mpb 进度条
最后更新于：2022-04-02 02:39:12
[TOC]
> [vbauerster/mpb](https://github.com/vbauerster/mpb)
## 实例
### 单进度条
```
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()
}
```
### 多进度条
```
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()
```
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