gopv

gopv is a go library that helps track the progress of long-running tasks. It gives information such as time elapsed, percentage completed, current rps, eta and lots more.

Installation

go get github.com/pavel-krush/gopv

Usage

// Initialize library and start reporting the progress
pv := gopv.New(total)
gopv.StartCtx(ctx) // or gopv.StartChan(ctx.Done())

// Execute long-running procedure
for i := 0; i < total; i++ {
    <-time.After(time.Millisecond * 100)
    pv.Add(1)
}

Stopping

Progress tracker can be stopped by cancelling the context which was passed to StartCtx() or by closing(orwriting to) the channel passed to StartChan.

Customizing

By default, gopv generates reports in the following format:

[2023-12-02 08:52:24] - working (29/360) done 8%, RPS 9.65, elapsed 3s, ETA 34s

You can customize it by giving format to TextReporter, or on initialization by specialized constructor NewTextWithLegend:

pv := gopv.NewTextWithLegend(498, "{progress_bar} {now} {percent_int} {rps_avg} ")

Which produces the following output:

[######################--------------------------------------------------------] 2023-12-03 01:45:00 3 8.99

Legend placeholders

There are many placeholders available for TextReporter:

{now} - current time
{started_at} - time when progress was started
{dt} - time since last report
{total} - total number of items
{done} - number of items done
{left} - number of items left
{ratio} - ratio of done items to total
{percent_int} - integer percent of done items to total
{percent_float} - percent of done items to total
{elapsed} - time elapsed since start
{eta} - estimated time to finish
{rps_avg} - average done items per second
{rps_inst} - instant RPS(rps since last report)
{rpm} - average done items per minute
{progress_bar} - text-based progress bar

Synchronizing

When controlling context is canceled or channel is closed, gopv will stop reporting progress. To guarantee that the last report is printed, you can use Done() method which returns a channel that is closed when the last report is printed:

fmt.Println("executing a long task")
ctx, cancel := context.WithCancel(context.Background())
pv := gopv.New(total)
pv.StartCtx(ctx)

// do the work

cancel()
<-pv.Done()
fmt.Println("done")

pavel-krush / gopv