inital commit

Overlord-Client/cmd/agent/persistence/persistence_linux.go

@@ -0,0 +1,227 @@
+//go:build linux
+// +build linux
+
+package persistence
+
+import (
+	"fmt"
+	"io"
+	"os"
+	"os/user"
+	"path/filepath"
+	"text/template"
+)
+
+const systemdService = `[Unit]
+Description=Overlord Agent
+After=network.target
+
+[Service]
+Type=simple
+ExecStart={{.ExePath}}
+Restart=always
+RestartSec=10
+
+[Install]
+WantedBy=default.target
+`
+
+const desktopEntry = `[Desktop Entry]
+Type=Application
+Name=Overlord Agent
+Exec={{.ExePath}}
+Hidden=false
+NoDisplay=false
+X-GNOME-Autostart-enabled=true
+`
+
+func getSystemdPath() (string, error) {
+	usr, err := user.Current()
+	if err != nil {
+		return "", err
+	}
+	return filepath.Join(usr.HomeDir, ".config", "systemd", "user", "overlord-agent.service"), nil
+}
+
+func getAutostartPath() (string, error) {
+	usr, err := user.Current()
+	if err != nil {
+		return "", err
+	}
+	return filepath.Join(usr.HomeDir, ".config", "autostart", "overlord-agent.desktop"), nil
+}
+
+func getTargetPath() (string, error) {
+	usr, err := user.Current()
+	if err != nil {
+		return "", err
+	}
+	return filepath.Join(usr.HomeDir, ".local", "share", "overlord", "agent"), nil
+}
+
+func install(exePath string) error {
+
+	targetPath, err := getTargetPath()
+	if err != nil {
+		return fmt.Errorf("failed to get target path: %w", err)
+	}
+
+	dir := filepath.Dir(targetPath)
+	if err := os.MkdirAll(dir, 0755); err != nil {
+		return fmt.Errorf("failed to create overlord directory: %w", err)
+	}
+
+	if err := replaceExecutable(exePath, targetPath); err != nil {
+		return err
+	}
+
+	if err := installSystemd(targetPath); err == nil {
+		return nil
+	}
+
+	return installAutostart(targetPath)
+}
+
+func replaceExecutable(exePath, targetPath string) error {
+	srcFile, err := os.Open(exePath)
+	if err != nil {
+		return fmt.Errorf("failed to open source executable: %w", err)
+	}
+	defer srcFile.Close()
+
+	dir := filepath.Dir(targetPath)
+	tmpFile, err := os.CreateTemp(dir, "agent-*.tmp")
+	if err != nil {
+		return fmt.Errorf("failed to create temp executable: %w", err)
+	}
+	tmpPath := tmpFile.Name()
+	defer func() {
+		_ = tmpFile.Close()
+		_ = os.Remove(tmpPath)
+	}()
+
+	if _, err := io.Copy(tmpFile, srcFile); err != nil {
+		return fmt.Errorf("failed to copy executable: %w", err)
+	}
+	if err := tmpFile.Sync(); err != nil {
+		return fmt.Errorf("failed to sync temp file: %w", err)
+	}
+	if err := tmpFile.Close(); err != nil {
+		return fmt.Errorf("failed to close temp file: %w", err)
+	}
+
+	if err := os.Rename(tmpPath, targetPath); err != nil {
+		if removeErr := os.Remove(targetPath); removeErr == nil {
+			if err = os.Rename(tmpPath, targetPath); err == nil {
+				return nil
+			}
+		}
+		return fmt.Errorf("failed to replace executable at %s: %w", targetPath, err)
+	}
+
+	if err := os.Chmod(targetPath, 0755); err != nil {
+		return fmt.Errorf("failed to set executable permissions: %w", err)
+	}
+
+	return nil
+}
+
+func installSystemd(exePath string) error {
+	servicePath, err := getSystemdPath()
+	if err != nil {
+		return err
+	}
+
+	dir := filepath.Dir(servicePath)
+	if err := os.MkdirAll(dir, 0755); err != nil {
+		return fmt.Errorf("failed to create systemd directory: %w", err)
+	}
+
+	file, err := os.Create(servicePath)
+	if err != nil {
+		return fmt.Errorf("failed to create service file: %w", err)
+	}
+	defer file.Close()
+
+	tmpl, err := template.New("service").Parse(systemdService)
+	if err != nil {
+		return fmt.Errorf("failed to parse template: %w", err)
+	}
+
+	data := struct {
+		ExePath string
+	}{
+		ExePath: exePath,
+	}
+
+	if err := tmpl.Execute(file, data); err != nil {
+		return fmt.Errorf("failed to write service file: %w", err)
+	}
+
+	return nil
+}
+
+func configure(exePath string) error {
+	if err := installSystemd(exePath); err == nil {
+		return nil
+	}
+	return installAutostart(exePath)
+}
+
+func installAutostart(exePath string) error {
+	autostartPath, err := getAutostartPath()
+	if err != nil {
+		return err
+	}
+
+	dir := filepath.Dir(autostartPath)
+	if err := os.MkdirAll(dir, 0755); err != nil {
+		return fmt.Errorf("failed to create autostart directory: %w", err)
+	}
+
+	file, err := os.Create(autostartPath)
+	if err != nil {
+		return fmt.Errorf("failed to create desktop entry: %w", err)
+	}
+	defer file.Close()
+
+	tmpl, err := template.New("desktop").Parse(desktopEntry)
+	if err != nil {
+		return fmt.Errorf("failed to parse template: %w", err)
+	}
+
+	data := struct {
+		ExePath string
+	}{
+		ExePath: exePath,
+	}
+
+	if err := tmpl.Execute(file, data); err != nil {
+		return fmt.Errorf("failed to write desktop entry: %w", err)
+	}
+
+	return nil
+}
+
+func uninstall() error {
+
+	var lastErr error
+
+	if servicePath, err := getSystemdPath(); err == nil {
+		if err := os.Remove(servicePath); err != nil && !os.IsNotExist(err) {
+			lastErr = fmt.Errorf("failed to remove systemd service: %w", err)
+		}
+	}
+
+	if autostartPath, err := getAutostartPath(); err == nil {
+		if err := os.Remove(autostartPath); err != nil && !os.IsNotExist(err) {
+			lastErr = fmt.Errorf("failed to remove autostart entry: %w", err)
+		}
+	}
+
+	if targetPath, err := getTargetPath(); err == nil {
+		os.Remove(targetPath)
+	}
+
+	return lastErr
+}