packer-cn/vendor/github.com/cheggaaa/pb/README.md

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# Terminal progress bar for Go
Simple progress bar for console programs.
Please check the new version https://github.com/cheggaaa/pb/tree/v2 (currently, it's beta)
## Installation
```
go get gopkg.in/cheggaaa/pb.v1
```
## Usage
```Go
package main
import (
"gopkg.in/cheggaaa/pb.v1"
"time"
)
func main() {
count := 100000
bar := pb.StartNew(count)
for i := 0; i < count; i++ {
bar.Increment()
time.Sleep(time.Millisecond)
}
bar.FinishPrint("The End!")
}
```
Result will be like this:
```
> go run test.go
37158 / 100000 [================>_______________________________] 37.16% 1m11s
```
## Customization
```Go
// create bar
bar := pb.New(count)
// refresh info every second (default 200ms)
bar.SetRefreshRate(time.Second)
// show percents (by default already true)
bar.ShowPercent = true
// show bar (by default already true)
bar.ShowBar = true
// no counters
bar.ShowCounters = false
// show "time left"
bar.ShowTimeLeft = true
// show average speed
bar.ShowSpeed = true
// sets the width of the progress bar
bar.SetWidth(80)
// sets the width of the progress bar, but if terminal size smaller will be ignored
bar.SetMaxWidth(80)
// convert output to readable format (like KB, MB)
bar.SetUnits(pb.U_BYTES)
// and start
bar.Start()
```
## Progress bar for IO Operations
```go
// create and start bar
bar := pb.New(myDataLen).SetUnits(pb.U_BYTES)
bar.Start()
// my io.Reader
r := myReader
// my io.Writer
w := myWriter
// create proxy reader
reader := bar.NewProxyReader(r)
// and copy from pb reader
io.Copy(w, reader)
```
```go
// create and start bar
bar := pb.New(myDataLen).SetUnits(pb.U_BYTES)
bar.Start()
// my io.Reader
r := myReader
// my io.Writer
w := myWriter
// create multi writer
writer := io.MultiWriter(w, bar)
// and copy
io.Copy(writer, r)
bar.Finish()
```
## Custom Progress Bar Look-and-feel
```go
bar.Format("<.- >")
```
## Multiple Progress Bars (experimental and unstable)
Do not print to terminal while pool is active.
```go
package main
import (
"math/rand"
"sync"
"time"
"gopkg.in/cheggaaa/pb.v1"
)
func main() {
// create bars
first := pb.New(200).Prefix("First ")
second := pb.New(200).Prefix("Second ")
third := pb.New(200).Prefix("Third ")
// start pool
pool, err := pb.StartPool(first, second, third)
if err != nil {
panic(err)
}
// update bars
wg := new(sync.WaitGroup)
for _, bar := range []*pb.ProgressBar{first, second, third} {
wg.Add(1)
go func(cb *pb.ProgressBar) {
for n := 0; n < 200; n++ {
cb.Increment()
time.Sleep(time.Millisecond * time.Duration(rand.Intn(100)))
}
cb.Finish()
wg.Done()
}(bar)
}
wg.Wait()
// close pool
pool.Stop()
}
```
The result will be as follows:
```
$ go run example/multiple.go
First 34 / 200 [=========>---------------------------------------------] 17.00% 00m08s
Second 42 / 200 [===========>------------------------------------------] 21.00% 00m06s
Third 36 / 200 [=========>---------------------------------------------] 18.00% 00m08s
```