CLI progress indicator, initial import

Signed-off-by: Jan Broer <janeczku@yahoo.de>

libmachine/host.go

@@ -109,6 +109,8 @@ func ValidateHostName(name string) bool {
 
 func (h *Host) Create(name string) error {
 	// create the instance
+	log.Progress.Start("Creating the instance")
+	defer log.Progress.Stop()
 	if err := h.Driver.Create(); err != nil {
 		return err
 	}
@@ -120,6 +122,7 @@ func (h *Host) Create(name string) error {
 
 	// TODO: Not really a fan of just checking "none" here.
 	if h.Driver.DriverName() != "none" {
+		log.Progress.Start("Waiting for instance to come up")
 		if err := WaitForSSH(h); err != nil {
 			return err
 		}
@@ -129,6 +132,7 @@ func (h *Host) Create(name string) error {
 			return err
 		}
 
+		log.Progress.Start("Provisioning the instance")
 		if err := provisioner.Provision(*h.HostOptions.SwarmOptions, *h.HostOptions.AuthOptions, *h.HostOptions.EngineOptions); err != nil {
 			return err
 		}
@@ -252,6 +256,8 @@ func (h *Host) Upgrade() error {
 }
 
 func (h *Host) Remove(force bool) error {
+	log.Progress.Start("Removing the instance")
+	defer log.Progress.Stop()
 	if err := h.Driver.Remove(); err != nil {
 		if !force {
 			return err

log/log.go

@@ -36,7 +36,8 @@ type Logger interface {
 }
 
 var (
-	l = TerminalLogger{}
+	l        = TerminalLogger{}
+	Progress = NewProgress()
 )
 
 // TODO: I think this is superflous and can be replaced by one check for if

log/progress.go

@@ -0,0 +1,142 @@
+package log
+
+import (
+	"os"
+	"strings"
+	"time"
+
+	"github.com/docker/docker/pkg/term"
+)
+
+type Progressor struct {
+	title       string
+	stopChan    chan bool
+	isActive    bool
+	isTerminal  bool
+	withColor   bool
+	termWidth   int
+	clearBuffer []byte
+}
+
+func NewProgress() *Progressor {
+	var (
+		isTerminal  = false
+		withColor   = false
+		termWidth   int
+		clearBuffer []byte
+	)
+	fd := os.Stdout.Fd()
+	isTerminal = term.IsTerminal(fd)
+	if isTerminal {
+		winsize, err := term.GetWinsize(fd)
+		if err != nil {
+			termWidth = 80
+		} else {
+			termWidth = int(winsize.Width)
+		}
+		if isColorTerminal() {
+			withColor = true
+		}
+		clearBuffer = make([]byte, termWidth)
+		for i := range clearBuffer {
+			copy(clearBuffer[i:], " ")
+		}
+		copy(clearBuffer[0:], "\r")
+	}
+	return &Progressor{
+		stopChan:    make(chan bool, 1),
+		isActive:    false,
+		isTerminal:  isTerminal,
+		withColor:   withColor,
+		termWidth:   termWidth,
+		clearBuffer: clearBuffer,
+	}
+}
+
+// invoke with: 'log.Progress.Start("some description")'
+func (p *Progressor) Start(msg string) {
+	if !p.isTerminal || isDebug() {
+		Info(msg)
+		return
+	}
+	// stop current progress
+	if p.isActive {
+		p.Stop()
+	}
+	p.title = msg
+	p.isActive = true
+	go p.writer()
+}
+
+// invoke with: 'log.Progress.Stop()'
+func (p *Progressor) Stop() {
+	if p.isActive {
+		p.stopChan <- true
+		p.isActive = false
+		// variant a - remove progress
+		os.Stdout.Write(p.clearBuffer)
+		os.Stdout.Write([]byte("\r"))
+		os.Stdout.Sync()
+		// variant b - keep progress and prefix with "+"
+		//os.Stdout.Write([]byte("\r+\n"))
+		//os.Stdout.Sync()
+	}
+}
+
+// write out progress in a loop
+func (p *Progressor) writer() {
+	for {
+		select {
+		case <-p.stopChan:
+			return
+		default:
+			var out string
+			charset := []string{"|", "/", "-", "\\"}
+			for i := 0; i < len(charset); i++ {
+				out = charset[i]
+				if p.withColor {
+					out = "\x1b[1;32m" + charset[i] + "\x1b[0m"
+				}
+				os.Stdout.Write([]byte("\r" + out + " " + p.title))
+				os.Stdout.Sync()
+				time.Sleep(time.Millisecond * 150)
+			}
+		}
+	}
+}
+
+func isColorTerminal() bool {
+	matches := []string{
+		"Eterm",
+		"ansi",
+		"color",
+		"console",
+		"cygwin",
+		"dtterm",
+		"eterm-color",
+		"gnome",
+		"konsole",
+		"kterm",
+		"linux",
+		"mach-color",
+		"mlterm",
+		"putty",
+		"rxvt",
+		"screen",
+		"vt100",
+		"xterm",
+	}
+	if os.Getenv("COLORTERM") != "" {
+		return true
+	}
+	term := os.Getenv("TERM")
+	if term == "dumb" {
+		return false
+	}
+	for _, name := range matches {
+		if strings.Contains(term, name) {
+			return true
+		}
+	}
+	return false
+}

log/terminal.go

@@ -12,12 +12,20 @@ type TerminalLogger struct {
 }
 
 func (t TerminalLogger) log(args ...interface{}) {
+	if Progress.isActive {
+		Progress.Stop()
+		defer Progress.Start(Progress.title)
+	}
 	fmt.Print(args...)
 	fmt.Print(t.fieldOut, "\n")
 	t.fieldOut = ""
 }
 
 func (t TerminalLogger) logf(fmtString string, args ...interface{}) {
+	if Progress.isActive {
+		Progress.Stop()
+		defer Progress.Start(Progress.title)
+	}
 	fmt.Printf(fmtString, args...)
 	fmt.Print(t.fieldOut, "\n")
 	t.fieldOut = ""