Initial import of service-monitor

.gitignore

@@ -14,3 +14,4 @@
 .glide/
 
 service-generator/service-generator
+service-monitor/service-monitor

service-monitor/logscmd.go

@@ -0,0 +1,198 @@
+package main
+
+import (
+	"bytes"
+	"fmt"
+	"io/ioutil"
+	"strings"
+	"time"
+
+	"github.com/coreos/go-systemd/sdjournal"
+	"github.com/gdamore/tcell"
+	"github.com/rivo/tview"
+	"github.com/spf13/cobra"
+)
+
+type LogModel struct {
+	Name        string
+	Description string
+	Matches     []sdjournal.Match
+}
+
+var (
+	logsCmd = &cobra.Command{
+		Use:   "logs",
+		Short: "monitor service logs",
+		Long:  `The logs command starts an interactive service monitor`,
+		RunE: func(cmd *cobra.Command, args []string) error {
+			ts, err := services()
+			if err != nil {
+				return fmt.Errorf("Can't find systemd services: %s", err)
+			}
+
+			model := []LogModel{
+				{
+					Name:        "All",
+					Description: "Everything in the log",
+					Matches:     []sdjournal.Match{},
+				},
+				{
+					Name:        "All Errors",
+					Description: "All errors in the log",
+					Matches: []sdjournal.Match{
+						{
+							Field: sdjournal.SD_JOURNAL_FIELD_PRIORITY,
+							Value: "3",
+						},
+					},
+				},
+				{
+					Name:        "All Warnigns",
+					Description: "All warnings in the log",
+					Matches: []sdjournal.Match{
+						{
+							Field: sdjournal.SD_JOURNAL_FIELD_PRIORITY,
+							Value: "3",
+						},
+						{
+							Field: sdjournal.SD_JOURNAL_FIELD_PRIORITY,
+							Value: "4",
+						},
+					},
+				},
+			}
+			for _, service := range ts {
+				model = append(model, LogModel{
+					Name:        service.Name,
+					Description: service.Description,
+					Matches: []sdjournal.Match{
+						{
+							Field: sdjournal.SD_JOURNAL_FIELD_SYSTEMD_UNIT,
+							Value: service.Name,
+						},
+					},
+				})
+			}
+
+			var apperr error
+			app := tview.NewApplication()
+
+			list := tview.NewList()
+			list.
+				SetBorder(true).
+				SetTitle("Logs")
+
+			textView := tview.NewTextView()
+			textView.
+				SetDynamicColors(true).
+				SetScrollable(true).
+				SetChangedFunc(func() {
+					app.Draw()
+				}).
+				SetDoneFunc(func(key tcell.Key) {
+					app.SetFocus(list)
+				})
+			textView.
+				SetBorder(true).
+				SetTitle("Service Log")
+
+			list.SetDoneFunc(func() {
+				app.SetFocus(textView)
+			})
+
+			errLogView := tview.NewTextView()
+			errLogView.
+				SetDynamicColors(true).
+				SetScrollable(true).
+				SetChangedFunc(func() {
+					app.Draw()
+				}).
+				SetDoneFunc(func(key tcell.Key) {
+					app.SetFocus(list)
+				})
+			errLogView.
+				SetBorder(true).
+				SetTitle("Global Error Log")
+
+			r := readLog([]sdjournal.Match{})
+			errReader := readLog([]sdjournal.Match{
+				{
+					Field: sdjournal.SD_JOURNAL_FIELD_PRIORITY,
+					Value: "3",
+				},
+			})
+
+			go func() {
+				buf, _ := ioutil.ReadAll(errReader)
+				errLogView.SetText(string(buf))
+				errLogView.ScrollToEnd()
+				for {
+					line, err := errReader.ReadString('\n')
+					if err != nil {
+						return
+					}
+					errLogView.SetText(strings.TrimSpace(line))
+					errLogView.ScrollToEnd()
+				}
+			}()
+
+			list.SetSelectedFunc(func(index int, primText, secText string, shortcut rune) {
+				u := model[index]
+				textView.Clear()
+				textView.SetTitle(u.Name)
+				r = readLog(u.Matches)
+				buf, _ := ioutil.ReadAll(r)
+				textView.SetText(string(buf))
+				textView.ScrollToEnd()
+				app.SetFocus(textView)
+			})
+
+			for _, srv := range model {
+				list.AddItem(srv.Name, srv.Description, 0, nil)
+			}
+
+			flex := tview.NewFlex().
+				AddItem(list, 32, 1, true).
+				AddItem(tview.NewFlex().SetDirection(tview.FlexRow).
+					AddItem(textView, 0, 8, false).
+					AddItem(errLogView, 8, 1, false), 0, 1, false)
+
+			if err := app.SetRoot(flex, true).Run(); err != nil {
+				return err
+			}
+			return apperr
+		},
+	}
+)
+
+func readLog(matches []sdjournal.Match) *bytes.Buffer {
+	r, err := sdjournal.NewJournalReader(sdjournal.JournalReaderConfig{
+		Since:   time.Duration(-60) * time.Minute * 24,
+		Matches: matches,
+	})
+
+	if err != nil {
+		panic(err)
+	}
+	if r == nil {
+		panic("journal reader is nil")
+	}
+
+	defer r.Close()
+	// r.Rewind()
+
+	b := []byte{}
+	buf := bytes.NewBuffer(b)
+
+	// and follow the reader synchronously
+	timeout := time.Duration(1) * time.Second
+	if err = r.Follow(time.After(timeout), buf); err != sdjournal.ErrExpired {
+		panic(err)
+	}
+
+	return buf
+}
+
+func init() {
+	RootCmd.AddCommand(logsCmd)
+}

service-monitor/main.go

@@ -0,0 +1,23 @@
+package main
+
+import (
+	"os"
+
+	"github.com/spf13/cobra"
+)
+
+var (
+	RootCmd = &cobra.Command{
+		Use:           "service-monitor",
+		Short:         "service-monitor monitors systemd Units",
+		Long:          "service-monitor is a convenient little tool to monitor systemd Units",
+		SilenceErrors: false,
+		SilenceUsage:  true,
+	}
+)
+
+func main() {
+	if err := RootCmd.Execute(); err != nil {
+		os.Exit(-1)
+	}
+}

service-monitor/services.go

@@ -0,0 +1,49 @@
+package main
+
+import (
+	"strings"
+
+	"github.com/coreos/go-systemd/dbus"
+)
+
+type Services []dbus.UnitStatus
+
+func services() (Services, error) {
+	res := []dbus.UnitStatus{}
+	conn, err := dbus.New()
+	if err != nil {
+		return res, err
+	}
+	us, err := conn.ListUnits()
+	if err != nil {
+		return res, err
+	}
+	for _, v := range us {
+		if !strings.HasSuffix(v.Name, ".service") {
+			continue
+		}
+
+		res = append(res, v)
+	}
+
+	return res, nil
+}
+
+func (ts Services) Contains(name string) bool {
+	for _, t := range ts {
+		if t.Name == name {
+			return true
+		}
+	}
+
+	return false
+}
+
+func (ts Services) Strings() []string {
+	var res []string
+	for _, t := range ts {
+		res = append(res, t.Name)
+	}
+
+	return res
+}