https://github.com/fortio/progressbar
Zero dependency golang progress bar for terminal/CLIs
https://github.com/fortio/progressbar
examples golang-library progress-bar progressbar tui zero-dependency
Last synced: 4 months ago
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Zero dependency golang progress bar for terminal/CLIs
- Host: GitHub
- URL: https://github.com/fortio/progressbar
- Owner: fortio
- License: apache-2.0
- Created: 2025-03-06T21:47:56.000Z (7 months ago)
- Default Branch: main
- Last Pushed: 2025-04-18T22:59:58.000Z (6 months ago)
- Last Synced: 2025-05-02T09:12:36.950Z (5 months ago)
- Topics: examples, golang-library, progress-bar, progressbar, tui, zero-dependency
- Language: Go
- Homepage:
- Size: 288 KB
- Stars: 17
- Watchers: 3
- Forks: 0
- Open Issues: 1
-
Metadata Files:
- Readme: README.md
- License: LICENSE
Awesome Lists containing this project
README
# progressbar
[](https://pkg.go.dev/fortio.org/progressbar)
[](https://goreportcard.com/report/fortio.org/progressbar)
[](https://github.com/fortio/progressbar/actions/workflows/include.yml)
[](https://github.com/fortio/progressbar/releases/)
Zero dependency cross platform (just needs basic ANSI codes and Unicode font support,
and ANSI codes can be disabled too if needed) golang concurrent safe progress bar for terminal/CLIs, with 8x the resolution of others (8 steps per character).
Shows a spinner and/or a progress bar with optional prefix and extra info.
Also provides reader/writer wrappers to automatically show progress of downloads/uploads
or other io operations, as well as a Writer that can be used concurrently with the progress bar to show other output on screen.
## Examples
See [examples/](examples/)
### Manually updating a progress bar and additional output
Manually handling a 2-line output update (1 misc line and the 1 line for the progress bar):
```go
pb := progressbar.NewBar()
fmt.Print("Progress bar example\n\n") // 1 empty line before the progress bar, for the demo
n := 1000
for i := 0; i <= n; i++ {
pb.ProgressBar(100. * float64(i) / float64(n))
if i%63 == 0 {
progressbar.MoveCursorUp(1)
fmt.Printf("Just an extra demo print for %d\n", i)
}
time.Sleep(20 * time.Millisecond)
}
```
Source: [examples/simple/simple.go](examples/simple/example.go) (`-moveup` mode)
### Concurrent safe screen writer example
```go
pb := progressbar.NewBar()
w := pb.Writer()
fmt.Fprintln(w, "Progress bar example")
// demonstrate concurrency safety:
go PrintStuff(w, *everyFlag)
// exact number of 'pixels', just to demo every smooth step:
n := pb.Width * 8
for i := 0; i <= n; i++ {
pb.ProgressBar(100. * float64(i) / float64(n))
time.Sleep(*delayFlag)
}
```
```sh
go run fortio.org/progressbar/examples/simple@latest -color
```
Produces
Or without color:
```
◅███████████████████████████▊ ▻ 69.4%
```
Source: [examples/simple/example.go](examples/simple/example.go) (default mode)
### Automatic Reader or Writer progress bar
```go
reader := progressbar.NewAutoReader(progressbar.NewBar(), resp.Body, resp.ContentLength)
_, err = io.Copy(os.Stdout, reader)
reader.Close()
```
See it in action with a progress bar while downloading a URL:
```sh
go run fortio.org/progressbar/examples/auto@latest https://go.dev/ > go_dev.html
```
Will show a progress bar for instance
```
$ go run ./examples/auto https://go.dev/dl/go1.24.1.src.tar.gz > /dev/null
Fetching https://go.dev/dl/go1.24.1.src.tar.gz
⣾ █████████████████████▌ 53.7% 15.766 Mb out of 29.352 Mb, 293ms elapsed, 53.790 Mb/s, 253ms remaining
```
Source (now includes a multi bar separating R/W): [auto_examples/auto/auto_example.go](auto_examples/auto/auto_example.go)
### Multiple Bars updating concurrently
```go
cfg := progressbar.DefaultConfig()
cfg.ExtraLines = 1
cfg.ScreenWriter = os.Stdout
mbar := cfg.NewMultiBarPrefixes(
"b1",
"longest prefix",
"short",
"b4",
)
wg := sync.WaitGroup{}
for i, bar := range mbar {
wg.Add(1)
// Update at random speed so bars move differently for a demo:
delay := time.Duration(5+rand.IntN(40)) * time.Millisecond
bar.WriteAbove(fmt.Sprintf("\t\t\tBar %d delay is %v", i+1, delay))
go func(b *progressbar.State) {
UpdateBar(b, delay)
wg.Done()
}(bar)
}
wg.Wait()
progressbar.MultiBarEnd(mbar)
```
Complete source: [multi_example/multi_example.go](multi_example/multi_example.go)
Which includes adding extra bars dynamically.
### Multicurl
You can see it in use in [fortio/multicurl](https://github.com/fortio/multicurl?tab=readme-ov-file#multicurl) cli too.
## See also
If you have more advanced needs for TUI including raw mode input or readline, you can also see/use/have a look at
[github.com/fortio/terminal](https://github.com/fortio/terminal#terminal)
And still use this for a progress bar part.
It is used for instance in [github.com/fortio/fps's web mode progress update](https://github.com/fortio/fps#web-serving-fire-mode)
And [grol](https://github.com/grol-io/grol#grol)'s multi file processing progress info (`make grol-tests`)