exponential-backoff

exponential-backoff.go

package main

import (
	"bufio"
	"fmt"
	"math"
	"math/rand"
	"os"
	"strconv"
	"time"
)

func exitWithError(err error) {
	fmt.Println(err)
	os.Exit(1)
}

func main() {
	fmt.Println("* exponential backoff calculator")
	scanner := bufio.NewScanner(os.Stdin)
	sz := 64

	fmt.Print("steps: ")
	scanner.Scan()
	steps, err := strconv.ParseFloat(scanner.Text(), sz)
	if err != nil {
		exitWithError(err)
	}

	fmt.Print("duration: ")
	scanner.Scan()
	duration, err := strconv.ParseFloat(scanner.Text(), sz)
	if err != nil {
		exitWithError(err)
	}

	fmt.Print("factor: ")
	scanner.Scan()
	factor, err := strconv.ParseFloat(scanner.Text(), sz)
	if err != nil {
		exitWithError(err)
	}

	fmt.Print("jitter: ")
	scanner.Scan()
	jitter, err := strconv.ParseFloat(scanner.Text(), sz)
	if err != nil {
		exitWithError(err)
	}

	value := 0.0
	rand.Seed(time.Now().UnixNano())
	for i := uint(0); i < uint(steps); i++ {
		fmt.Printf("step: %v, value: %v\n", i, math.Round(value*100)/100)
		value = value*factor + duration + rand.Float64()*jitter*duration
	}
}