Single omc session

pyproject.toml

@@ -11,6 +11,7 @@ requires-python = ">=3.10"
 dependencies = [
     "matplotlib>=3.8,<4",
     "msgpack>=1.0,<2",
+    "OMPython>=3.6,<5",
     "PySide6>=6.7,<7",
 ]
 

src/bedit_gui/application.py

@@ -21,6 +21,7 @@ from bedit_gui.services.application_settings import ApplicationSettings
 from bedit_gui.services.clipboard import ClipboardService
 from bedit_gui.views.main_window import MainWindow
 from bedit_gui.versions import BEDIT_VERSION
+from bedit_simulation import OpenModelicaRunner, compile_component_sync
 
 def parse_arguments():
     parser = argparse.ArgumentParser(exit_on_error=False)
@@ -46,6 +47,8 @@ def main() -> int:
     app.setApplicationVersion(BEDIT_VERSION)
 
     settings = ApplicationSettings()
+    omc_runner = OpenModelicaRunner()
+    app.aboutToQuit.connect(omc_runner.close)
     document = Document(app)
     window = MainWindow(settings.snap_to_grid_size)
     window.ui.actionAbout.triggered.connect(lambda: QMessageBox.about(window, "About BEdit", f"BEdit {BEDIT_VERSION}"))
@@ -55,7 +58,7 @@ def main() -> int:
     DocumentController(document, window)
     settings_controller = SettingsController(window, settings)
     SimulationSettingsController(document, window)
-    SimulationController(document, window)
+    SimulationController(document, window, compiler=lambda component, directory: compile_component_sync(component, directory, runner=omc_runner))
     UndoController(document, window)
     ViewMenuController(window)
     document_tree_controller = DocumentTreeController(document, window)

src/bedit_gui/controllers/simulation_file_controller.py

@@ -13,6 +13,7 @@ from bedit_gui.services.application_logging import get_logger
 from bedit_gui.simulation_models import CompiledModel, SimulationRoot
 from bedit_gui.views.dialogs.simulation_settings_dialog import SimulationSettingsDialog
 from bedit_gui.views.simulation_window import SimulationWindow
+from bedit_simulation import OpenModelicaRunner
 
 logger = get_logger(__name__)
 
@@ -20,9 +21,10 @@ logger = get_logger(__name__)
 class SimulationFileController(QObject):
     runtime_changed = Signal()
 
-    def __init__(self, window: SimulationWindow) -> None:
+    def __init__(self, window: SimulationWindow, runner: OpenModelicaRunner | None = None) -> None:
         super().__init__(window)
         self.window = window
+        self.runner = runner
         self.root: SimulationRoot | None = None
         self.compiled_model: CompiledModel | None = None
         self.path: Path | None = None
@@ -147,14 +149,14 @@ class SimulationFileController(QObject):
     def _compile_with_wait_cursor(self, path: Path, *, component: str | None, simulation: str | None) -> tuple[SimulationRoot, CompiledModel]:
         QApplication.setOverrideCursor(Qt.CursorShape.WaitCursor)
         try:
-            return load_and_compile_bedit(path, component_selector=component, simulation_selector=simulation)
+            return load_and_compile_bedit(path, component_selector=component, simulation_selector=simulation, runner=self.runner)
         finally:
             QApplication.restoreOverrideCursor()
 
     def _recompile_with_wait_cursor(self, root: SimulationRoot) -> CompiledModel:
         QApplication.setOverrideCursor(Qt.CursorShape.WaitCursor)
         try:
-            return compile_simulation_root(root)
+            return compile_simulation_root(root, runner=self.runner)
         finally:
             QApplication.restoreOverrideCursor()
 

src/bedit_gui/services/simulation_loader.py

@@ -7,7 +7,7 @@ from bedit_core.models import Component, ComponentID, Document, GraphImplementat
 from bedit_gui.models import Simulation, SimulationMethod
 from bedit_gui.services import document_files
 from bedit_gui.simulation_models import CompiledModel, SimulationRoot
-from bedit_simulation import compile_component_sync
+from bedit_simulation import OpenModelicaRunner, compile_component_sync
 
 
 def component_choices(document: Document) -> list[tuple[ComponentID, Component, str]]:
@@ -24,7 +24,7 @@ def component_choices(document: Document) -> list[tuple[ComponentID, Component,
     return choices
 
 
-def load_and_compile_bedit(path: str | Path, *, component_selector: str | None = None, simulation_selector: str | None = None, working_directory: str | Path | None = None, omc_command: str = "omc") -> tuple[SimulationRoot, CompiledModel]:
+def load_and_compile_bedit(path: str | Path, *, component_selector: str | None = None, simulation_selector: str | None = None, working_directory: str | Path | None = None, omc_command: str = "omc", runner: OpenModelicaRunner | None = None) -> tuple[SimulationRoot, CompiledModel]:
     """Open a BEdit document, resolve one launch target, and compile it."""
     if bool(component_selector) == bool(simulation_selector):
         raise ValueError("specify exactly one component or simulation settings block")
@@ -57,16 +57,16 @@ def load_and_compile_bedit(path: str | Path, *, component_selector: str | None =
         settings_name=settings_name,
         settings=settings,
     )
-    return root, _compile(component, build_directory, omc_command)
+    return root, _compile(component, build_directory, omc_command, runner)
 
