Enable use of pathlib.Path objects for paths

CHANGELOG

@@ -4,6 +4,11 @@
     * Fixed a result handling issue for `dynamic_diagnostics = True` and `["<solver>_options"]["clock_step"] = False`.
     * Fixed an issue for the `Master` algorithm where connection values could be initialized incorrectly, when FMUs 
       were initialized separately and using `step_size_downsampling_factor`.
+    * Enabled use of `pathlib.Path` objects for:
+        * Paths when loading FMUs
+        * `log_file_name` when loading FMUs
+        * `pyfmi.common.log.parse_xml_log` & `extract_xml_log`, including `fmu.extract_xml_log()`.
+        * `result_file_name` as simulation option and manual use of `ResultReader` classes
 
 --- PyFMI-2.20.1 ---
     * Resolved issue where caching in result handling was too persistent and could prevent automatic garbage collection.

src/common/io.py

@@ -28,6 +28,7 @@
 from shutil import disk_usage
 import abc
 import warnings
+from pathlib import Path
 
 import numpy as np
 import scipy
@@ -388,7 +389,7 @@ def __init__(self, filename, delimiter=";"):
                 Default: ";""
         """
 
-        if isinstance(filename, str):
+        if isinstance(filename, (str, Path)):
             try:
                 fid = codecs.open(filename,'r','utf-8')
             except FileNotFoundError as e:
@@ -997,7 +998,8 @@ def __init__(self,fname):
                 Name of file or stream object which the result is written to.
                 If fname is a stream, it needs to support 'readline' and 'seek'.
         """
-        if isinstance(fname, str):
+        if isinstance(fname, (str, Path)):
+            fname = os.path.abspath(fname)
             try:
                 fid = codecs.open(fname,'r','utf-8')
             except FileNotFoundError as e:
@@ -1302,8 +1304,8 @@ def __init__(self, fname, delayed_trajectory_loading = True, allow_file_updates=
                 Default: False
         """
 
-        if isinstance(fname, str):
-            self._fname = fname
+        if isinstance(fname, (str, Path)):
+            self._fname = os.path.abspath(fname)
             self._is_stream = False
         elif hasattr(fname, "name") and os.path.isfile(fname.name):
             self._fname = fname.name
@@ -2134,7 +2136,7 @@ def simulation_start(self):
                         cont_alias_bool.append(-1 if var.alias == fmi.FMI_NEGATED_ALIAS else 1)
 
         # Open file
-        if isinstance(self.file_name, str):
+        if isinstance(self.file_name, (str, Path)):
             f = codecs.open(self.file_name,'w','utf-8')
             self.file_open = True
         else:
@@ -2254,7 +2256,7 @@ def file_name(self):
     @cached_property
     def _is_stream(self):
         file = self.file_name
-        if isinstance(file, str):
+        if isinstance(file, (str, Path)):
             return False
         else:
             if not (hasattr(file, 'write') and hasattr(file, 'seek')):
@@ -2899,7 +2901,7 @@ def simulation_start(self, diagnostics_params={}, diagnostics_vars={}):
 
         # Open file
         file_name = self.file_name
-        if isinstance(self.file_name, str):
+        if isinstance(self.file_name, (str, Path)):
             self._file = open(file_name,'wb')
         else:
             if not (hasattr(self.file_name, 'write') and hasattr(self.file_name, 'seek') and (hasattr(self.file_name, 'tell'))):
@@ -3177,7 +3179,7 @@ def __init__(self, fname):
                 which the result is written to.
         """
 
-        if isinstance(fname, str):
+        if isinstance(fname, (str, Path)):
             self._fname = fname
         elif hasattr(fname, "name") and os.path.isfile(fname.name):
             self._fname = fname.name

src/common/log/parser.py

@@ -24,6 +24,7 @@
 from distutils.util import strtobool
 from pyfmi.common.log.tree import Node, Comment
 from pyfmi.exceptions import FMUException
+from pathlib import Path
 
 ## Leaf parser ##
 
@@ -217,12 +218,12 @@ def extract_xml_log(dest, log, modulename = 'Model', max_size = None):
                 Default: None
     """
     # if it is a string, we assume we write to a file (since the file doesn't exist yet)
-    dest_is_file = isinstance(dest, str)
+    dest_is_file = isinstance(dest, (str, Path))
     if not dest_is_file:
         if not hasattr(dest, 'write'):
             raise FMUException("If input argument 'dest' is a stream it needs to support the attribute 'write'.")
 
