Make service install converge: stop running service, refresh binary/config only on change, restart only if it was running

This commit is contained in:
mram
2026-09-21 08:30:55 +02:00
parent da02457fd5
commit 1394a76eea
4 changed files with 227 additions and 54 deletions
+4
View File
@@ -118,6 +118,10 @@ as the virtual account `NT SERVICE\gpu-turnstile` (low-privilege,
per-service, no password); the installer automatically grants it write
access to the install and data directories — nothing else to do.
Re-running `--install-service` is safe: it stops a running service,
replaces the installed binary only if it changed, fixes the registration
only where it drifted, and restarts the service only if it was running.
### Run natively on Linux (systemd)
The same binary works on Linux. Install it as a systemd service as root:
+6
View File
@@ -176,6 +176,12 @@ prompt instead of failing — the command relaunches itself elevated, waits
for the child, and mirrors its exit code. The legacy form
`gpu-turnstile service install|remove` does the same thing.
Re-running install on an already-registered service converges instead of
failing: a running service is stopped first, the installed binary copy is
refreshed only when the content differs, the registration (Windows service
config / systemd unit) is updated only where it drifted, and the service is
started again only if it was running before.
By default install creates the canonical layout and copies the binary into
it (Windows: `%ProgramFiles%\gpu-turnstile\`, plus
`%ProgramData%\gpu-turnstile\` for logs; Linux: `/var/lib/gpu-turnstile/`
+60 -8
View File
@@ -6,6 +6,7 @@
package service
import (
"bytes"
"context"
"fmt"
"io"
@@ -126,6 +127,12 @@ func copyFile(src, dst string, mode os.FileMode) error {
// copyBin=false the current executable location and config path are
// registered as-is instead. Needs root.
//
// Re-running install converges an existing unit instead of failing: it is
// stopped first if active, the installed binary is replaced only when the
// content differs, the unit file is rewritten (followed by daemon-reload)
// only when it changed, and the service is started again only if it was
// active before.
//
// The binary lives in the StateDirectory rather than /usr/local/sbin on
// purpose: replacing a running binary needs write access to its
// *directory*, and granting the sandboxed service user write access to a
@@ -139,6 +146,16 @@ func Install(configPath string, copyBin bool) error {
if abs, absErr := filepath.Abs(exe); absErr == nil {
exe = abs
}
unit := Name + ".service"
_, statErr := os.Stat(unitPath)
fresh := os.IsNotExist(statErr)
wasRunning := exec.Command("systemctl", "is-active", "--quiet", unit).Run() == nil
if wasRunning {
if out, err := exec.Command("systemctl", "stop", unit).CombinedOutput(); err != nil {
return fmt.Errorf("systemctl stop (run as root): %w (%s)", err, out)
}
}
cfg := etcConfig
if copyBin {
if err := os.MkdirAll(stateDir, 0o755); err != nil {
@@ -146,8 +163,10 @@ func Install(configPath string, copyBin bool) error {
}
installedExe := filepath.Join(stateDir, Name)
if exe != installedExe {
if err := copyFile(exe, installedExe, 0o755); err != nil {
return fmt.Errorf("install binary to %s: %w", installedExe, err)
if same, _ := sameFileContent(exe, installedExe); !same {
if err := copyFile(exe, installedExe, 0o755); err != nil {
return fmt.Errorf("install binary to %s: %w", installedExe, err)
}
}
}
exe = installedExe
@@ -161,18 +180,51 @@ func Install(configPath string, copyBin bool) error {
cfg = abs
}
}
if err := os.WriteFile(unitPath, []byte(renderUnit(exe, cfg)), 0o644); err != nil {
return fmt.Errorf("write %s (run as root): %w", unitPath, err)
rendered := renderUnit(exe, cfg)
if old, _ := os.ReadFile(unitPath); string(old) != rendered {
if err := os.WriteFile(unitPath, []byte(rendered), 0o644); err != nil {
return fmt.Errorf("write %s (run as root): %w", unitPath, err)
}
if out, err := exec.Command("systemctl", "daemon-reload").CombinedOutput(); err != nil {
return fmt.Errorf("systemctl daemon-reload: %w (%s)", err, out)
}
}
if out, err := exec.Command("systemctl", "daemon-reload").CombinedOutput(); err != nil {
return fmt.Errorf("systemctl daemon-reload: %w (%s)", err, out)
if fresh {
if out, err := exec.Command("systemctl", "enable", "--now", unit).CombinedOutput(); err != nil {
return fmt.Errorf("systemctl enable --now: %w (%s)", err, out)
}
return nil
}
if out, err := exec.Command("systemctl", "enable", "--now", Name+".service").CombinedOutput(); err != nil {
return fmt.Errorf("systemctl enable --now: %w (%s)", err, out)
if exec.Command("systemctl", "is-enabled", "--quiet", unit).Run() != nil {
if out, err := exec.Command("systemctl", "enable", unit).CombinedOutput(); err != nil {
return fmt.Errorf("systemctl enable: %w (%s)", err, out)
}
}
if wasRunning {
if out, err := exec.Command("systemctl", "start", unit).CombinedOutput(); err != nil {
return fmt.Errorf("systemctl start: %w (%s)", err, out)
}
}
return nil
}
// sameFileContent reports whether two files hold identical bytes. A missing
// destination is simply "different".