 
-def compile_simulation_root(root: SimulationRoot, *, working_directory: str | Path | None = None, omc_command: str = "omc") -> CompiledModel:
+def compile_simulation_root(root: SimulationRoot, *, working_directory: str | Path | None = None, omc_command: str = "omc", runner: OpenModelicaRunner | None = None) -> CompiledModel:
     if root.source_document is None:
         raise ValueError("the simulation does not reference a BEdit source document and cannot be recompiled")
     document = document_files.load(root.source_document)
     _component_id, component, _component_path = _find_component(component_choices(document), str(root.component))
     build_directory = Path(working_directory) if working_directory is not None else Path(tempfile.mkdtemp(prefix="bedit-compiled-"))
-    return _compile(component, build_directory, omc_command)
+    return _compile(component, build_directory, omc_command, runner)
 
 
 def _find_component(choices: list[tuple[ComponentID, Component, str]], selector: str) -> tuple[ComponentID, Component, str]:
@@ -90,6 +90,6 @@ def _default_settings(component_id: ComponentID) -> Simulation:
     )
 
 
-def _compile(component: Component, working_directory: Path, omc_command: str) -> CompiledModel:
-    build = compile_component_sync(component, working_directory, omc_command=omc_command)
+def _compile(component: Component, working_directory: Path, omc_command: str, runner: OpenModelicaRunner | None) -> CompiledModel:
+    build = compile_component_sync(component, working_directory, omc_command=omc_command, runner=runner)
     return CompiledModel(build.model_name, str(build.executable.resolve()), str(build.executable.parent.resolve()), build.output, build.errors)

src/bedit_gui/simulation_application.py

@@ -14,6 +14,7 @@ from bedit_gui.simulation_models import CompiledModel
 from bedit_gui.services.application_settings import SimulationApplicationSettings
 from bedit_gui.views.simulation_window import SimulationWindow
 from bedit_gui.versions import BESIM_VERSION
+from bedit_simulation import OpenModelicaRunner
 
 
 def parse_arguments(arguments: list[str] | None = None) -> argparse.Namespace:
@@ -46,7 +47,9 @@ def main(arguments: list[str] | None = None) -> int:
     window = SimulationWindow()
     window.ui.actionAbout.triggered.connect(lambda: QMessageBox.about(window, "About BEsim", f"BEsim {BESIM_VERSION}"))
     window.ui.actionAbout_QT.triggered.connect(app.aboutQt)
-    controller = SimulationFileController(window)
+    omc_runner = OpenModelicaRunner()
+    app.aboutToQuit.connect(omc_runner.close)
+    controller = SimulationFileController(window, omc_runner)
 
     settings = SimulationApplicationSettings()
     LogController(window, settings.log_level)

src/bedit_simulation/compile.py

@@ -9,13 +9,13 @@ from .openmodelica import OpenModelicaRunner
 from .simulation import ModelBuildResult, Simulation
 
 
-async def compile_component(component: Component, working_directory: str | Path, *, omc_command: str = "omc", timeout: float | None = None) -> ModelBuildResult:
+async def compile_component(component: Component, working_directory: str | Path, *, omc_command: str = "omc", timeout: float | None = None, runner: OpenModelicaRunner | None = None) -> ModelBuildResult:
     """Compose and compile a component without creating a GUI application."""
-    simulation = Simulation(OpenModelicaRunner(omc_command, timeout=timeout))
+    simulation = Simulation(runner or OpenModelicaRunner(omc_command, timeout=timeout))
     await simulation.load(component)
     return await simulation.compile(working_directory)
 
 
-def compile_component_sync(component: Component, working_directory: str | Path, *, omc_command: str = "omc", timeout: float | None = None) -> ModelBuildResult:
+def compile_component_sync(component: Component, working_directory: str | Path, *, omc_command: str = "omc", timeout: float | None = None, runner: OpenModelicaRunner | None = None) -> ModelBuildResult:
     """Synchronous entry point for scripts and non-async suite applications."""
-    return asyncio.run(compile_component(component, working_directory, omc_command=omc_command, timeout=timeout))
+    return asyncio.run(compile_component(component, working_directory, omc_command=omc_command, timeout=timeout, runner=runner))

src/bedit_simulation/openmodelica.py

@@ -6,13 +6,15 @@ import asyncio
 import os
 import signal
 import shlex
+import shutil
 import subprocess
 import time
 from collections.abc import Callable, Mapping, Sequence
+from contextlib import suppress
 from dataclasses import dataclass
 from pathlib import Path
-from threading import Event, Thread
-from typing import Any, TypeVar
+from threading import Event, Lock, Thread
+from typing import Any, Protocol, Self, TypeVar
 
 
 @dataclass(frozen=True)
@@ -48,6 +50,15 @@ ProcessExecutor = Callable[
 _Result = TypeVar("_Result")
 
 
+class InteractiveSession(Protocol):
+    """Small part of the OMPython session API used by the runner."""
+
+    def sendExpression(self, command: str, parsed: bool = True) -> Any: ...
+
+
+SessionFactory = Callable[[tuple[str, ...], float | None], InteractiveSession]
+
+
 class OpenModelicaRunner:
     """Execute ``.mos`` scripts using an OMC command or wrapper script.
 
