.Net: Fixed JSON schema name in Structured Outputs for generic types (m…

…icrosoft#9490)

### Motivation and Context

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Resolves: microsoft#9416

When C# type is passed as a response format to OpenAI chat completion
service, we use the type name as [JSON schema
name](https://platform.openai.com/docs/api-reference/chat/create#chat-create-response_format).
When the type is generic, its name will contain characters that are not
allowed in JSON schema name according to OpenAI API. This PR fixes the
issue by replacing invalid characters with empty string.

### Contribution Checklist

<!-- Before submitting this PR, please make sure: -->

- [x] The code builds clean without any errors or warnings
- [x] The PR follows the [SK Contribution
Guidelines](https://github.com/microsoft/semantic-kernel/blob/main/CONTRIBUTING.md)
and the [pre-submission formatting
script](https://github.com/microsoft/semantic-kernel/blob/main/CONTRIBUTING.md#development-scripts)
raises no violations
- [x] All unit tests pass, and I have added new tests where possible
- [x] I didn't break anyone 😄

dotnet/src/Connectors/Connectors.OpenAI.UnitTests/Services/OpenAIChatCompletionServiceTests.cs

@@ -1179,9 +1179,13 @@ public async Task GetChatMessageContentsSendsValidJsonSchemaForStructuredOutputs
     }
 
     [Theory]
-    [InlineData(typeof(TestStruct))]
-    [InlineData(typeof(TestStruct?))]
-    public async Task GetChatMessageContentsSendsValidJsonSchemaWithStruct(Type responseFormatType)
+    [InlineData(typeof(TestStruct), "TestStruct")]
+    [InlineData(typeof(TestStruct?), "TestStruct")]
+    [InlineData(typeof(TestStruct<string>), "TestStructString")]
+    [InlineData(typeof(TestStruct<string>?), "TestStructString")]
+    [InlineData(typeof(TestStruct<List<float>>), "TestStructListSingle")]
+    [InlineData(typeof(TestStruct<List<float>>?), "TestStructListSingle")]
+    public async Task GetChatMessageContentsSendsValidJsonSchemaWithStruct(Type responseFormatType, string expectedSchemaName)
     {
         // Arrange
         var executionSettings = new OpenAIPromptExecutionSettings { ResponseFormat = responseFormatType };
@@ -1204,7 +1208,7 @@ public async Task GetChatMessageContentsSendsValidJsonSchemaWithStruct(Type resp
         var requestResponseFormat = requestJsonElement.GetProperty("response_format");
 
         Assert.Equal("json_schema", requestResponseFormat.GetProperty("type").GetString());
-        Assert.Equal("TestStruct", requestResponseFormat.GetProperty("json_schema").GetProperty("name").GetString());
+        Assert.Equal(expectedSchemaName, requestResponseFormat.GetProperty("json_schema").GetProperty("name").GetString());
         Assert.True(requestResponseFormat.GetProperty("json_schema").GetProperty("strict").GetBoolean());
 
         var schema = requestResponseFormat.GetProperty("json_schema").GetProperty("schema");
@@ -1219,8 +1223,8 @@ public async Task GetChatMessageContentsSendsValidJsonSchemaWithStruct(Type resp
             schema.GetProperty("required")[1].GetString(),
         };
 
-        Assert.Contains("TextProperty", requiredParentProperties);
-        Assert.Contains("NumericProperty", requiredParentProperties);
+        Assert.Contains("Property1", requiredParentProperties);
+        Assert.Contains("Property2", requiredParentProperties);
     }
 
     [Fact]
@@ -1571,9 +1575,16 @@ private sealed class MathReasoningStep
 
     private struct TestStruct
     {
-        public string TextProperty { get; set; }
+        public string Property1 { get; set; }
 
-        public int? NumericProperty { get; set; }
+        public int? Property2 { get; set; }
+    }
+
+    private struct TestStruct<TProperty>
+    {
+        public TProperty Property1 { get; set; }
+
+        public int? Property2 { get; set; }
     }
 #pragma warning restore CS8618, CA1812
 }

dotnet/src/Connectors/Connectors.OpenAI/Core/ClientCore.ChatCompletion.cs

@@ -573,7 +573,28 @@ private static ChatResponseFormat GetJsonSchemaResponseFormat(Type formatObjectT
         var schema = KernelJsonSchemaBuilder.Build(type, configuration: s_jsonSchemaMapperConfiguration);
         var schemaBinaryData = BinaryData.FromString(schema.ToString());
 
-        return ChatResponseFormat.CreateJsonSchemaFormat(type.Name, schemaBinaryData, jsonSchemaIsStrict: true);
+        var typeName = GetTypeName(type);
+
+        return ChatResponseFormat.CreateJsonSchemaFormat(typeName, schemaBinaryData, jsonSchemaIsStrict: true);
+    }
+
+    /// <summary>
+    /// Returns a type name concatenated with generic argument type names if they exist.
+    /// </summary>
+    private static string GetTypeName(Type type)
+    {
+        if (!type.IsGenericType)
+        {
+            return type.Name;
+        }
+
+        // If type is generic, base name is followed by ` character.
+        string baseName = type.Name.Substring(0, type.Name.IndexOf('`'));
+
+        Type[] typeArguments = type.GetGenericArguments();
+        string argumentNames = string.Concat(Array.ConvertAll(typeArguments, GetTypeName));
+
+        return $"{baseName}{argumentNames}";
     }
 
     /// <summary>Checks if a tool call is for a function that was defined.</summary>