[ModelicaSystem] fix usage of relative paths

OMPython/ModelicaSystem.py

@@ -38,6 +38,7 @@
 import logging
 import numbers
 import os
+import pathlib
 import queue
 import textwrap
 import threading
@@ -124,9 +125,12 @@ def __init__(
             self,
             session: OMCSessionZMQ,
             runpath: OMCPath,
-            modelname: str,
+            modelname: Optional[str] = None,
             timeout: Optional[float] = None,
     ) -> None:
+        if modelname is None:
+            raise ModelicaSystemError("Missing model name!")
+
         self._session = session
         self._runpath = runpath
         self._model_name = modelname
@@ -321,60 +325,25 @@ def parse_simflags(simflags: str) -> dict[str, Optional[str | dict[str, Any] | n
 class ModelicaSystem:
     def __init__(
             self,
-            fileName: Optional[str | os.PathLike] = None,
-            modelName: Optional[str] = None,
-            lmodel: Optional[list[str | tuple[str, str]]] = None,
             commandLineOptions: Optional[list[str]] = None,
-            variableFilter: Optional[str] = None,
             customBuildDirectory: Optional[str | os.PathLike] = None,
             omhome: Optional[str] = None,
             omc_process: Optional[OMCProcess] = None,
-            build: bool = True,
     ) -> None:
-        """Initialize, load and build a model.
-
-        The constructor loads the model file and builds it, generating exe and
-        xml files, etc.
+        """Create a ModelicaSystem instance. To define the model use model() or convertFmu2Mo().
 
         Args:
-            fileName: Path to the model file. Either absolute or relative to
-              the current working directory.
-            modelName: The name of the model class. If it is contained within
-              a package, "PackageName.ModelName" should be used.
-            lmodel: List of libraries to be loaded before the model itself is
-              loaded. Two formats are supported for the list elements:
-              lmodel=["Modelica"] for just the library name
-              and lmodel=[("Modelica","3.2.3")] for specifying both the name
-              and the version.
             commandLineOptions: List with extra command line options as elements. The list elements are
               provided to omc via setCommandLineOptions(). If set, the default values will be overridden.
               To disable any command line options, use an empty list.
-            variableFilter: A regular expression. Only variables fully
-              matching the regexp will be stored in the result file.
-              Leaving it unspecified is equivalent to ".*".
             customBuildDirectory: Path to a directory to be used for temporary
               files like the model executable. If left unspecified, a tmp
               directory will be created.
-            omhome: OPENMODELICAHOME value to be used when creating the OMC
-              session.
+            omhome: path to OMC to be used when creating the OMC session (see OMCSessionZMQ).
             omc_process: definition of a (local) OMC process to be used. If
               unspecified, a new local session will be created.
-            build: Boolean controlling whether or not the model should be
-              built when constructor is called. If False, the constructor
-              simply loads the model without compiling.
-
-        Examples:
-            mod = ModelicaSystem("ModelicaModel.mo", "modelName")
-            mod = ModelicaSystem("ModelicaModel.mo", "modelName", ["Modelica"])
-            mod = ModelicaSystem("ModelicaModel.mo", "modelName", [("Modelica","3.2.3"), "PowerSystems"])
         """
 
-        if fileName is None and modelName is None and not lmodel:  # all None
-            raise ModelicaSystemError("Cannot create ModelicaSystem object without any arguments")
-
-        if modelName is None:
-            raise ModelicaSystemError("A modelname must be provided (argument modelName)!")
-
         self._quantities: list[dict[str, Any]] = []
         self._params: dict[str, str] = {}  # even numerical values are stored as str
         self._inputs: dict[str, list | None] = {}
@@ -408,44 +377,98 @@ def __init__(
         for opt in commandLineOptions:
             self.setCommandLineOptions(commandLineOptions=opt)
 
-        if lmodel is None:
-            lmodel = []
-
-        if not isinstance(lmodel, list):
-            raise ModelicaSystemError(f"Invalid input type for lmodel: {type(lmodel)} - list expected!")
-
-        self._lmodel = lmodel  # may be needed if model is derived from other model
-        self._model_name = modelName  # Model class name
-        if fileName is not None:
-            file_name = self._session.omcpath(fileName).resolve()
-        else:
-            file_name = None
-        self._file_name: Optional[OMCPath] = file_name  # Model file/package name
         self._simulated = False  # True if the model has already been simulated
         self._result_file: Optional[OMCPath] = None  # for storing result file
-        self._variable_filter = variableFilter
 
-        if self._file_name is not None and not self._file_name.is_file():  # if file does not exist
-            raise IOError(f"{self._file_name} does not exist!")
+        self._work_dir: OMCPath = self.setWorkDirectory(customBuildDirectory)
 
