Swagger input generator is handling SerializationFormat on properties differently from the typespec generator

[ArcturusZhang]

This difference leads an ugly workaround on sample generator.

Fixing it here might not be worthy, creating this issue to track the issue.

Issue:
In typespec input, models are created by ModelProvider class. The properties inside this class will have SerializationFormat property properly assigned.
But in swagger input, models are created by SchemaObjectType class. The properties inside this class also have this SerializationFormat property, but its value is always Default.

Since now in the generator, only HLC and mgmt have some project using swagger as input, and HLC does not have a sample generator, this issue only impacts mgmt plane.

[live1206]

For TypeSpec input, right now MPG convert CodeModel into InputNamespace, but still processing with SchemaObjectType instead of ModelTypeProvider, will it also cause SerializationFormat missing?

[ArcturusZhang]

For TypeSpec input, right now MPG convert CodeModel into InputNamespace, but still processing with SchemaObjectType instead of ModelTypeProvider, will it also cause SerializationFormat missing?

we lose this information in SchemaObjectType.
This is how it is done:
In ModelTypeProvider, we construct the properties using this ctor:

autorest.csharp/src/AutoRest.CSharp/Common/Output/Models/Types/ObjectTypeProperty.cs

Line 23 in ac353ca

public ObjectTypeProperty(FieldDeclaration field, InputModelProperty? inputModelProperty)

In SchemaObjectType, we construct the properties using this ctor:

autorest.csharp/src/AutoRest.CSharp/Common/Output/Models/Types/ObjectTypeProperty.cs

Line 38 in ac353ca

public ObjectTypeProperty(MemberDeclarationOptions declaration, string parameterDescription, bool isReadOnly, InputModelProperty? inputModelProperty, CSharpType? valueType = null, bool optionalViaNullability = false)

In the second ctor, there is no input parameter of SerializationFormat, therefore it is always Default.
We need the serialization format when writing the sample values, for example we need to know, if the property is date-time, and we have a value 2024-11-21, how we assign this value to the property. But since the SerializationFormat is missing in the property, it is tricky to restore it.