fix: restart backend under systemd and use .sproutclaw agent dir

Restart via systemctl when running as a service, set SPROUTCLAW_CODING_AGENT_DIR
for the RPC subprocess, and add a frontend poll timeout for failed restarts.

Co-authored-by: Cursor <cursoragent@cursor.com>

backend/internal/config/config.go

@@ -32,8 +32,8 @@ type Config struct {
 
 func New() *Config {
 	port := flag.Int("port", 19133, "HTTP port")
-	agentDir := flag.String("agent-dir", "", "pi agent directory (e.g. /path/to/.pi/agent)")
-	repoRoot := flag.String("repo-root", "", "pi repo root (pi CLI cwd); defaults to two levels above agent-dir")
+	agentDir := flag.String("agent-dir", "", "SproutClaw agent directory (e.g. /path/to/.sproutclaw/agent)")
+	repoRoot := flag.String("repo-root", "", "SproutClaw repo root (CLI cwd); defaults to two levels above agent-dir")
 	dataDir := flag.String("data-dir", "", "sproutclaw-web data dir for SQLite (defaults to ./data)")
 	piCmd := flag.String("pi-cmd", "", "pi CLI command (may include args, e.g. \"node /path/tsx.mjs /path/cli.ts\")")
 	frontendDist := flag.String("frontend-dist", "", "path to frontend/dist (defaults to ../frontend/dist relative to binary)")
@@ -41,7 +41,7 @@ func New() *Config {
 
 	if *agentDir == "" {
 		cwd, _ := os.Getwd()
-		*agentDir = filepath.Join(cwd, ".pi", "agent")
+		*agentDir = filepath.Join(cwd, ".sproutclaw", "agent")
 	}
 
 	cfg := &Config{
@@ -50,7 +50,7 @@ func New() *Config {
 		RepoRoot: *repoRoot,
 		DataDir:  *dataDir,
 	}
-	// repoRoot defaults to the directory two levels above agentDir (.pi/agent -> repo root)
+	// repoRoot defaults to the directory two levels above agentDir (.sproutclaw/agent -> repo root)
 	if cfg.RepoRoot == "" {
 		cfg.RepoRoot = filepath.Dir(filepath.Dir(*agentDir))
 	}

backend/internal/handlers/restart.go

@@ -0,0 +1,99 @@
+package handlers
+
+import (
+	"log"
+	"net/http"
+	"os"
+	"os/exec"
+	"runtime"
+	"strings"
+	"time"
+
+	"github.com/gin-gonic/gin"
+)
+
+const defaultSystemdUnit = "sproutclaw-web.service"
+
+func handleRestart() gin.HandlerFunc {
+	return func(c *gin.Context) {
+		c.JSON(http.StatusOK, gin.H{"ok": true})
+		go func() {
+			time.Sleep(300 * time.Millisecond)
+			if unit, underSystemd := systemdServiceUnit(); underSystemd {
+				log.Printf("[restart] restarting via systemctl: %s", unit)
+				cmd := exec.Command("systemctl", "restart", unit)
+				out, err := cmd.CombinedOutput()
+				if err != nil {
+					log.Printf("[restart] systemctl restart failed: %v: %s", err, strings.TrimSpace(string(out)))
+				}
+				return
+			}
+			restartByReexec()
+		}()
+	}
+}
+
+func restartByReexec() {
+	exe, err := os.Executable()
+	if err != nil {
+		log.Printf("[restart] get executable: %v", err)
+		os.Exit(1)
+	}
+	cmd := exec.Command(exe, os.Args[1:]...)
+	cmd.Stdout = os.Stdout
+	cmd.Stderr = os.Stderr
+	if err := cmd.Start(); err != nil {
+		log.Printf("[restart] start new process: %v", err)
+		os.Exit(1)
+	}
+	os.Exit(0)
+}
+
+func systemdServiceUnit() (string, bool) {
+	if runtime.GOOS != "linux" {
+		return "", false
+	}
+	if os.Getenv("INVOCATION_ID") == "" && !inSystemdCgroup() {
+		return "", false
+	}
+	if unit := strings.TrimSpace(os.Getenv("SPROUTCLAW_WEB_SYSTEMD_UNIT")); unit != "" {
+		return normalizeSystemdUnit(unit), true
+	}
+	if unit := readSystemdUnitFromCgroup(); unit != "" {
+		return unit, true
+	}
+	return defaultSystemdUnit, true
+}
+
+func normalizeSystemdUnit(name string) string {
+	if strings.HasSuffix(name, ".service") {
+		return name
+	}
+	return name + ".service"
+}
+
+func inSystemdCgroup() bool {
+	data, err := os.ReadFile("/proc/self/cgroup")
+	if err != nil {
+		return false
+	}
+	return strings.Contains(string(data), ".service")
+}
+
+func readSystemdUnitFromCgroup() string {
+	data, err := os.ReadFile("/proc/self/cgroup")
+	if err != nil {
+		return ""
+	}
+	for _, line := range strings.Split(string(data), "\n") {
+		idx := strings.LastIndex(line, "/")
+		if idx < 0 {
+			continue
+		}
+		name := line[idx+1:]
+		if strings.HasSuffix(name, ".service") {
+			return name
+		}
+	}
+	return ""
+}

backend/internal/handlers/settings.go

@@ -2,10 +2,8 @@ package handlers
 
 import (
 	"fmt"
-	"log"
 	"net/http"
 	"os"
-	"os/exec"
 	"runtime"
 	"strings"
 	"sync"
@@ -37,28 +35,6 @@ func RegisterSettings(r *gin.RouterGroup, cfg *config.Config, database *db.DB, p
 
 var processStartTime = time.Now()
 
-func handleRestart() gin.HandlerFunc {
-	return func(c *gin.Context) {
-		c.JSON(http.StatusOK, gin.H{"ok": true})
-		go func() {
-			time.Sleep(300 * time.Millisecond)
-			exe, err := os.Executable()
-			if err != nil {
-				log.Printf("[restart] get executable: %v", err)
-				os.Exit(1)
-			}
-			cmd := exec.Command(exe, os.Args[1:]...)
-			cmd.Stdout = os.Stdout
-			cmd.Stderr = os.Stderr
-			if err := cmd.Start(); err != nil {
-				log.Printf("[restart] start new process: %v", err)
-				os.Exit(1)
-			}
-			os.Exit(0)
-		}()
-	}
-}
-
 func handleGetSettings(cfg *config.Config, database *db.DB) gin.HandlerFunc {
 	return func(c *gin.Context) {
 		systemPrompt, _ := services.ReadSystemPrompt(cfg.SystemPromptFile)

backend/internal/rpc/client.go

@@ -80,7 +80,7 @@ func NewClient(piCmd string, piArgs []string, repoRoot, agentDir string, onExit
 	args := append(append([]string{}, piArgs...), "--mode", "rpc")
 	cmd := exec.Command(piCmd, args...)
 	cmd.Dir = repoRoot
-	cmd.Env = append(os.Environ(), fmt.Sprintf("PI_CODING_AGENT_DIR=%s", agentDir))
+	cmd.Env = append(os.Environ(), fmt.Sprintf("SPROUTCLAW_CODING_AGENT_DIR=%s", agentDir))
 
 	log.Printf("[sproutclaw-web] launching pi RPC: %s %s (cwd=%s)", piCmd, strings.Join(args, " "), repoRoot)