make progress bar POC for pause

packer/progressbar.go

@@ -5,7 +5,9 @@ package packer
 import (
 	"io"
 	"path/filepath"
+	"strings"
 	"sync"
+	"time"
 
 	pb "github.com/cheggaaa/pb"
 )
@@ -25,11 +27,66 @@ type UiProgressBar struct {
 
 func (p *UiProgressBar) TrackProgress(src string, currentSize, totalSize int64, stream io.ReadCloser) io.ReadCloser {
 	if p == nil {
+
 		return stream
 	}
 	p.lock.Lock()
 	defer p.lock.Unlock()
+	// custom prefix used to track configured waits rather than file downloads
+	// TODO: next time we feel we can justify a breaking interface change, this
+	// deserves its own method on the progress bar rather than this hacked
+	// workaround.
+	if strings.Contains(src, "-packerwaiter-") {
+		realPrefix := strings.Replace(src, "-packerwaiter-", "", -1)
+		return p.TrackProgressWait(realPrefix, currentSize, totalSize, stream)
+	}
+	return p.TrackProgressFile(src, currentSize, totalSize, stream)
 
+}
+
+func (p *UiProgressBar) TrackProgressWait(src string, currentSize, totalSize int64, stream io.ReadCloser) io.ReadCloser {
+	newPb := pb.New64(totalSize)
+	newPb.SetUnits(pb.U_DURATION)
+	newPb.ShowPercent = false
+	newPb.Prefix(src)
+
+	if p.pool == nil {
+
+		pool := pb.NewPool()
+		err := pool.Start()
+		if err != nil {
+			// here, we probably cannot lock
+			// stdout, so let's just return
+			// stream to avoid any error.
+			return stream
+		}
+		p.pool = pool
+	}
+	p.pool.Add(newPb)
+
+	p.pbs++
+	return &readCloser{
+		Reader: nil,
+		close: func() error {
+
+			for i := currentSize; i < totalSize; i++ {
+				newPb.Increment()
+				time.Sleep(time.Second)
+			}
+			newPb.Finish()
+			p.lock.Lock()
+			defer p.lock.Unlock()
+			p.pbs--
+			if p.pbs <= 0 {
+				p.pool.Stop()
+				p.pool = nil
+			}
+			return nil
+		},
+	}
+}
+
+func (p *UiProgressBar) TrackProgressFile(src string, currentSize, totalSize int64, stream io.ReadCloser) io.ReadCloser {
 	newPb := pb.New64(totalSize)
 	newPb.Set64(currentSize)
 	ProgressBarConfig(newPb, filepath.Base(src))

packer/provisioner.go

@@ -167,34 +167,10 @@ func (p *PausedProvisioner) Provision(ctx context.Context, ui packersdk.Ui, comm
 }
 
 func (p *PausedProvisioner) updatesWhilePausing(ctx context.Context, ui packersdk.Ui) error {
-	updateTime := 1
-	timeTicker := time.NewTicker(time.Duration(updateTime) * time.Second)
 	TotalTime := int64(math.Round(p.PauseBefore.Seconds()))
 	ElapsedTime := int64(0)
-	tickerChannel := make(chan bool)
+	pbCloser := ui.TrackProgress("-packerwaiter-Pausing...", ElapsedTime, TotalTime, ioutil.NopCloser(nil))
-	var err error
+	pbCloser.Close() // this is blocking
-	go func() {
-		for {
-			select {
-			case <-timeTicker.C:
-				ElapsedTime += int64(updateTime)
-				ui.TrackProgress("Pausing...", ElapsedTime, TotalTime, ioutil.NopCloser(nil))
-				// ui.Say(fmt.Sprintf("%v seconds left until the next provisioner", TotalTime))
-			case <-ctx.Done():
-				err = ctx.Err()
-				return
-			case <-tickerChannel:
-				return
-			}
-		}
-	}()
-	time.Sleep(p.PauseBefore)
-	timeTicker.Stop()
-	if err != nil {
-		return err
-	}
-	tickerChannel <- true
-
 	return nil
 }