Research Notes

What I want to design for

• Avoid Polluting application level code with trivial conditions
• Move pre-conditions to application edge, so domain can focus on business logic
• Domain is always in valid state
• Domain doesn't have to be as defensive
• NOT Putting a guard class or pre-condition inside every single method being dealt with
• NOT Copy and pasting guard clause in every single area
• Custom predicates for guarding to avoid nesting
• Chain together series of processing steps in an organized way
• Passing a callback into the guard clause, if it passed execute the callback
• SRP, each stage focuses on a specific task
• Stages can be re-used and modularly moved
• Allows stage independent testing
• Result from previous task leveraged in next task
• Approach
  • Pipeline - a chain of steps
  • Step - a specific task
  • Data - information that passes between steps
• Russian doll model example → Middleware
  • One filter causes the next filter
  • Same uniform interfaces
  • Call stack originates from the beggaring
  • You can short circuit along the way
    • return