system daemon with launchd

Author: creativeprojects

.gitignore

@@ -21,3 +21,6 @@
 
 # test output
 /coverage.out
+
+# log files
+/*.log

examples/dev.yaml

@@ -81,6 +81,7 @@ self:
         source: ./
         schedule:
         - "*:00,30"
+        schedule-permission: user
     check:
         schedule:
         - "*:15,45"

main.go

@@ -8,6 +8,7 @@ import (
 	"path/filepath"
 	"runtime"
 	"runtime/debug"
+	"syscall"
 	"text/tabwriter"
 	"time"
 
@@ -314,7 +315,7 @@ func runProfile(
 
 	// Catch CTR-C keypress
 	sigChan := make(chan os.Signal, 1)
-	signal.Notify(sigChan, os.Interrupt, os.Kill)
+	signal.Notify(sigChan, os.Interrupt, os.Kill, syscall.SIGTERM, syscall.SIGABRT)
 
 	wrapper := newResticWrapper(
 		resticBinary,

schedule/schedule.go

@@ -1,6 +1,10 @@
 package schedule
 
 import (
+	"os"
+	"runtime"
+
+	"github.com/creativeprojects/clog"
 	"github.com/creativeprojects/resticprofile/constants"
 )
 
@@ -81,3 +85,45 @@ func (j *Job) Status() error {
 	}
 	return nil
 }
+
+// getSchedulePermission returns the permission defined from the configuration,
+// or the best guess considering the current user permission.
+//
+// This method is for Unixes only
+func (j *Job) getSchedulePermission() string {
+	const message = "you have not specified the permission for your schedule (system or user): assuming "
+	if j.config.Permission() == constants.SchedulePermissionSystem ||
+		j.config.Permission() == constants.SchedulePermissionUser {
+		// well defined
+		return j.config.Permission()
+	}
+	// best guess is depending on the user being root or not:
+	if os.Geteuid() == 0 {
+		if runtime.GOOS != "darwin" {
+			// darwin can backup protected files without the need of a system task; no need to bother the user then
+			clog.Warning(message, "system")
+		}
+		return constants.SchedulePermissionSystem
+	}
+	if runtime.GOOS != "darwin" {
+		// darwin can backup protected files without the need of a system task; no need to bother the user then
+		clog.Warning(message, "user")
+	}
+	return constants.SchedulePermissionUser
+}
+
+// checkPermission returns true if the user is allowed.
+//
+// This method is for Unixes only
+func (j *Job) checkPermission(permission string) bool {
+	if permission == constants.SchedulePermissionUser {
+		// user mode is always available
+		return true
+	}
+	if os.Geteuid() == 0 {
+		// user has sudoed
+		return true
+	}
+	// last case is system (or undefined) + no sudo
+	return false
+}

schedule/schedule_darwin.go

@@ -11,7 +11,10 @@ import (
 	"os"
 	"os/exec"
 	"path"
+	"regexp"
+	"sort"
 	"strings"
+	"text/tabwriter"
 
 	"github.com/creativeprojects/resticprofile/calendar"
 	"github.com/creativeprojects/resticprofile/constants"
@@ -31,8 +34,9 @@ const (
 	GlobalAgentPath = "/Library/LaunchAgents"
 	GlobalDaemons   = "/Library/LaunchDaemons"
 
-	namePrefix     = "local.resticprofile"
-	agentExtension = ".agent.plist"
+	namePrefix      = "local.resticprofile"
+	agentExtension  = ".agent.plist"
+	daemonExtension = ".plist"
 
