Core Platform Team/Initiative/Reduce Extension Interface Surface Area/Epics, User Stories, and Requirements

< Reduce Extension Interface Surface Area

Develop the product plan
Analysis and Design:
- Action and filter hooks:
  - Approve RFC for action and filter hooks
  - Enumerate all current hook points, and analyze their usage in extensions
  - Categorize current hooks as action and/or filter hooks and map parameters (identify any parameters that need to change/create new parameter types)
  - Develop deprecation and migration plan
- Access to core:
  - Define acceptable access to global state
  - Analyze which core code is called by extensions
  - Analyze what global state is accessed by extensions
  - Analyze which core classes are subclassed by extensions
  - Identify areas of core code that extensions should not access and identify alternatives
  - For each area of improvement identified:
    - Make proposal for improvement (possible RFC)
    - Collect feedback from stakeholders
    - Develop deprecation and migration plan
Create development plan
Development:
- Implement the action and filter hook interfaces dictated in the RFC
- Provide developer facing documentation for migration of for new hooks
- Migrate extensions to new hooks
- Implement new core interfaces per each proposal for improvement
- Mark core code that is internal and may not be accessed by extensions (may require tool support)
- Mark core classes that may be subclassed by extensions (may require tool support)
- Provide developer facing documentation for migration to new core interfaces
- Migrate extensions to new core interfaces
- Deprecate then remove old hooks and interfaces