-    if isinstance(log, str):
+    if isinstance(log, (str, Path)):
         with open(log, 'r') as sourcefile:
             if dest_is_file:
                 with open(dest, 'w') as destfile:

src/pyfmi/fmi.pyx

@@ -26,6 +26,8 @@ For profiling:
 """
 import os
 cimport cython
+from pathlib import Path
+from typing import Union
 
 cimport pyfmi.fmil_import as FMIL
 
@@ -177,15 +179,15 @@ from pyfmi.fmi3 import (
 cdef void importlogger_load_fmu(FMIL.jm_callbacks* c, FMIL.jm_string module, FMIL.jm_log_level_enu_t log_level, FMIL.jm_string message):
     (<list>c.context).append("FMIL: module = %s, log level = %d: %s"%(module, log_level, message))
 
-cpdef load_fmu(fmu, log_file_name = "", kind = 'auto',
+cpdef load_fmu(fmu: Union[str, Path], log_file_name = None, kind = 'auto',
                log_level = FMI_DEFAULT_LOG_LEVEL, allow_unzipped_fmu = False):
     """
     Helper method for creating a model instance.
 
     Parameters::
 
         fmu --
-            Name of the fmu as a string.
+            Path to the fmu.
 
         log_file_name --
             Filename for file used to save log messages.
@@ -194,7 +196,7 @@ cpdef load_fmu(fmu, log_file_name = "", kind = 'auto',
             for asyncio-streams, then this needs to be implemented on the user-side, there is no additional methods invoked
             on the stream instance after 'write' has been invoked on the PyFMI side.
             The stream must also be open and writable during the entire time.
-            Default: "" (Generates automatically)
+            Default: None = Generates automatically as <model_identifier>_log.txt
 
         kind --
             String indicating the kind of model to create. This is only
@@ -266,9 +268,9 @@ cpdef load_fmu(fmu, log_file_name = "", kind = 'auto',
     context = FMIL.fmi_import_allocate_context(&callbacks)
 
     # Get the FMI version of the provided model
-    fmu_temp_dir = pyfmi_util.encode(fmu) if allow_unzipped_fmu else pyfmi_util.encode(create_temp_dir())
-    fmu_full_path = pyfmi_util.encode(fmu_full_path)
-    version = FMI_BASE.import_and_get_version(context, fmu_full_path, fmu_temp_dir, allow_unzipped_fmu)
+    fmu_temp_dir = pyfmi_util.encode(fmu_full_path) if allow_unzipped_fmu else pyfmi_util.encode(create_temp_dir())
+    fmu_full_path_encoded = pyfmi_util.encode(fmu_full_path)
+    version = FMI_BASE.import_and_get_version(context, fmu_full_path_encoded, fmu_temp_dir, allow_unzipped_fmu)
 
     # Check the version & parse XML
     if version == FMIL.fmi_version_1_enu:

src/pyfmi/fmi1.pyx

@@ -20,6 +20,8 @@
 import os
 import logging
 cimport cython
+from pathlib import Path
+from typing import Union
 
 import numpy as np
 cimport numpy as np
@@ -230,15 +232,15 @@ cdef class FMUModelBase(FMI_BASE.ModelBase):
     """
     An FMI Model loaded from a DLL.
     """
-    def __init__(self, fmu, log_file_name="", log_level=FMI_DEFAULT_LOG_LEVEL,
+    def __init__(self, fmu: Union[str, Path], log_file_name=None, log_level=FMI_DEFAULT_LOG_LEVEL,
                  _unzipped_dir=None, _connect_dll=True, allow_unzipped_fmu = False):
         """
         Constructor of the model.
 
         Parameters::
 
             fmu --
-                Name of the fmu as a string.
+                Path to the FMU.
 
             log_file_name --
                 Filename for file used to save logmessages.
@@ -247,7 +249,7 @@ cdef class FMUModelBase(FMI_BASE.ModelBase):
                 for asyncio-streams, then this needs to be implemented on the user-side, there is no additional methods invoked
                 on the stream instance after 'write' has been invoked on the PyFMI side.
                 The stream must also be open and writable during the entire time.
-                Default: "" (Generates automatically)
+                Default: None = Generates automatically as <model_identifier>_log.txt
 
             log_level --
                 Determines the logging output. Can be set between 0
@@ -297,7 +299,8 @@ cdef class FMUModelBase(FMI_BASE.ModelBase):
         self._setup_log_state(log_level)
         self._loaded_with_log_level = log_level
 
-        self._fmu_full_path = os.path.abspath(fmu)
+        fmu = os.path.abspath(fmu)
+        self._fmu_full_path = fmu
         if _unzipped_dir:
             fmu_temp_dir = pyfmi_util.encode(_unzipped_dir)
         elif self._allow_unzipped_fmu:
@@ -389,7 +392,10 @@ cdef class FMUModelBase(FMI_BASE.ModelBase):
         self._nContinuousStates = FMIL1.fmi1_import_get_number_of_continuous_states(self._fmu)
         self._log_handler.capi_end_callback(self._max_log_size_msg_sent, self._current_log_size)
 