-        # set default command Line Options for linearization as
-        # linearize() will use the simulation executable and runtime
-        # flag -l to perform linearization
-        self.setCommandLineOptions("--linearizationDumpLanguage=python")
-        self.setCommandLineOptions("--generateSymbolicLinearization")
+        self._model_name: Optional[str] = None
+        self._libraries: Optional[list[str | tuple[str, str]]] = None
+        self._file_name: Optional[OMCPath] = None
+        self._variable_filter: Optional[str] = None
 
-        self._work_dir: OMCPath = self.setWorkDirectory(customBuildDirectory)
+    def model(
+            self,
+            name: Optional[str] = None,
+            file: Optional[str | os.PathLike] = None,
+            libraries: Optional[list[str | tuple[str, str]]] = None,
+            variable_filter: Optional[str] = None,
+            build: bool = True,
+    ) -> None:
+        """Load and build a Modelica model.
+
+        This method loads the model file and builds it if requested (build == True).
+
+        Args:
+            file: Path to the model file. Either absolute or relative to
+              the current working directory.
+            name: The name of the model class. If it is contained within
+              a package, "PackageName.ModelName" should be used.
+            libraries: List of libraries to be loaded before the model itself is
+              loaded. Two formats are supported for the list elements:
+              lmodel=["Modelica"] for just the library name
+              and lmodel=[("Modelica","3.2.3")] for specifying both the name
+              and the version.
+            variable_filter: A regular expression. Only variables fully
+              matching the regexp will be stored in the result file.
+              Leaving it unspecified is equivalent to ".*".
+            build: Boolean controlling whether the model should be
+              built when constructor is called. If False, the constructor
+              simply loads the model without compiling.
+
+        Examples:
+            mod = ModelicaSystem()
+            # and then one of the lines below
+            mod.model(name="modelName", file="ModelicaModel.mo", )
+            mod.model(name="modelName", file="ModelicaModel.mo", libraries=["Modelica"])
+            mod.model(name="modelName", file="ModelicaModel.mo", libraries=[("Modelica","3.2.3"), "PowerSystems"])
+        """
+
+        if self._model_name is not None:
+            raise ModelicaSystemError("Can not reuse this instance of ModelicaSystem "
+                                      f"defined for {repr(self._model_name)}!")
+
+        if name is None or not isinstance(name, str):
+            raise ModelicaSystemError("A model name must be provided!")
+
+        if libraries is None:
+            libraries = []
+
+        if not isinstance(libraries, list):
+            raise ModelicaSystemError(f"Invalid input type for libraries: {type(libraries)} - list expected!")
+
+        # set variables
+        self._model_name = name  # Model class name
+        self._libraries = libraries  # may be needed if model is derived from other model
+        self._variable_filter = variable_filter
+
+        if self._libraries:
+            self._loadLibrary(libraries=self._libraries)
+
+        self._file_name = None
+        if file is not None:
+            file_path = pathlib.Path(file)
+            # special handling for OMCProcessLocal - consider a relative path
+            if isinstance(self._session.omc_process, OMCProcessLocal) and not file_path.is_absolute():
+                file_path = pathlib.Path.cwd() / file_path
+            if not file_path.is_file():
+                raise IOError(f"Model file {file_path} does not exist!")
+
+            self._file_name = self.getWorkDirectory() / file_path.name
+            if (isinstance(self._session.omc_process, OMCProcessLocal)
+                    and file_path.as_posix() == self._file_name.as_posix()):
+                pass
+            elif self._file_name.is_file():
+                raise IOError(f"Simulation model file {self._file_name} exist - not overwriting!")
+            else:
+                content = file_path.read_text(encoding='utf-8')
+                self._file_name.write_text(content)
 
         if self._file_name is not None:
-            self._loadLibrary(lmodel=self._lmodel)
             self._loadFile(fileName=self._file_name)
 
-        # allow directly loading models from MSL without fileName
-        elif fileName is None and modelName is not None:
-            self._loadLibrary(lmodel=self._lmodel)
-
         if build:
-            self.buildModel(variableFilter)
+            self.buildModel(variable_filter)
 
     def session(self) -> OMCSessionZMQ:
         """
@@ -465,9 +488,9 @@ def _loadFile(self, fileName: OMCPath):
         self.sendExpression(f'loadFile("{fileName.as_posix()}")')
 
     # for loading file/package, loading model and building model
-    def _loadLibrary(self, lmodel: list):
+    def _loadLibrary(self, libraries: list):
         # load Modelica standard libraries or Modelica files if needed
-        for element in lmodel:
+        for element in libraries:
             if element is not None:
                 if isinstance(element, str):
                     if element.endswith(".mo"):
@@ -1587,9 +1610,13 @@ def _createCSVData(self, csvfile: Optional[OMCPath] = None) -> OMCPath:
 
         return csvfile
 
-    def convertMo2Fmu(self, version: str = "2.0", fmuType: str = "me_cs",
-                      fileNamePrefix: str = "<default>",
-                      includeResources: bool = True) -> str:
+    def convertMo2Fmu(
+            self,
+            version: str = "2.0",
+            fmuType: str = "me_cs",
+            fileNamePrefix: Optional[str] = None,
+            includeResources: bool = True,
+    ) -> OMCPath:
         """Translate the model into a Functional Mockup Unit.
 
