Add a widget to display the log file in reverse order

logging/log.go

@@ -0,0 +1,110 @@
+package logging
+
+import (
+	"fmt"
+	//"io/ioutil"
+	"log"
+	"os"
+	"path/filepath"
+	"strings"
+
+	"github.com/senorprogrammer/wtf/wtf"
+)
+
+const maxBufferSize int64 = 1024
+
+type Widget struct {
+	wtf.TextWidget
+
+	filePath string
+}
+
+func NewWidget() *Widget {
+	widget := Widget{
+		TextWidget: wtf.NewTextWidget(" Logs ", "logging", true),
+
+		filePath: logFilePath(),
+	}
+
+	return &widget
+}
+
+/* -------------------- Exported Functions -------------------- */
+
+func Log(msg string) {
+	if logFileMissing() {
+		return
+	}
+
+	f, err := os.OpenFile(logFilePath(), os.O_RDWR|os.O_CREATE|os.O_APPEND, 0666)
+	if err != nil {
+		log.Fatalf("error opening file: %v", err)
+	}
+	defer f.Close()
+
+	log.SetOutput(f)
+	log.Println(msg)
+}
+
+func (widget *Widget) Refresh() {
+	if logFileMissing() {
+		return
+	}
+
+	widget.UpdateRefreshedAt()
+	widget.View.SetTitle(fmt.Sprintf("%s", widget.Name))
+
+	widget.View.SetText(fmt.Sprintf("%s", widget.tailFile()))
+}
+
+/* -------------------- Unexported Functions -------------------- */
+
+func logFileMissing() bool {
+	return logFilePath() == ""
+}
+
+func logFilePath() string {
+	dir, err := wtf.Home()
+	if err != nil {
+		return ""
+	}
+
+	return filepath.Join(dir, ".wtf", "log.txt")
+}
+
+func (widget *Widget) tailFile() string {
+	file, err := os.Open(widget.filePath)
+	if err != nil {
+		return ""
+	}
+	defer file.Close()
+
+	stat, err := file.Stat()
+	if err != nil {
+		return ""
+	}
+
+	bufferSize := maxBufferSize
+	if maxBufferSize > stat.Size() {
+		bufferSize = stat.Size()
+	}
+
+	startPos := stat.Size() - bufferSize
+
+	buff := make([]byte, bufferSize)
+	_, err = file.ReadAt(buff, startPos)
+	if err != nil {
+		return ""
+	}
+
+	dataArr := strings.Split(string(buff), "\n")
+
+	// Reverse the array of lines
+	// Offset by two to account for the blank line at the end
+	last := len(dataArr) - 2
+	for i := 0; i < len(dataArr)/2; i++ {
+		dataArr[i], dataArr[last-i] = dataArr[last-i], dataArr[i]
+	}
+
+	return fmt.Sprintf("%s\n", strings.Join(dataArr, "\n"))
+}

wtf.go

@@ -29,6 +29,7 @@ import (
 	"github.com/senorprogrammer/wtf/ipaddresses/ipinfo"
 	"github.com/senorprogrammer/wtf/jenkins"
 	"github.com/senorprogrammer/wtf/jira"
+	"github.com/senorprogrammer/wtf/logging"
 	"github.com/senorprogrammer/wtf/newrelic"
 	"github.com/senorprogrammer/wtf/opsgenie"
 	"github.com/senorprogrammer/wtf/power"
@@ -221,6 +222,8 @@ func addWidget(app *tview.Application, pages *tview.Pages, widgetName string) {
 		Widgets = append(Widgets, jenkins.NewWidget())
 	case "jira":
 		Widgets = append(Widgets, jira.NewWidget())
+	case "logging":
+		Widgets = append(Widgets, logging.NewWidget())
 	case "newrelic":
 		Widgets = append(Widgets, newrelic.NewWidget())
 	case "opsgenie":
@@ -285,10 +288,10 @@ func main() {
 	go redrawApp(app)
 	go watchForConfigChanges(app, flags.Config, display.Grid, pages)
 
+	logging.Log("Running!")
+
 	if err := app.SetRoot(pages, true).Run(); err != nil {
 		fmt.Printf("Error: %v\n", err)
 		os.Exit(1)
 	}
-
-	wtf.Log("Running!")
 }

wtf/log.go

@@ -1,26 +0,0 @@
-package wtf
-
-import (
-	"log"
-	"os"
-	"path/filepath"
-)
-
-//Log basic message logging, defaults to ~/.wtf/log.txt
-func Log(message string) {
-
-	dir, err := Home()
-	if err != nil {
-		return
-	}
-
-	logfile := filepath.Join(dir, ".wtf", "log.txt")
-	f, err := os.OpenFile(logfile, os.O_RDWR|os.O_CREATE|os.O_APPEND, 0666)
-	if err != nil {
-		log.Fatalf("error opening file: %v", err)
-	}
-	defer f.Close()
-
-	log.SetOutput(f)
-	log.Println(message)
-}