func sameFileContent(a, b string) (bool, error) {
ba, err := os.ReadFile(a)
if err != nil {
return false, err
}
bb, err := os.ReadFile(b)
if os.IsNotExist(err) {
return false, nil
}
if err != nil {
return false, err
}
return bytes.Equal(ba, bb), nil
}
// Remove stops and disables the service and deletes the unit file and the
// installed binary. The config file in /etc is left in place (user data).
func Remove() error {
+157 -46
View File
@@ -8,6 +8,7 @@
package service
import (
"bytes"
"context"
"errors"
"fmt"
@@ -109,6 +110,12 @@ func (h *handler) Execute(_ []string, requests <-chan svc.ChangeRequest, status
// config file if it lives elsewhere. The grants must come after
// CreateService: the virtual account's SID only exists once the service is
// registered.
//
// Re-running install on an existing service converges instead of failing:
// the service is stopped first if running (so the binary can be replaced),
// the installed binary is refreshed only when the content differs, the
// registration is updated only where it drifted, and the service is
// started again only if it was running before.
func Install(configPath string, copyBin bool) error {
exe, err := os.Executable()
if err != nil {
@@ -123,14 +130,38 @@ func Install(configPath string, copyBin bool) error {
}
}
m, err := mgr.Connect()
if err != nil {
return fmt.Errorf("connect to service manager (run as administrator): %w", err)
}
defer m.Disconnect()
// An existing service is converged, not an error. Stop it first so the
// binary copy can be replaced, and remember whether to start it again.
var s *mgr.Service
wasRunning := false
if existing, openErr := m.OpenService(Name); openErr == nil {
s = existing
defer s.Close()
if st, qErr := s.Query(); qErr == nil &&
(st.State == svc.Running || st.State == svc.StartPending) {
wasRunning = true
if err := stopAndWait(s); err != nil {
return err
}
}
}
installDir, _ := installDirs()
if copyBin && !strings.EqualFold(filepath.Dir(exe), installDir) {
if err := os.MkdirAll(installDir, 0o755); err != nil {
return fmt.Errorf("create %s: %w", installDir, err)
}
installedExe := filepath.Join(installDir, "gpu-turnstile.exe")
if err := copyFile(exe, installedExe); err != nil {
return fmt.Errorf("copy binary to %s: %w", installedExe, err)
if same, _ := sameFileContent(exe, installedExe); !same {
if err := copyFile(exe, installedExe); err != nil {
return fmt.Errorf("copy binary to %s: %w", installedExe, err)
}
}
exe = installedExe
targetCfg := filepath.Join(installDir, "gpu-turnstile.env")
@@ -141,44 +172,138 @@ func Install(configPath string, copyBin bool) error {
configPath = targetCfg
}
}
m, err := mgr.Connect()
if err != nil {
return fmt.Errorf("connect to service manager (run as administrator): %w", err)
}
defer m.Disconnect()
binPath := fmt.Sprintf(`"%s" -config "%s"`, exe, configPath)
s, err := m.CreateService(Name, binPath, mgr.Config{
StartType: mgr.StartAutomatic,
DisplayName: "gpu-turnstile",
Description: "GPU arbitration proxy for Ollama and ComfyUI",
ServiceStartName: virtualAccount,
})
if err != nil {
return fmt.Errorf("create service: %w", err)
}
defer s.Close()
restart := mgr.RecoveryAction{Type: mgr.ServiceRestart, Delay: 5 * time.Second}
if err := s.SetRecoveryActions([]mgr.RecoveryAction{restart, restart, restart}, 24*60*60); err != nil {
if s == nil {
s, err = m.CreateService(Name, binPath, mgr.Config{
StartType: mgr.StartAutomatic,
DisplayName: "gpu-turnstile",
Description: "GPU arbitration proxy for Ollama and ComfyUI",
ServiceStartName: virtualAccount,
})
if err != nil {
return fmt.Errorf("create service: %w", err)
}
defer s.Close()
if err := ensureRecovery(s); err != nil {
s.Delete() // roll back so a retry starts clean
return err
}
if err := grantAll(exe, configPath); err != nil {
s.Delete() // roll back so a retry starts clean
return err
}
// Best effort: start now instead of waiting for the next boot. A
// missing config (no consumer URLs) fails the start; the service stays
// registered and can be started once the config exists.
