# README
Multi Progress Bar
mpb is a Go lib for rendering progress bars in terminal applications.
Features
- Multiple Bars: Multiple progress bars are supported
- Dynamic Total: Set total while bar is running
- Dynamic Add/Remove: Dynamically add or remove bars
- Cancellation: Cancel whole rendering process
- Predefined Decorators: Elapsed time, ewma based ETA, Percentage, Bytes counter
- Decorator's width sync: Synchronized decorator's width among multiple bars
Usage
Rendering single bar
package main
import (
"math/rand"
"time"
"github.com/vbauerster/mpb/v5"
"github.com/vbauerster/mpb/v5/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),
// override DefaultBarStyle, which 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(
decor.AverageETA(decor.ET_STYLE_GO, decor.WC{W: 4}), "done",
),
),
mpb.AppendDecorators(decor.Percentage()),
)
// simulating some work
max := 100 * time.Millisecond
for i := 0; i < total; i++ {
time.Sleep(time.Duration(rand.Intn(10)+1) * max / 10)
bar.Increment()
}
// wait for our bar to complete and flush
p.Wait()
}
Rendering multiple bars
var wg sync.WaitGroup
// pass &wg (optional), so p will wait for it eventually
p := mpb.New(mpb.WithWaitGroup(&wg))
total, numBars := 100, 3
wg.Add(numBars)
for i := 0; i < numBars; i++ {
name := fmt.Sprintf("Bar#%d:", i)
bar := p.AddBar(int64(total),
mpb.PrependDecorators(
// simple name decorator
decor.Name(name),
// decor.DSyncWidth bit enables column width synchronization
decor.Percentage(decor.WCSyncSpace),
),
mpb.AppendDecorators(
// replace ETA decorator with "done" message, OnComplete event
decor.OnComplete(
// ETA decorator with ewma age of 60
decor.EwmaETA(decor.ET_STYLE_GO, 60), "done",
),
),
)
// simulating some work
go func() {
defer wg.Done()
rng := rand.New(rand.NewSource(time.Now().UnixNano()))
max := 100 * time.Millisecond
for i := 0; i < total; i++ {
// start variable is solely for EWMA calculation
// EWMA's unit of measure is an iteration's duration
start := time.Now()
time.Sleep(time.Duration(rng.Intn(10)+1) * max / 10)
bar.Increment()
// we need to call DecoratorEwmaUpdate to fulfill ewma decorator's contract
bar.DecoratorEwmaUpdate(time.Since(start))
}
}()
}
// Waiting for passed &wg and for all bars to complete and flush
p.Wait()
Dynamic total
Complex example
Bytes counters
# Functions
AppendDecorators let you inject decorators to the bar's right side.
BarExtender is an option to extend bar to the next new line, with arbitrary output.
BarFillerClearOnComplete clears bar's filler on complete event.
BarFillerMiddleware provides a way to augment default BarFiller.
BarFillerOnComplete replaces bar's filler with message, on complete event.
BarFillerTrim bar filler is rendered with leading and trailing space like ' [===] ' by default.
BarID sets bar id.
BarNoPop disables bar pop out of container.
BarOptOn returns option when condition evaluates to true.
BarPriority sets bar's priority.
BarQueueAfter queues this (being constructed) bar to relplace runningBar after it has been completed.
BarRemoveOnComplete removes both bar's filler and its decorators on complete event.
BarReverse reverse mode, bar will progress from right to left.
BarStyle overrides mpb.DefaultBarStyle which is "[=>-]<+".
BarWidth sets bar width independent of the container.
ContainerOptOn returns option when condition evaluates to true.
MakeFillerTypeSpecificBarOption makes BarOption specific to Filler's actual type.
New creates new Progress container instance.
NewBarFiller constucts mpb.BarFiller, to be used with *Progress.Add(...) *Bar method.
NewSpinnerFiller constucts mpb.BarFiller, to be used with *Progress.Add(...) *Bar method.
NewWithContext creates new Progress container instance with provided context.
PopCompletedMode will pop and stop rendering completed bars.
PrependDecorators let you inject decorators to the bar's left side.
SpinnerStyle sets custom spinner style.
TrimSpace is an alias to BarFillerTrim.
WithDebugOutput sets debug output.
WithManualRefresh disables internal auto refresh time.Ticker.
WithOutput overrides default os.Stdout output.
WithRefreshRate overrides default 120ms refresh rate.
WithRenderDelay delays rendering.
WithShutdownNotifier provided chanel will be closed, after all bars have been rendered.
WithWaitGroup provides means to have a single joint point.
WithWidth sets container width.
# Constants
DefaultBarStyle is a string containing 7 runes.
SpinnerAlignment kinds.
SpinnerAlignment kinds.
SpinnerAlignment kinds.
# Variables
DefaultSpinnerStyle is a slice of strings, which makes a spinner.
# Interfaces
BarFiller interface.
# Type aliases
BarFillerFunc is function type adapter to convert function into BarFiller.
BarOption is a function option which changes the default behavior of a bar.
ContainerOption is a function option which changes the default behavior of progress container, if passed to mpb.New(...ContainerOption).
SpinnerAlignment enum.