Elevator Simulator 2019

This is an attempt at this elevator themed kata: [https://gist.github.com/mattflo/4669508] built using Reactjs

Getting started

• install nodejs
• download repo
• run npm i
• run npm start

Breaking problem down

• an elevator responds to calls containing a source floor and direction
  • elevator.goToFloor(floorNumber: int)
  • app needs stack containing requests: {sourceFloor: int, direction: string}
  • need eventEmitted for "arrived-at-floor"
  • passengers popped of floor.passengers array and on to elevator.passengers array
• an elevator delivers passengers to requested floors
  • need second request queue for passengers on elevator
• an elevator doesn't respond immediately. consider options to simulate time
  • setTimeout() to begin with. Add animation if time allows
• elevator calls are queued not necessarily FIFO
  • need "passing-floor" event to allow app to check if either request queue contains a request for that floor so passengers can get on/off
• you may validate passenger floor requests
  • ignore dupplicate requests for both stacks
• you may implement current floor monitor
  • elevator.getCurrentFloor()?
• you may implement direction arrows
  • button compenents for each floor component
• you may implement doors (opening and closing)
• you may implement DING!
• there can be more than one elevator
  • come back to this last...

Issues with implementation

I initially thought Reactjs would be great for implementing this Kata, however due to my inexperience I ran into some unforseen issues:

• native react does not support changing complicated state well.
• all state had to be stored and changed in parent
• Couldn't encapsulte behaviour within objects as any changes to state wouldn't trigger render(); defeating one of the main features of react
• The main App component became quite monolithic due to the above making it difficult keep track of elevator logic

I shot myself in the foot a little by choosing to build this in a framework I'm still getting to grips with. :(