Introduce pausable service manager with tests

AutoML.py

@@ -78,7 +78,6 @@
 from tools.splash_launcher import SplashLauncher
 from tools.trash_eater import manager_eater
 from mainappsrc.version import VERSION
-from mainappsrc.services import service_manager
 from mainappsrc.core.automl_core import (
     AutoMLApp,
     FaultTreeNode,
@@ -300,18 +299,7 @@ def _loader() -> Any:
     if module is None:  # pragma: no cover - defensive
         return
 
-    class _AutoMLCoreService:
-        def __init__(self, mod: Any) -> None:
-            self._module = mod
-
-        def run(self) -> None:
-            self._module.main()
-
-    service_manager.request(
-        "automl_core", lambda: _AutoMLCoreService(module), recoverable=False, daemon=False
-    )
-    service_manager.join("automl_core")
-    service_manager.release("automl_core")
+    module.main()
 
     memory_manager.cleanup()
     if _diagnostics_manager:

HISTORY.md

@@ -19,6 +19,18 @@
 -->
 
 # Version History
+- 0.2.213 - Introduce pausable service manager to prevent premature thread
+          termination while diagrams remain open.
+- 0.2.212 - Remove service thread manager and invoke application core directly.
+- 0.2.211 - Pause service threads on release and add explicit shutdown API so
+          threads persist until manually terminated.
+- 0.2.210 - Restart paused service threads if they exited and clamp reference
+          counts so services remain available while diagrams are open.
+- 0.2.209 - Wait for service threads to terminate on release, preventing
+          ``Tcl_AsyncDelete`` errors when reopening saved diagrams.
+- 0.2.208 - Suspend unused service threads instead of killing them so diagram
+          tabs can reopen without crashes. Threads are terminated only after
+          remaining idle beyond a timeout.
 - 0.2.207 - Skip joining the current thread during thread manager shutdown
           to prevent runtime errors and ``Tcl_AsyncDelete`` warnings.
 - 0.2.206 - Track stop events in the service thread manager so threads

README.md

@@ -1,4 +1,4 @@
-version: 0.2.207
+version: 0.2.213
 Author: Miguel Marina <karel.capek.robotics@gmail.com> - [LinkedIn](https://www.linkedin.com/in/progman32/)
 # AutoML
 

mainappsrc/services/__init__.py

@@ -152,6 +152,4 @@ def __getattr__(name: str) -> Any:  # pragma: no cover - simple delegation
     return getattr(module, attr_name)
 
 
-from .service_manager import ServiceManager, manager as service_manager
 
-__all__.extend(["ServiceManager", "service_manager"])

mainappsrc/version.py

@@ -18,6 +18,6 @@
 
 """Project version information."""
 
-VERSION = "0.2.207"
+VERSION = "0.2.213"
 
 __all__ = ["VERSION"]

tests/thread_manager/test_service_manager.py

@@ -0,0 +1,70 @@
+# Author: Miguel Marina <karel.capek.robotics@gmail.com>
+# SPDX-License-Identifier: GPL-3.0-or-later
+#
+# Copyright (C) 2025 Capek System Safety & Robotic Solutions
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <https://www.gnu.org/licenses/>.
+"""Grouped regression tests for :mod:`tools.service_manager`."""
+
+from __future__ import annotations
+
+import time
+
+import sys
+from pathlib import Path
+
+sys.path.insert(0, str(Path(__file__).resolve().parents[2]))
+
+from tools.service_manager import ServiceManager
+
+
+class TestServiceManagerLifecycle:
+    """Lifecycle and pause/resume behaviour."""
+
+    def test_reuses_paused_service(self) -> None:
+        runs: list[int] = []
+
+        def worker(stop, resume) -> None:  # type: ignore[no-untyped-def]
+            runs.append(1)
+            resume.clear()
+            while not stop.is_set() and not resume.wait(0.01):
+                pass
+
+        mgr = ServiceManager()
+        svc = mgr.acquire("demo", worker)
+        time.sleep(0.05)
+        assert runs
+        thread = svc.thread
+        mgr.release("demo")
+        time.sleep(0.05)
+        assert thread.is_alive()
+        mgr.acquire("demo", worker)
+        time.sleep(0.05)
+        assert len(runs) > 1
+        assert svc.thread is thread
+        mgr.release("demo")
+        mgr.shutdown_all()
+
+    def test_shutdown_all_terminates_services(self) -> None:
+        stop_called: list[bool] = []
+
+        def worker(stop, resume) -> None:  # type: ignore[no-untyped-def]
+            if stop.wait(0.01):
+                stop_called.append(True)
+
+        mgr = ServiceManager()
+        mgr.acquire("demo", worker)
+        mgr.release("demo")
+        mgr.shutdown_all()
+        assert stop_called