main.go

package main

import (
	"math/rand"
	"time"

	"github.com/mikewiacek/mpb"
	"github.com/mikewiacek/mpb/decor"
)

func main() {
	// initialize progress container, with custom width
	p := mpb.New(mpb.WithWidth(64))

	total := 100
	name := "Single Bar:"
	// adding a single bar, which will inherit container's width
	bar := p.AddBar(int64(total),
		// set custom bar style, default one is "[=>-]"
		mpb.BarStyle("╢▌▌░╟"),
		mpb.PrependDecorators(
			// display our name with one space on the right
			decor.Name(name, decor.WC{W: len(name) + 1, C: decor.DidentRight}),
			// replace ETA decorator with "done" message, OnComplete event
			decor.OnComplete(
				// ETA decorator with ewma age of 60, and width reservation of 4
				decor.EwmaETA(decor.ET_STYLE_GO, 60, decor.WC{W: 4}), "done",
			),
		),
		mpb.AppendDecorators(decor.Percentage()),
	)
	// simulating some work
	max := 100 * time.Millisecond
	for i := 0; i < total; i++ {
		start := time.Now()
		time.Sleep(time.Duration(rand.Intn(10)+1) * max / 10)
		// ewma based decorators require work duration measurement
		bar.IncrBy(1, time.Since(start))
	}
	// wait for our bar to complete and flush
	p.Wait()
	p.Wait()
}