stateMachinePoc.go

package main

import (
	"log"
	"time"
)

// State contains current state
type State struct {
	input []byte
}

// StateFn defines transition
type StateFn func(*State) StateFn

// NewPassState creates Pass state
func NewPassState(next StateFn) StateFn {
	return func(_ *State) StateFn {
		log.Println("[DEBUG] Entering pass state")
		log.Println("[DEBUG] Exiting pass state")
		return next
	}
}

// NewWaitDelayState creates Wait state
func NewWaitDelayState(next StateFn, delay time.Duration) StateFn {
	return func(_ *State) StateFn {
		log.Println("[DEBUG] Entering wait state")
		time.Sleep(delay)
		log.Println("[DEBUG] Exiting wait state")
		return next
	}
}

// Run state machine
func Run(startState StateFn, input []byte) {
	state := &State{input}
	for stateFn := startState; stateFn != nil; {
		stateFn = stateFn(state)
	}
}

func main() {

	state2 := NewPassState(nil)
	state1 := NewWaitDelayState(state2, time.Second*5)

	Run(state1, []byte{})
}