SystemTextJsonSerializer: Adds UseSystemTextJsonSerializerWithOptions in CosmosClientOptions to Set the Default STJ Serializer

Microsoft.Azure.Cosmos/src/CosmosClientOptions.cs

@@ -392,6 +392,19 @@ public ConnectionMode ConnectionMode
         /// <seealso cref="ItemRequestOptions.EnableContentResponseOnWrite"/>
         /// <seealso cref="TransactionalBatchItemRequestOptions.EnableContentResponseOnWrite"/>
         public bool? EnableContentResponseOnWrite { get; set; }
+
+        /// <summary>
+        /// Gets or sets the boolean flag to indicate if the default STJ serializer <see cref="CosmosSystemTextJsonSerializer"/> needed to be
+        /// used for JSON serialization.
+        /// </summary>
+        /// <remarks>
+        /// Note that, if this flag is set to true, then any custom seriliazer provided will be disregarded and overridden with the
+        /// default STJ serializer <see cref="CosmosSystemTextJsonSerializer"/>.
+        /// </remarks>
+        /// <value>
+        /// The default value is false
+        /// </value>
+        public bool UseSystemTextJsonForSerialization { get; set; } = false;
 
         /// <summary>
         /// Gets or sets the advanced replica selection flag. The advanced replica selection logic keeps track of the replica connection

Microsoft.Azure.Cosmos/src/Fluent/CosmosClientBuilder.cs

@@ -726,6 +726,16 @@ internal CosmosClientBuilder WithPartitionLevelFailoverEnabled()
             this.clientOptions.EnablePartitionLevelFailover = true;
             return this;
         }
+
+        /// <summary>
+        /// Enables the usage of <see cref="CosmosSystemTextJsonSerializer"/> as the default
+        /// serializer.
+        /// </summary>
+        internal CosmosClientBuilder WithSystemTextJsonSerializerEnabled()
+        {
+            this.clientOptions.UseSystemTextJsonForSerialization = true;
+            return this;
+        }
 
         /// <summary>
         /// Enables SDK to inject fault. Used for testing applications.  

Microsoft.Azure.Cosmos/src/Resource/ClientContextCore.cs

@@ -128,6 +128,12 @@ internal static CosmosClientContext Create(
                 requestInvokerHandler = clientPipelineBuilder.Build();
             }
 
+            if (clientOptions.UseSystemTextJsonForSerialization)
+            {
+                clientOptions.Serializer = new CosmosSystemTextJsonSerializer(
+                    new System.Text.Json.JsonSerializerOptions());
+            }
+
             CosmosSerializerCore serializerCore = CosmosSerializerCore.Create(
                 clientOptions.Serializer,
                 clientOptions.SerializerOptions);

Microsoft.Azure.Cosmos/tests/Microsoft.Azure.Cosmos.EmulatorTests/Linq/LinqAggregateCustomSerializationBaseline.cs

@@ -29,7 +29,6 @@ public class LinqAggregateCustomSerializationBaseline : BaselineTests<LinqAggreg
         private static Cosmos.Database testDb;
         private static Container testContainer;
 
-        private static CosmosSerializer stjCosmosSerializer;
         private static CosmosClient stjClient;
         private static Cosmos.Database testDbSTJ;
         private static Container testContainerSTJ;
@@ -64,10 +63,8 @@ public async static Task Initialize(TestContext textContext)
             testDb = await client.CreateDatabaseAsync(dbName);
             testContainer = testDb.CreateContainerAsync(new ContainerProperties(id: Guid.NewGuid().ToString(), partitionKeyPath: "/Pk")).Result;
 
-            stjCosmosSerializer = new CosmosSystemTextJsonSerializer(new JsonSerializerOptions());
-
             stjClient = TestCommon.CreateCosmosClient((cosmosClientBuilder)
-                => cosmosClientBuilder.WithCustomSerializer(stjCosmosSerializer));
+                => cosmosClientBuilder.WithSystemTextJsonSerializerEnabled());
 
             // Set a callback to get the handle of the last executed query to do the verification
             // This is neede because aggregate queries return type is a scalar so it can't be used 

Microsoft.Azure.Cosmos/tests/Microsoft.Azure.Cosmos.EmulatorTests/LinqTranslationWithCustomSerializerBaseline.cs

@@ -57,7 +57,8 @@ public async static Task Initialize(TestContext textContext)
             TestDb = await CosmosClient.CreateDatabaseAsync(dbName);
 
             CosmosDefaultSTJClient = TestCommon.CreateCosmosClient((cosmosClientBuilder)
-                => cosmosClientBuilder.WithCustomSerializer(new CosmosSystemTextJsonSerializer(new JsonSerializerOptions())));
+                => cosmosClientBuilder.WithSystemTextJsonSerializerEnabled(),
+                useCustomSeralizer: false);
 
             string dbNameSTJ = $"{nameof(LinqTranslationBaselineTests)}-{Guid.NewGuid():N}";
             TestDbSTJDefault = await CosmosDefaultSTJClient.CreateDatabaseAsync(dbNameSTJ);

