basic power widget

i3status/power.go

@@ -0,0 +1,54 @@
+package i3status
+
+import (
+	"bytes"
+	"fmt"
+	"os/exec"
+	"strconv"
+	"time"
+)
+
+const (
+	Charging    = "charging"
+	Discharging = "discharging"
+	Charged     = "charged"
+)
+
+type PowerWidget struct {
+	BaseWidget
+}
+
+func NewPowerWidget() *PowerWidget {
+	instanceCount++
+	w := PowerWidget{
+		BaseWidget: *NewBaseWidget(),
+	}
+	return &w
+}
+
+func (w *PowerWidget) execCommand() string {
+	var out bytes.Buffer
+	cmd := exec.Command("acpi", "-b")
+	cmd.Stdout = &out
+	cmd.Run()
+	str, _ := out.ReadString('\n')
+	return str
+}
+
+func (w *PowerWidget) basicLoop() {
+	msg := NewMessage()
+	msg.Name = "Power"
+	msg.Color = "#ffffff"
+	msg.Instance = strconv.Itoa(w.Instance)
+	for {
+		str := w.execCommand()
+		msg.FullText = fmt.Sprintf("%s", str)
+		w.Output <- *msg
+		time.Sleep(5000 * time.Millisecond)
+	}
+}
+
+func (w *PowerWidget) Start() {
+	go w.basicLoop()
+	go w.readLoop()
+}

main.go

@@ -27,8 +27,9 @@ func main() {
 	fmt.Println("[")
 	b := i3status.NewBar()
 
-	b.Add(i3status.NewTimerWidget())
 	//b.Add(i3status.NewDateWidget())
+	b.Add(i3status.NewTimerWidget())
+	b.Add(i3status.NewPowerWidget())
 	b.Add(i3status.NewOnOffWidget())
 	b.Add(i3status.NewI3statusWidget())
 	b.Add(i3status.NewEchoWidget())

test/power_test.go

@@ -0,0 +1,37 @@
+package i3status_test
+
+import (
+	"github.com/ghedamat/go-i3status/i3status"
+	. "github.com/smartystreets/goconvey/convey"
+	"testing"
+)
+
+func TestPowerWidgetConstructor(t *testing.T) {
+	Convey("Given two channels", t, func() {
+		c := make(chan i3status.Message)
+		i := make(chan i3status.Entry)
+		Convey("When power is created", func() {
+			w := i3status.NewPowerWidget()
+			w.SetChannels(c, i)
+			Convey("output channel is available", func() {
+				So(w.Output, ShouldEqual, c)
+			})
+		})
+	})
+}
+
+func TestPowerWidgetHasMessage(t *testing.T) {
+	Convey("Given a widget", t, func() {
+		c := make(chan i3status.Message)
+		i := make(chan i3status.Entry)
+		w := i3status.NewPowerWidget()
+		w.SetChannels(c, i)
+		Convey("When power is started", func() {
+			w.Start()
+			Convey("output message is available", func() {
+				msg := <-c
+				So(msg.FullText, ShouldContainSubstring, "Battery")
+			})
+		})
+	})
+}