update container, add collect methods and main entrypoint

container.go

@@ -1,22 +1,77 @@
 package main
 
 import (
+	"fmt"
+	"math"
+
+	"github.com/fsouza/go-dockerclient"
 	ui "github.com/gizak/termui"
 )
 
-type Container struct {
+type Widgets struct {
 	cid    *ui.Par
 	cpu    *ui.Gauge
 	memory *ui.Gauge
 }
 
-func (c *Container) UpdateCPU(n int) {
-	c.cpu.BarColor = colorScale(n)
-	c.cpu.Percent = n
+func NewWidgets(id string) *Widgets {
+	cid := ui.NewPar(id)
+	cid.Border = false
+	cid.Height = 2
+	cid.Width = 10
+	cid.TextFgColor = ui.ColorWhite
+	return &Widgets{cid, mkGauge(), mkGauge()}
 }
 
-func (c *Container) UpdateMem(n int) {
-	c.memory.Percent = n
+type Container struct {
+	id      string
+	widgets *Widgets
+	stats   chan *docker.Stats
+	done    chan bool
+}
+
+func NewContainer(cid string) *Container {
+	return &Container{
+		id:      cid,
+		widgets: NewWidgets(cid),
+		stats:   make(chan *docker.Stats),
+		done:    make(chan bool),
+	}
+}
+
+func (c *Container) Collect(client *docker.Client) {
+
+	go func() {
+		fmt.Sprintf("starting collector for container: %s\n", c.id)
+		opts := docker.StatsOptions{
+			ID:     c.id,
+			Stats:  c.stats,
+			Stream: true,
+			Done:   c.done,
+		}
+		client.Stats(opts)
+		fmt.Sprintf("stopping collector for container: %s\n", c.id)
+	}()
+
+	go func() {
+		for s := range c.stats {
+			c.UpdateMem(s.MemoryStats.Usage, s.MemoryStats.Limit)
+		}
+	}()
+
+}
+
+func (c *Container) UpdateCPU(n int) {
+	c.widgets.cpu.BarColor = colorScale(n)
+	c.widgets.cpu.Percent = n
+}
+
+func (c *Container) UpdateMem(cur uint64, limit uint64) {
+	c.widgets.memory.Percent = round((float64(cur) / float64(limit)) * 100)
+}
+
+func round(num float64) int {
+	return int(num + math.Copysign(0.5, num))
 }
 
 func colorScale(n int) ui.Attribute {

grid.go

@@ -11,12 +11,7 @@ type Grid struct {
 }
 
 func (g *Grid) AddContainer(id string) {
-	cid := ui.NewPar(id)
-	cid.Border = false
-	cid.Height = 2
-	cid.Width = 10
-	cid.TextFgColor = ui.ColorWhite
-	g.containers[id] = &Container{cid, mkGauge(), mkGauge()}
+	g.containers[id] = NewContainer(id)
 }
 
 // Return sorted list of active container IDs
@@ -33,9 +28,9 @@ func (g *Grid) Rows() (rows []*ui.Row) {
 	for _, cid := range g.CIDs() {
 		c := g.containers[cid]
 		rows = append(rows, ui.NewRow(
-			ui.NewCol(1, 0, c.cid),
-			ui.NewCol(2, 0, c.cpu),
-			ui.NewCol(2, 0, c.memory),
+			ui.NewCol(1, 0, c.widgets.cid),
+			ui.NewCol(2, 0, c.widgets.cpu),
+			ui.NewCol(2, 0, c.widgets.memory),
 		))
 	}
 	return rows
@@ -87,25 +82,14 @@ func header() *ui.Row {
 	)
 }
 
-func NewGrid() {
+func Display(g *Grid) {
 	if err := ui.Init(); err != nil {
 		panic(err)
 	}
 	defer ui.Close()
 
-	g := &Grid{make(map[string]*Container)}
-	for _, id := range []string{" 12345", " 56789", " 00001"} {
-		g.AddContainer(id)
-	}
-
-	par := ui.NewPar("<> This row has 3 columns\n<- Widgets can be stacked up like left side\n<- Stacked widgets are treated as a single widget")
-	par.Height = 5
-	par.BorderLabel = "Demonstration"
-
 	// build layout
-	ui.Body.AddRows(
-		header(),
-	)
+	ui.Body.AddRows(header())
 
 	for _, row := range g.Rows() {
 		ui.Body.AddRows(row)
@@ -120,17 +104,12 @@ func NewGrid() {
 		ui.StopLoop()
 	})
 	ui.Handle("/timer/1s", func(e ui.Event) {
-		t := e.Data.(ui.EvtTimer)
-		i := t.Count
-		if i > 103 {
-			ui.StopLoop()
-			return
-		}
-
-		for _, c := range g.containers {
-			c.UpdateCPU((c.cpu.Percent + 5) % 100)
-			c.UpdateMem((c.memory.Percent + 12) % 100)
-		}
+		//		t := e.Data.(ui.EvtTimer)
+		//		i := t.Count
+		//		if i > 103 {
+		//			ui.StopLoop()
+		//			return
+		//		}
 
 		ui.Render(ui.Body)
 	})
@@ -144,7 +123,3 @@ func NewGrid() {
 
 	ui.Loop()
 }
-
-func main() {
-	NewGrid()
-}

main.go

@@ -0,0 +1,30 @@
+package main
+
+import (
+	"fmt"
+	"os"
+
+	"github.com/fsouza/go-dockerclient"
+)
+
+func main() {
+	if len(os.Args) < 2 {
+		fmt.Println("no container provided")
+		os.Exit(1)
+	}
+
+	client, err := docker.NewClient("tcp://127.0.0.1:4243")
+	if err != nil {
+		panic(err)
+	}
+
+	g := &Grid{make(map[string]*Container)}
+	g.AddContainer(os.Args[1])
+
+	for _, c := range g.containers {
+		c.Collect(client)
+	}
+
+	Display(g)
+
+}