func showProgress()

in example/ecr-pull/progress.go [42:158]
106 lines of code
22 McCabe index (conditional complexity)

func showProgress(ctx context.Context, ongoing *jobs, cs content.Store, out io.Writer) {
	var (
		ticker   = time.NewTicker(100 * time.Millisecond)
		fw       = progress.NewWriter(out)
		start    = time.Now()
		statuses = map[string]StatusInfo{}
		done     bool
	)
	defer ticker.Stop()

outer:
	for {
		select {
		case <-ticker.C:
			fw.Flush()

			tw := tabwriter.NewWriter(fw, 1, 8, 1, ' ', 0)

			resolved := "resolved"
			if !ongoing.isResolved() {
				resolved = "resolving"
			}
			statuses[ongoing.name] = StatusInfo{
				Ref:    ongoing.name,
				Status: resolved,
			}
			keys := []string{ongoing.name}

			activeSeen := map[string]struct{}{}
			if !done {
				active, err := cs.ListStatuses(ctx, "")
				if err != nil {
					log.G(ctx).WithError(err).Error("active check failed")
					continue
				}
				// update status of active entries!
				for _, active := range active {
					statuses[active.Ref] = StatusInfo{
						Ref:       active.Ref,
						Status:    "downloading",
						Offset:    active.Offset,
						Total:     active.Total,
						StartedAt: active.StartedAt,
						UpdatedAt: active.UpdatedAt,
					}
					activeSeen[active.Ref] = struct{}{}
				}
			}

			// now, update the items in jobs that are not in active
			for _, j := range ongoing.jobs() {
				key := remotes.MakeRefKey(ctx, j)
				keys = append(keys, key)
				if _, ok := activeSeen[key]; ok {
					continue
				}

				status, ok := statuses[key]
				if !done && (!ok || status.Status == "downloading") {
					info, err := cs.Info(ctx, j.Digest)
					if err != nil {
						if !errdefs.IsNotFound(err) {
							log.G(ctx).WithError(err).Errorf("failed to get content info")
							continue outer
						} else {
							statuses[key] = StatusInfo{
								Ref:    key,
								Status: "waiting",
							}
						}
					} else if info.CreatedAt.After(start) {
						statuses[key] = StatusInfo{
							Ref:       key,
							Status:    "done",
							Offset:    info.Size,
							Total:     info.Size,
							StartedAt: start,
							UpdatedAt: info.CreatedAt,
						}
					} else {
						statuses[key] = StatusInfo{
							Ref:    key,
							Status: "exists",
						}
					}
				} else if done {
					if ok {
						if status.Status != "done" && status.Status != "exists" {
							status.Status = "done"
							statuses[key] = status
						}
					} else {
						statuses[key] = StatusInfo{
							Ref:    key,
							Status: "done",
						}
					}
				}
			}

			var ordered []StatusInfo
			for _, key := range keys {
				ordered = append(ordered, statuses[key])
			}

			Display(tw, ordered, start)
			tw.Flush()

			if done {
				fw.Flush()
				return
			}
		case <-ctx.Done():
			done = true // allow ui to update once more
		}
	}
}