         Args:
@@ -1606,24 +1633,29 @@ def convertMo2Fmu(self, version: str = "2.0", fmuType: str = "me_cs",
             '/tmp/tmpmhfx9umo/CauerLowPassAnalog.fmu'
         """
 
-        if fileNamePrefix == "<default>":
-            fileNamePrefix = self._model_name
-        if includeResources:
-            includeResourcesStr = "true"
-        else:
-            includeResourcesStr = "false"
+        if fileNamePrefix is None:
+            if self._model_name is None:
+                fileNamePrefix = "<default>"
+            else:
+                fileNamePrefix = self._model_name
+        includeResourcesStr = "true" if includeResources else "false"
+
         properties = (f'version="{version}", fmuType="{fmuType}", '
                       f'fileNamePrefix="{fileNamePrefix}", includeResources={includeResourcesStr}')
         fmu = self._requestApi(apiName='buildModelFMU', entity=self._model_name, properties=properties)
+        fmu_path = self._session.omcpath(fmu)
 
         # report proper error message
-        if not os.path.exists(fmu):
-            raise ModelicaSystemError(f"Missing FMU file: {fmu}")
+        if not fmu_path.is_file():
+            raise ModelicaSystemError(f"Missing FMU file: {fmu_path.as_posix()}")
 
-        return fmu
+        return fmu_path
 
     # to convert FMU to Modelica model
-    def convertFmu2Mo(self, fmuName):  # 20
+    def convertFmu2Mo(
+            self,
+            fmu: os.PathLike,
+    ) -> OMCPath:
         """
         In order to load FMU, at first it needs to be translated into Modelica model. This method is used to generate
         Modelica model from the given FMU. It generates "fmuName_me_FMU.mo".
@@ -1632,13 +1664,24 @@ def convertFmu2Mo(self, fmuName):  # 20
         >>> convertFmu2Mo("c:/BouncingBall.Fmu")
         """
 
-        fileName = self._requestApi(apiName='importFMU', entity=fmuName)
+        fmu_path = self._session.omcpath(fmu)
+
+        if not fmu_path.is_file():
+            raise ModelicaSystemError(f"Missing FMU file: {fmu_path.as_posix()}")
+
+        filename = self._requestApi(apiName='importFMU', entity=fmu_path.as_posix())
+        filepath = self.getWorkDirectory() / filename
 
         # report proper error message
-        if not os.path.exists(fileName):
-            raise ModelicaSystemError(f"Missing file {fileName}")
+        if not filepath.is_file():
+            raise ModelicaSystemError(f"Missing file {filepath.as_posix()}")
 
-        return fileName
+        self.model(
+            name=f"{fmu_path.stem}_me_FMU",
+            file=filepath,
+        )
+
+        return filepath
 
     def optimize(self) -> dict[str, Any]:
         """Perform model-based optimization.
@@ -1903,15 +1946,17 @@ def __init__(
         """
 
         self._mod = ModelicaSystem(
-            fileName=fileName,
-            modelName=modelName,
-            lmodel=lmodel,
             commandLineOptions=commandLineOptions,
-            variableFilter=variableFilter,
             customBuildDirectory=customBuildDirectory,
             omhome=omhome,
             omc_process=omc_process,
         )
+        self._mod.model(
+            file=fileName,
+            name=modelName,
+            libraries=lmodel,
+            variable_filter=variableFilter,
+        )
 
         self._model_name = modelName
 

tests/test_FMIExport.py

@@ -5,8 +5,11 @@
 
 
 def test_CauerLowPassAnalog():
-    mod = OMPython.ModelicaSystem(modelName="Modelica.Electrical.Analog.Examples.CauerLowPassAnalog",
-                                  lmodel=["Modelica"])
+    mod = OMPython.ModelicaSystem()
+    mod.model(
+        name="Modelica.Electrical.Analog.Examples.CauerLowPassAnalog",
+        libraries=["Modelica"],
+    )
     tmp = pathlib.Path(mod.getWorkDirectory())
     try:
         fmu = mod.convertMo2Fmu(fileNamePrefix="CauerLowPassAnalog")
@@ -16,7 +19,11 @@ def test_CauerLowPassAnalog():
 
 
 def test_DrumBoiler():
-    mod = OMPython.ModelicaSystem(modelName="Modelica.Fluid.Examples.DrumBoiler.DrumBoiler", lmodel=["Modelica"])
+    mod = OMPython.ModelicaSystem()
+    mod.model(
+        name="Modelica.Fluid.Examples.DrumBoiler.DrumBoiler",
+        libraries=["Modelica"],
+    )
     tmp = pathlib.Path(mod.getWorkDirectory())
     try:
         fmu = mod.convertMo2Fmu(fileNamePrefix="DrumBoiler")