 	codeServiceNotFound = 113
 )
@@ -89,10 +93,37 @@ func Close() {
 
 // createJob creates a plist file and register it with launchd
 func (j *Job) createJob(schedules []*calendar.Event) error {
-	ok := j.checkPermission(j.config.Permission())
+	permission := j.getSchedulePermission()
+	ok := j.checkPermission(permission)
 	if !ok {
 		return errors.New("user is not allowed to create a system job: please restart resticprofile as root (with sudo)")
 	}
+	filename, err := j.createPlistFile(schedules)
+	if err != nil {
+		if filename != "" {
+			os.Remove(filename)
+		}
+		return err
+	}
+
+	j.fixFileOwner(filename)
+	if err != nil {
+		return err
+	}
+
+	// load the service
+	cmd := exec.Command(launchctlBin, commandLoad, filename)
+	cmd.Stdout = os.Stdout
+	cmd.Stderr = os.Stderr
+	err = cmd.Run()
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func (j *Job) createPlistFile(schedules []*calendar.Event) (string, error) {
 	name := getJobName(j.config.Title(), j.config.SubTitle())
 	job := &LaunchJob{
 		Label:                 name,
@@ -105,94 +136,110 @@ func (j *Job) createJob(schedules []*calendar.Event) error {
 		StartCalendarInterval: getCalendarIntervalsFromSchedules(schedules),
 	}
 
-	filename, err := getFilename(name, j.config.Permission())
+	filename, err := getFilename(name, j.getSchedulePermission())
 	if err != nil {
-		return err
+		return "", err
 	}
 	file, err := os.Create(filename)
 	if err != nil {
-		return err
+		return "", err
 	}
 	defer file.Close()
 
 	encoder := plist.NewEncoder(file)
 	encoder.Indent("\t")
 	err = encoder.Encode(job)
 	if err != nil {
-		return err
+		return filename, err
 	}
+	return filename, nil
+}
 
-	// load the service
-	cmd := exec.Command(launchctlBin, commandLoad, filename)
-	cmd.Stdout = os.Stdout
-	cmd.Stderr = os.Stderr
-	err = cmd.Run()
-	if err != nil {
-		return err
+// fixFileOwner gives the owner back to the user
+func (j *Job) fixFileOwner(filename string) error {
+	if j.getSchedulePermission() == constants.SchedulePermissionSystem {
+		return nil
 	}
-
-	return nil
+	if os.Geteuid() != 0 {
+		return nil
+	}
+	// this is the case of a launchd agent supposed to be of type user, but created by root
+	// well it doesn't even seem to work anyway
+	return os.Chown(filename, os.Getuid(), os.Getgid())
 }
 
 // removeJob stops and unloads the agent from launchd, then removes the configuration file
 func (j *Job) removeJob() error {
-	ok := j.checkPermission(j.config.Permission())
+	permission := j.getSchedulePermission()
+	ok := j.checkPermission(permission)
 	if !ok {
 		return errors.New("user is not allowed to remove a system job: please restart resticprofile as root (with sudo)")
 	}
 	name := getJobName(j.config.Title(), j.config.SubTitle())
-	filename, err := getFilename(name, j.config.Permission())
+	filename, err := getFilename(name, j.getSchedulePermission())
 	if err != nil {
 		return err
 	}
 
-	if _, err := os.Stat(filename); err == nil || os.IsExist(err) {
-		// stop the service in case it's already running
-		stop := exec.Command(launchctlBin, commandStop, name)
-		stop.Stdout = os.Stdout
-		stop.Stderr = os.Stderr
-		// keep going if there's an error here
-		_ = stop.Run()
-
-		// unload the service
-		unload := exec.Command(launchctlBin, commandUnload, filename)
-		unload.Stdout = os.Stdout
-		unload.Stderr = os.Stderr
-		err = unload.Run()
-		if err != nil {
-			return err
-		}
-		err = os.Remove(filename)
-		if err != nil {
-			return err
-		}
+	if _, err := os.Stat(filename); err != nil && os.IsNotExist(err) {
+		return ErrorServiceNotFound
+	}
+	// stop the service in case it's already running
+	stop := exec.Command(launchctlBin, commandStop, name)
+	stop.Stdout = os.Stdout
+	stop.Stderr = os.Stderr
+	// keep going if there's an error here
+	_ = stop.Run()
+
+	// unload the service
+	unload := exec.Command(launchctlBin, commandUnload, filename)
+	unload.Stdout = os.Stdout
+	unload.Stderr = os.Stderr
+	err = unload.Run()
+	if err != nil {
+		return err
+	}
+	err = os.Remove(filename)
+	if err != nil {
+		return err
 	}
 
