feat: restart to apply update, privileged helper, rollback

internal/infrastructure/update/systemdUnits.go

@@ -0,0 +1,104 @@
+package update
+
+import (
+	domain "RenewCMS/internal/domain/update"
+	"os"
+	"path/filepath"
+	"strconv"
+	"strings"
+)
+
+const (
+	systemUnitDirectory = "/etc/systemd/system"
+	unitFilePermissions = 0o644
+	unitFileSuffix      = ".service"
+)
+
+type SystemdUnits struct {
+	directory string
+}
+
+var (
+	_ domain.UnitWriter     = &SystemdUnits{}
+	_ domain.ServiceLocator = &SystemdUnits{}
+)
+
+func NewSystemdUnits() *SystemdUnits {
+	return NewSystemdUnitsIn(systemUnitDirectory)
+}
+
+func NewSystemdUnitsIn(directory string) *SystemdUnits {
+	return &SystemdUnits{directory: directory}
+}
+
+func (u *SystemdUnits) Write(name string, content string) error {
+	return os.WriteFile(filepath.Join(u.directory, name), []byte(content), unitFilePermissions)
+}
+
+func (u *SystemdUnits) Remove(name string) (bool, error) {
+	return removeFile(filepath.Join(u.directory, name))
+}
+
+func (u *SystemdUnits) Locate(name string) (domain.ServiceDescription, bool) {
+	content, err := os.ReadFile(filepath.Join(u.directory, name+unitFileSuffix))
+	if err != nil {
+		return domain.ServiceDescription{}, false
+	}
+	description := ParseServiceUnit(string(content))
+	description.Name = name
+	return description, true
+}
+
+func (u *SystemdUnits) PortFromEnvironmentFile(path string) (string, bool) {
+	if path == "" {
+		return "", false
+	}
+	content, err := os.ReadFile(path)
+	if err != nil {
+		return "", false
+	}
+	return portFromEnvironment(string(content))
+}
+
+func ParseServiceUnit(content string) domain.ServiceDescription {
+	var description domain.ServiceDescription
+	for _, line := range strings.Split(content, "\n") {
+		key, value, found := strings.Cut(strings.TrimSpace(line), "=")
+		if !found {
+			continue
+		}
+		switch key {
+		case "ExecStart":
+			description.BinaryPath = firstUnitPath(value, "@-:+!")
+		case "EnvironmentFile":
+			description.EnvironmentFile = firstUnitPath(value, "-")
+		case "ReadWritePaths":
+			if description.DataDir == "" {
+				description.DataDir = firstUnitPath(value, "-+!")
+			}
+		}
+	}
+	return description
+}
+
+func firstUnitPath(value string, prefixes string) string {
+	fields := strings.Fields(value)
+	if len(fields) == 0 {
+		return ""
+	}
+	return strings.Trim(strings.TrimLeft(fields[0], prefixes), `"`)
+}
+
+func portFromEnvironment(content string) (string, bool) {
+	for _, line := range strings.Split(content, "\n") {
+		key, value, found := strings.Cut(strings.TrimSpace(line), "=")
+		if !found || strings.TrimSpace(key) != "PORT" {
+			continue
+		}
+		port := strings.Trim(strings.TrimSpace(value), `"'`)
+		if _, err := strconv.Atoi(port); err == nil {
+			return port, true
+		}
+	}
+	return "", false
+}