Microsoft.Azure.Cosmos/tests/Microsoft.Azure.Cosmos.Tests/Contracts/DotNetSDKAPI.json

@@ -2711,11 +2711,23 @@
           ],
           "MethodInfo": "Boolean get_LimitToEndpoint();IsAbstract:False;IsStatic:False;IsVirtual:False;IsGenericMethod:False;IsConstructor:False;IsFinal:False;"
         },
+        "Boolean get_UseSystemTextJsonForSerialization()[System.Runtime.CompilerServices.CompilerGeneratedAttribute()]": {
+          "Type": "Method",
+          "Attributes": [
+            "CompilerGeneratedAttribute"
+          ],
+          "MethodInfo": "Boolean get_UseSystemTextJsonForSerialization();IsAbstract:False;IsStatic:False;IsVirtual:False;IsGenericMethod:False;IsConstructor:False;IsFinal:False;"
+        },
         "Boolean LimitToEndpoint": {
           "Type": "Property",
           "Attributes": [],
           "MethodInfo": "Boolean LimitToEndpoint;CanRead:True;CanWrite:True;Boolean get_LimitToEndpoint();IsAbstract:False;IsStatic:False;IsVirtual:False;IsGenericMethod:False;IsConstructor:False;IsFinal:False;Void set_LimitToEndpoint(Boolean);IsAbstract:False;IsStatic:False;IsVirtual:False;IsGenericMethod:False;IsConstructor:False;IsFinal:False;"
         },
+        "Boolean UseSystemTextJsonForSerialization": {
+          "Type": "Property",
+          "Attributes": [],
+          "MethodInfo": "Boolean UseSystemTextJsonForSerialization;CanRead:True;CanWrite:True;Boolean get_UseSystemTextJsonForSerialization();IsAbstract:False;IsStatic:False;IsVirtual:False;IsGenericMethod:False;IsConstructor:False;IsFinal:False;Void set_UseSystemTextJsonForSerialization(Boolean);IsAbstract:False;IsStatic:False;IsVirtual:False;IsGenericMethod:False;IsConstructor:False;IsFinal:False;"
+        },
         "Int32 GatewayModeMaxConnectionLimit": {
           "Type": "Property",
           "Attributes": [],
@@ -3165,6 +3177,13 @@
           ],
           "MethodInfo": "Void set_TokenCredentialBackgroundRefreshInterval(System.Nullable`1[System.TimeSpan]);IsAbstract:False;IsStatic:False;IsVirtual:False;IsGenericMethod:False;IsConstructor:False;IsFinal:False;"
         },
+        "Void set_UseSystemTextJsonForSerialization(Boolean)[System.Runtime.CompilerServices.CompilerGeneratedAttribute()]": {
+          "Type": "Method",
+          "Attributes": [
+            "CompilerGeneratedAttribute"
+          ],
+          "MethodInfo": "Void set_UseSystemTextJsonForSerialization(Boolean);IsAbstract:False;IsStatic:False;IsVirtual:False;IsGenericMethod:False;IsConstructor:False;IsFinal:False;"
+        },
         "Void set_WebProxy(System.Net.IWebProxy)": {
           "Type": "Method",
           "Attributes": [],

Microsoft.Azure.Cosmos/tests/Microsoft.Azure.Cosmos.Tests/CosmosClientOptionsUnitTests.cs

@@ -13,6 +13,7 @@ namespace Microsoft.Azure.Cosmos.Tests
     using System.Net.Security;
     using System.Security.Cryptography;
     using System.Security.Cryptography.X509Certificates;
+    using System.Text;
     using global::Azure.Core;
     using Microsoft.Azure.Cosmos.Fluent;
     using Microsoft.Azure.Documents;
@@ -476,6 +477,25 @@ public void UserAgentContainsEnvironmentInformation()
             Assert.AreEqual(userAgentSuffix, connectionPolicy.UserAgentSuffix);
             Assert.IsTrue(connectionPolicy.UserAgentContainer.UserAgent.StartsWith(expectedValue));
             Assert.IsTrue(connectionPolicy.UserAgentContainer.UserAgent.EndsWith(userAgentSuffix));
+        }
+
+        [TestMethod]
+        public void ValidateThatCustomSerializerGetsOverriddenWhenSTJSerializerEnabled()
+        {
+            CosmosClientOptions options = new CosmosClientOptions()
+            {
+                Serializer = new CosmosJsonDotNetSerializer()
+            };
+
+            options.UseSystemTextJsonForSerialization = true;
+
+            CosmosClient client = new(
+                "https://fake-account.documents.azure.com:443/",
+                Convert.ToBase64String(Encoding.UTF8.GetBytes(Guid.NewGuid().ToString())),
+                options
+            );
+
+            Assert.AreEqual(typeof(CosmosSystemTextJsonSerializer), client.ClientOptions.Serializer.GetType());
         }
 
         [TestMethod]
@@ -500,7 +520,7 @@ public void ThrowOnCustomSerializerWithSerializerOptions()
             };
 
             options.Serializer = new CosmosJsonDotNetSerializer();
-        }
+        }
 
         [TestMethod]
         [ExpectedException(typeof(ArgumentNullException))]