 	return nil
 }
 
 func (j *Job) displayStatus(command string) error {
+	permission := j.getSchedulePermission()
+	ok := j.checkPermission(permission)
+	if !ok {
+		return errors.New("user is not allowed view a system job: please restart resticprofile as root (with sudo)")
+	}
 	cmd := exec.Command(launchctlBin, commandList, getJobName(j.config.Title(), j.config.SubTitle()))
-	cmd.Stdout = os.Stdout
-	cmd.Stderr = os.Stderr
-	err := cmd.Run()
+	output, err := cmd.Output()
 	if cmd.ProcessState.ExitCode() == codeServiceNotFound {
 		return ErrorServiceNotFound
 	}
-	return err
-}
-
-func (j *Job) checkPermission(permission string) bool {
-	if permission == constants.SchedulePermissionUser {
-		// user mode is always available
-		return true
+	if err != nil {
+		return err
+	}
+	status := parseStatus(string(output))
+	if len(status) == 0 {
+		// output was not parsed, it could mean output format has changed
+		fmt.Println(string(output))
 	}
-	if os.Geteuid() == 0 {
-		// user has sudoed
-		return true
+	// order keys alphabetically
+	keys := make([]string, 0, len(status))
+	for key := range status {
+		keys = append(keys, key)
 	}
-	// last case is system (or undefined) + no sudo
-	return false
+	sort.Strings(keys)
+	writer := tabwriter.NewWriter(os.Stdout, 0, 0, 0, ' ', tabwriter.AlignRight)
+	for _, key := range keys {
+		fmt.Fprintf(writer, "%s:\t %s\n", key, status[key])
+	}
+	writer.Flush()
+	fmt.Println("")
+
+	return nil
 }
 
 func getJobName(profileName, command string) string {
@@ -201,7 +248,7 @@ func getJobName(profileName, command string) string {
 
 func getFilename(name, permission string) (string, error) {
 	if permission == constants.SchedulePermissionSystem {
-		return path.Join(GlobalDaemons, name+agentExtension), nil
+		return path.Join(GlobalDaemons, name+daemonExtension), nil
 	}
 	home, err := os.UserHomeDir()
 	if err != nil {
@@ -279,3 +326,16 @@ func setCalendarIntervalValueFromType(entry *CalendarInterval, value int, typeVa
 		(*entry)["Minute"] = value
 	}
 }
+
+func parseStatus(status string) map[string]string {
+	expr := regexp.MustCompile(`^\s*"(\w+)"\s*=\s*(.*);$`)
+	lines := strings.Split(status, "\n")
+	output := make(map[string]string, len(lines))
+	for _, line := range lines {
+		match := expr.FindStringSubmatch(line)
+		if len(match) == 3 {
+			output[match[1]] = strings.Trim(match[2], "\"")
+		}
+	}
+	return output
+}

schedule/schedule_darwin_test.go

@@ -71,3 +71,36 @@ func TestGetCalendarIntervalsFromScheduleTree(t *testing.T) {
 		})
 	}
 }
+
+func TestParseStatus(t *testing.T) {
+	status := `{
+	"StandardOutPath" = "local.resticprofile.self.check.log";
+	"LimitLoadToSessionType" = "Aqua";
+	"StandardErrorPath" = "local.resticprofile.self.check.log";
+	"Label" = "local.resticprofile.self.check";
+	"OnDemand" = true;
+	"LastExitStatus" = 0;
+	"Program" = "/Users/go/src/github.com/creativeprojects/resticprofile/resticprofile";
+	"ProgramArguments" = (
+		"/Users/go/src/github.com/creativeprojects/resticprofile/resticprofile";
+		"--no-ansi";
+		"--config";
+		"examples/dev.yaml";
+		"--name";
+		"self";
+		"check";
+	);
+};`
+	expected := map[string]string{
+		"StandardOutPath":        "local.resticprofile.self.check.log",
+		"LimitLoadToSessionType": "Aqua",
+		"StandardErrorPath":      "local.resticprofile.self.check.log",
+		"Label":                  "local.resticprofile.self.check",
+		"OnDemand":               "true",
+		"LastExitStatus":         "0",
+		"Program":                "/Users/go/src/github.com/creativeprojects/resticprofile/resticprofile",
+	}
+
+	output := parseStatus(status)
+	assert.Equal(t, expected, output)
+}