@@ -63,14 +74,22 @@ class OpenModelicaRunner:
         timeout: float | None = None,
         environment: Mapping[str, str] | None = None,
         executor: ProcessExecutor | None = None,
+        session_factory: SessionFactory | None = None,
+        reuse_session: bool = True,
     ) -> None:
         self.command = _command_parts(command)
         self.timeout = timeout
         self.environment = environment
         self._executor = executor or _execute_process
+        self._session_factory = session_factory or _create_interactive_session
+        self._reuse_session = reuse_session and executor is None and environment is None and len(self.command) == 1
+        self._session: InteractiveSession | None = None
+        self._session_lock = Lock()
 
     def _run(self, script: Path, working_directory: Path) -> ProcessResult:
         """Run ``script`` in ``working_directory`` and return captured output."""
+        if self._reuse_session:
+            return self._run_in_session(script, working_directory)
         command = (*self.command, str(script.resolve()))
         try:
             result = self._executor(
@@ -95,6 +114,48 @@ class OpenModelicaRunner:
             )
         return result
 
+    def _run_in_session(self, script: Path, working_directory: Path) -> ProcessResult:
+        script_path = script.resolve()
+        expression = f"runScript({_modelica_string(str(script_path))})"
+        with self._session_lock:
+            try:
+                session = self._session
+                if session is None:
+                    session = self._session_factory(self.command, self.timeout)
+                    self._session = session
+                output = session.sendExpression(expression, parsed=False)
+            except Exception as exc:  # OMPython exceptions are optional at import time
+                self._close_session_locked()
+                if isinstance(exc, OpenModelicaError):
+                    raise
+                raise OpenModelicaError(f"OpenModelica session failed: {exc}") from exc
+        return ProcessResult(command=(*self.command, str(script_path)), return_code=0, stdout=str(output), stderr="")
+
+    @property
+    def session_running(self) -> bool:
+        """Return whether this runner has started its reusable OMC session."""
+        with self._session_lock:
+            return self._session is not None
+
+    def close(self) -> None:
+        """Stop the reusable OMC session, if it has been started."""
+        with self._session_lock:
+            self._close_session_locked()
+
+    def _close_session_locked(self) -> None:
+        session = self._session
+        self._session = None
+        if session is None:
+            return
+        with suppress(Exception):
+            session.sendExpression("quit()", parsed=False)
+
+    def __enter__(self) -> Self:
+        return self
+
+    def __exit__(self, *_args: object) -> None:
+        self.close()
+
     async def run(
         self,
         script: Path,
@@ -167,6 +228,30 @@ def _command_parts(command: str | Sequence[str]) -> tuple[str, ...]:
     return parts
 
 
+def _modelica_string(value: str) -> str:
+    return '"' + value.replace("\\", "\\\\").replace('"', '\\"') + '"'
+
+
+def _create_interactive_session(command: tuple[str, ...], timeout: float | None) -> InteractiveSession:
+    if len(command) != 1:
+        raise OpenModelicaError("a reusable OpenModelica session requires a single OMC executable command")
+    executable = shutil.which(command[0])
+    if executable is None:
+        raise OpenModelicaError(f"OpenModelica command {command[0]!r} was not found")
+    try:
+        from OMPython import OMCSessionZMQ
+    except ImportError:
+        raise OpenModelicaError("reusable OpenModelica sessions require the OMPython package") from None
+    # Preserve wrapper symlinks: OMPython reconstructs ``<omhome>/bin/omc``.
+    omhome = str(Path(executable).parent.parent)
+    try:
+        if timeout is None:
+            return OMCSessionZMQ(omhome=omhome)
+        return OMCSessionZMQ(timeout=timeout, omhome=omhome)
+    except Exception as exc:
+        raise OpenModelicaError(f"OpenModelica session could not start: {exc}") from exc
+
+
 def _execute_process(
     command: Sequence[str],
     working_directory: Path,

src/bedit_simulation/simulation.py

@@ -705,6 +705,7 @@ def _load_model_script(
         ])
     return "\n".join(
         [
+            "clear();",
             f"cd({json.dumps(str(working_directory.resolve()))});",
             *load_libraries,
             f"loaded := loadFile({json.dumps(_MODEL_FILE)});",