The two interfaces Elevator and ElevatorController have been implemented for a Tingco-based elevator shaft.
They can be found in com.tingco.codechallenge.elevator.api.tingco together with a shaft engine to keep the wheels turning.
The engine uses a speed variable, configured as described below, to determine how long a tick is.
Each tick a busy elevator decides what action to take, if any.
application.properties has a few configuration settings: the number of floors and elevators as well as their speed.
Safety first! Run mvn test to verify that the elevators are working as expected.
Feel free to have a look at the tests as they serve as documentation for what features are implemented.
Start the app with mvn spring-boot:run
There are a few endpoints to control the elevators:
/api/elevators/config GET to get the number of elevators and floors used in this elevator shaft, as well as their speed.
/api/elevators GET to get a list of all elevators and their info.
/api/elevators/floors/{floor number} POST with an empty body to request an elevator to the floor number.
/api/elevators/{elevator id} PUT with a body specifying the floor to move an elevator to a new floor.
/api/elevators/{elevator id} DELETE to release the elevator with the given id.
Some examples using curl:
curl -v "http://localhost:8080/api/elevators/config"
curl -v "http://localhost:8080/api/elevators"
curl -v "http://localhost:8080/api/elevators/floors/4" -X POST --data ""
curl -v "http://localhost:8080/api/elevators/3" -H "Content-Type: application/json" -X PUT --data '{"addressedFloor": 1}'
curl -v "http://localhost:8080/api/elevators/3" -X DELETE
Read the log messages written to stdout to verify the elevators are behaving like expected.
Life as an elevator builder never ends. I have sprinkled my code with some todos with my thoughts on what would be
good to have a look at in the future.
I had begun to work on a React frontend using Spring's websockets support for a more appealing user experience.
However, time got in the way and so I went with the safe option: REST and logging.
Another thought was to put in a SQLite and use Spring Data to persist the elevator state between runs.