Improve logs (introduce a progress-bar for tty devices)

[brandonkal]

Running the Go example, earth floods the terminal with lines like this:

+base | sha256:61b11419476186415e86da00c53c938fd32dc5904a889e1c3d40e238d69d168e 11%
+base | sha256:61b11419476186415e86da00c53c938fd32dc5904a889e1c3d40e238d69d168e 11%
+base | sha256:61b11419476186415e86da00c53c938fd32dc5904a889e1c3d40e238d69d168e 12%
+base | sha256:61b11419476186415e86da00c53c938fd32dc5904a889e1c3d40e238d69d168e 12%
+base | sha256:61b11419476186415e86da00c53c938fd32dc5904a889e1c3d40e238d69d168e 12%
+base | sha256:61b11419476186415e86da00c53c938fd32dc5904a889e1c3d40e238d69d168e 12%
+base | sha256:61b11419476186415e86da00c53c938fd32dc5904a889e1c3d40e238d69d168e 12%
+base | sha256:61b11419476186415e86da00c53c938fd32dc5904a889e1c3d40e238d69d168e 12%

Though it is a lot more of that than I've included here. I would expect this as a progress bar replacing the line on update rather than drawing a new line.

go build is silent on success so this is a lot messier.

[vladaionescu]

Makes sense, Brandon. We need to improve this.

(I believe those specific lines are from the progress of pulling some docker image - this can be made less verbose.)

[brandonkal]

Yes that is from pulling the image. My internet connection is slow so I get a higher amount of those lines.
With a tty, a simple wget-like progress bar would be better.
Without a tty, one solution is to filter out duplicate lines (that at least reduces it down to 100 lines for each pull).

[alexcb]

#143 changes the behaviour to only print out the progress every 5 seconds.

I agree that a tty progress bar would be nice to implement one day, so maybe we should leave this issue open?

[Gituser143]

Hey @vladaionescu! Can I work on this issue?

[vladaionescu]

Sounds good @Gituser143. This is where progress is printed BTW: https://github.com/earthly/earthly/blob/master/builder/solver_monitor.go#L178. Keep in mind that there may be multiple progress bars ongoing at a time and that the printing itself is being worked on in parallel: #338.

CC @MadhavJivrajani

[Gituser143]

Thank you @vladaionescu! I'll get to it...

[Gituser143]

@vladaionescu I've implemented a simple progress bar. It's declared here and values are updated like this. Let me know if I can open a PR so that you can see the changes and tell me what changes I'll have to make.

My overall implementation looks kind of like this:

var on sync.Once
progressBar := pb.New(100)
for _, vs := range ss.Statuses {
  .
  .
  .  
  progress := int(0)
  if vs.Total != 0 {
    progress = int(100.0 * float32(vs.Current) / float32(vs.Total))
  }
  if vs.Completed != nil {
    progress = 100
  }
  if vm.shouldPrintProgress(progress) {
    .
    .
    .
    on.Do(func() {
      vm.console.Printf("%s\n", vs.ID)
      progressBar.Start()
    })
    progressBar.SetCurrent(int64(progress))
  }
}
progressBar.Finish()

[vladaionescu]

It's a good start, however you probably need a separate progress bar for each of the items in ss.Statuses. These are multiple activities taking place in parallel and the relevant progress bars need to be updated in parallel. Feel free to open a PR even if it's WIP.

[vladaionescu]

This has been implemented and will be in the next release.