Hello @Vitaliy Serdtsev 

Thank you for pointing the %CSP.SessionEvents class to capture the end of request. However, my requirement is to intercept  the written API response by class method before it's sent to UI.

Thank you!

Hello @Evgeny Shvarov

Unfortunately, when the %JSONFIELDNAME parameter is not explicitly defined, the JSON adaptor treats the property name as a constant, making it fixed and case-sensitive.

However, you can define a custom mapping using an XData block to control how properties are mapped to JSON fields. This provides greater flexibility, and you can even use both %JSONFIELDNAME and XData mappings within the same class.

Example: Custom Mapping with XData

XData OnlyLowercaseTopLevel
{
  <Mapping xmlns="http://www.intersystems.com/jsonmapping">
    <Property Name="Name" FieldName="eventName"/>
    <Property Name="Location" Include="INPUTONLY"/>
  </Mapping>
}

• Do obj.%JSONImport(dao) Default import (uses standard property names)
• Do obj.%JSONImport(dao, "OnlyLowercaseTopLevel")Import using a custom mapping