s.Start()
return nil
}
// Existing service: update the registration only where it drifted.
cur, err := s.Config()
if err != nil {
return fmt.Errorf("query service config: %w", err)
}
const displayName = "gpu-turnstile"
const description = "GPU arbitration proxy for Ollama and ComfyUI"
if cur.BinaryPathName != binPath ||
cur.StartType != mgr.StartAutomatic ||
cur.ServiceStartName != virtualAccount ||
cur.DisplayName != displayName ||
cur.Description != description {
upd := cur
upd.BinaryPathName = binPath
upd.StartType = mgr.StartAutomatic
upd.ServiceStartName = virtualAccount
upd.DisplayName = displayName
upd.Description = description
if err := s.UpdateConfig(upd); err != nil {
return fmt.Errorf("update service config: %w", err)
}
}
if err := ensureRecovery(s); err != nil {
return err
}
// Idempotent: re-assert the virtual account's ACLs (granting an
// existing ACE is a no-op).
if err := grantAll(exe, configPath); err != nil {
return err
}
if wasRunning {
if err := s.Start(); err != nil {
return fmt.Errorf("start service: %w", err)
}
}
return nil
}
// ensureRecovery makes sure the service restarts 5s after a failure — the
// mechanism that also brings up a staged update. The current actions are
// queried first so an up-to-date service is left untouched.
func ensureRecovery(s *mgr.Service) error {
want := mgr.RecoveryAction{Type: mgr.ServiceRestart, Delay: 5 * time.Second}
actions, err := s.RecoveryActions()
onFailure, flagErr := s.RecoveryActionsOnNonCrashFailures()
if err == nil && flagErr == nil && onFailure && len(actions) == 3 {
ok := true
for _, a := range actions {
if a.Type != want.Type || a.Delay != want.Delay {
ok = false
}
}
if ok {
return nil
}
}
if err := s.SetRecoveryActions([]mgr.RecoveryAction{want, want, want}, 24*60*60); err != nil {
return fmt.Errorf("set recovery actions: %w", err)
}
if err := s.SetRecoveryActionsOnNonCrashFailures(true); err != nil {
return fmt.Errorf("set failure actions flag: %w", err)
}
if err := grantAll(exe, configPath); err != nil {
s.Delete() // roll back so a retry starts clean
return err
}
// Best effort: start now instead of waiting for the next boot. A
// missing config (no consumer URLs) fails the start; the service stays
// registered and can be started once the config exists.
s.Start()
return nil
}
// stopAndWait stops the service and waits up to 30s for the stopped state.
func stopAndWait(s *mgr.Service) error {
if _, err := s.Control(svc.Stop); err != nil {
return fmt.Errorf("stop service: %w", err)
}
deadline := time.Now().Add(30 * time.Second)
for {
st, err := s.Query()
if err != nil {
return fmt.Errorf("query service: %w", err)
}
if st.State == svc.Stopped {
return nil
}
if time.Now().After(deadline) {
return fmt.Errorf("service did not stop within 30s")
}
time.Sleep(300 * time.Millisecond)
}
}
// sameFileContent reports whether two files hold identical bytes. A missing
// destination is simply "different".
func sameFileContent(a, b string) (bool, error) {
ba, err := os.ReadFile(a)
if err != nil {
return false, err
}
bb, err := os.ReadFile(b)
if os.IsNotExist(err) {
return false, nil
}
if err != nil {
return false, err
}
return bytes.Equal(ba, bb), nil
}
// copyFile copies src to dst (0755 on the new file).
func copyFile(src, dst string) error {
in, err := os.Open(src)
@@ -374,22 +499,8 @@ func RestartIfRunning() (bool, error) {
if st.State != svc.Running && st.State != svc.StartPending {
return false, nil
}
if _, err := s.Control(svc.Stop); err != nil {
return false, fmt.Errorf("stop service: %w", err)
}
deadline := time.Now().Add(30 * time.Second)
for {
st, err = s.Query()
if err != nil {
return false, fmt.Errorf("query service: %w", err)
}
if st.State == svc.Stopped {
break
}
if time.Now().After(deadline) {
return false, fmt.Errorf("service did not stop within 30s")
}
time.Sleep(300 * time.Millisecond)
if err := stopAndWait(s); err != nil {
return false, err
}
if err := s.Start(); err != nil {
return false, fmt.Errorf("start service: %w", err)