                this.isHomogenousOperations = this.isHomogenousOperations 
+                    && this.lastItemBatchOperation.OperationType == itemBatchOperation.OperationType;
+                this.lastItemBatchOperation = itemBatchOperation;
+            }
+        }
     }
 }

Microsoft.Azure.Cosmos/src/Batch/TransactionalBatchResponse.cs

@@ -401,28 +401,6 @@ internal int GetBatchSize()
             return this.Operations.Count;
         }
 
-        internal OperationType? GetBatchOperationName()
-        {
-            HashSet<OperationType> operationNames = new ();
-
-            if (this.Operations == null)
-            {
-                return null;
-            }
-
-            foreach (ItemBatchOperation operation in this.Operations)
-            {
-                operationNames.Add(operation.OperationType);
-            }
-
-            if (operationNames.Count == 1)
-            {
-                return this.Operations[0].OperationType;
-            }
-
-            return null;
-        }
-
         /// <summary>
         /// Disposes the disposable members held by this class.
         /// </summary>

Microsoft.Azure.Cosmos/src/Telemetry/OpenTelemetry/OpenTelemetryResponse.cs

@@ -8,11 +8,12 @@ namespace Microsoft.Azure.Cosmos
     using System.IO;
     using System.Net;
     using Microsoft.Azure.Cosmos.Core.Trace;
+    using Microsoft.Azure.Documents;
     using Telemetry;
 
     internal sealed class OpenTelemetryResponse : OpenTelemetryAttributes
     {
-        internal OpenTelemetryResponse(TransactionalBatchResponse responseMessage)
+        internal OpenTelemetryResponse(TransactionalBatchResponse responseMessage, bool operationFlag, OperationType? operationName)
            : this(
                   statusCode: responseMessage.StatusCode,
                   requestCharge: OpenTelemetryResponse.GetHeader(responseMessage)?.RequestCharge,
@@ -24,7 +25,7 @@ internal OpenTelemetryResponse(TransactionalBatchResponse responseMessage)
                   activityId: OpenTelemetryResponse.GetHeader(responseMessage)?.ActivityId,
                   correlationId: OpenTelemetryResponse.GetHeader(responseMessage)?.CorrelatedActivityId,
                   batchSize: responseMessage.GetBatchSize(),
-                  batchOperationName: responseMessage.GetBatchOperationName())
+                  batchOperationName: operationFlag ? operationName : null )
         {
         }
 

Microsoft.Azure.Cosmos/tests/Microsoft.Azure.Cosmos.EmulatorTests/Tracing/CustomListener.cs

@@ -40,6 +40,7 @@ internal class CustomListener :
             "db.cosmosdb.connection_mode",
             "db.cosmosdb.operation_type",
             "db.cosmosdb.regions_contacted",
+            "db.cosmosdb.batch_size",
             "rntbd.sub_status_code",
             "rntbd.status_code",
             "error.type"

Microsoft.Azure.Cosmos/tests/Microsoft.Azure.Cosmos.Tests/Telemetry/OpenTelemetryRecorderTests.cs

@@ -107,7 +107,7 @@ public async Task CheckResponseCompatibility()
 
                 if (instance is TransactionalBatchResponse transactionInstance)
                 {
-                    _ = new OpenTelemetryResponse(transactionInstance);
+                    _ = new OpenTelemetryResponse(transactionInstance, false, null);
                 }
                 else if (instance is ResponseMessage responseMessageInstance)
                 {