CHECKOUT FLOW

SketchSystems.spec

CHECKOUT FLOW
  View bag*
    checkout -> Checkout summary
  Checkout summary
    buy -> Reserve stock
  Reserve stock
    Lock product*
      locked -> Insert purchase record
      failed -> Error
    Insert purchase record
      inserted -> Unlock product
      failed -> Unlock product with Error
    Create shipping mandate
      not needed -> Unlock product
      created -> Unlock product
      failed -> Rollback
    Rollback
      done -> Unlock product
    Unlock product
      unlocked -> User approve payment
    Unlock product with Error
      unlocked -> Error
  User approve payment
    approved -> Attempt to complete payment
    not approved -> Cancel checkout
    error -> Cancel checkout with Error
  Attempt to complete payment
    completed -> Checkout succeeded
    indeterminate -> Attempt to complete payment
    retryable error -> Attempt to complete payment
    fatal error -> Cancel checkout with Error
  Checkout succeeded
    Broadcast event
  
  Cancel checkout
    cancelled -> View bag
  Cancel checkout with Error
    cancelled -> Error
 
  Error

SketchSystems_prototype.js

function render(model){
  let current_state_name = model.active_states[0].name;
  return $("h1",
           {style: {color: "darkBlue"}},
           `The current state is: ${current_state_name}`);
}

from this tool: https://sketch.systems/