-        if not isinstance(log_file_name, str):
+        if log_file_name is None:
+            log_file_name = self._get_default_log_file_name()
+
+        if not isinstance(log_file_name, (str, Path)):
             self._set_log_stream(log_file_name)
             for i in range(len(self._log)):
                 try:
@@ -400,7 +406,8 @@ cdef class FMUModelBase(FMI_BASE.ModelBase):
                     else:
                         logging.warning("Unable to log to stream.")
         else:
-            fmu_log_name = pyfmi_util.encode((self._modelId + "_log.txt") if log_file_name=="" else log_file_name)
+            log_file_name = str(log_file_name) # convert e.g. pathlib.Path objects
+            fmu_log_name = pyfmi_util.encode(log_file_name)
             self._fmu_log_name = <char*>FMIL.malloc((FMIL.strlen(fmu_log_name)+1)*sizeof(char))
             FMIL.strcpy(self._fmu_log_name, fmu_log_name)
 
@@ -1713,7 +1720,7 @@ cdef class FMUModelCS1(FMUModelBase):
     #First step only support fmi1_fmu_kind_enu_cs_standalone
     #stepFinished not supported
 
-    def __init__(self, fmu, log_file_name="", log_level=FMI_DEFAULT_LOG_LEVEL,
+    def __init__(self, fmu: Union[str, Path], log_file_name=None, log_level=FMI_DEFAULT_LOG_LEVEL,
                  _unzipped_dir=None, _connect_dll=True, allow_unzipped_fmu = False):
         #Call super
         FMUModelBase.__init__(self,fmu,log_file_name, log_level, _unzipped_dir, _connect_dll, allow_unzipped_fmu)
@@ -2255,7 +2262,7 @@ cdef class FMUModelME1(FMUModelBase):
     An FMI Model loaded from a DLL.
     """
 
-    def __init__(self, fmu, log_file_name="", log_level=FMI_DEFAULT_LOG_LEVEL,
+    def __init__(self, fmu: Union[str, Path], log_file_name=None, log_level=FMI_DEFAULT_LOG_LEVEL,
                  _unzipped_dir=None, _connect_dll=True, allow_unzipped_fmu = False):
         #Call super
         FMUModelBase.__init__(self,fmu,log_file_name, log_level, _unzipped_dir, _connect_dll, allow_unzipped_fmu)
@@ -2980,7 +2987,7 @@ cdef class FMUModelME1(FMUModelBase):
             self._instantiated_fmu = 0
 
 cdef object _load_fmi1_fmu(
-    fmu, 
+    fmu: Union[str, Path], 
     object log_file_name, 
     str kind, 
     int log_level, 

src/pyfmi/fmi2.pyx

@@ -20,6 +20,8 @@
 import os
 import logging
 cimport cython
+from pathlib import Path
+from typing import Union
 
 import numpy as np
 cimport numpy as np
@@ -460,15 +462,15 @@ cdef class FMUModelBase2(FMI_BASE.ModelBase):
     """
     FMI Model loaded from a dll.
     """
-    def __init__(self, fmu, log_file_name="", log_level=FMI_DEFAULT_LOG_LEVEL,
+    def __init__(self, fmu: Union[str, Path], log_file_name=None, log_level=FMI_DEFAULT_LOG_LEVEL,
                  _unzipped_dir=None, _connect_dll=True, allow_unzipped_fmu = False):
         """
         Constructor of the model.
 
         Parameters::
 
             fmu --
-                Name of the fmu as a string.
+                Path to the FMU.
 
             log_file_name --
                 Filename for file used to save logmessages.
@@ -477,7 +479,7 @@ cdef class FMUModelBase2(FMI_BASE.ModelBase):
                 for asyncio-streams, then this needs to be implemented on the user-side, there is no additional methods invoked
                 on the stream instance after 'write' has been invoked on the PyFMI side.
                 The stream must also be open and writable during the entire time.
-                Default: "" (Generates automatically)
+                Default: None = Generates automatically as <model_identifier>_log.txt
 
             log_level --
                 Determines the logging output. Can be set between 0
@@ -558,7 +560,8 @@ cdef class FMUModelBase2(FMI_BASE.ModelBase):
         self._setup_log_state(log_level)
         self._loaded_with_log_level = log_level
 
-        self._fmu_full_path = pyfmi_util.encode(os.path.abspath(fmu))
+        fmu = os.path.abspath(fmu)
+        self._fmu_full_path = pyfmi_util.encode(fmu)
         check_fmu_args(self._allow_unzipped_fmu, fmu, self._fmu_full_path)
 
         # Create a struct for allocation
@@ -659,12 +662,15 @@ cdef class FMUModelBase2(FMI_BASE.ModelBase):
         self._nContinuousStates = FMIL2.fmi2_import_get_number_of_continuous_states(self._fmu)
         self._log_handler.capi_end_callback(self._max_log_size_msg_sent, self._current_log_size)
 
-        if not isinstance(log_file_name, str):
+        if log_file_name is None:
+            log_file_name = self._get_default_log_file_name()
+        if not isinstance(log_file_name, (str, Path)):
             self._set_log_stream(log_file_name)
             for i in range(len(self._log)):
                 self._log_stream.write("FMIL: module = %s, log level = %d: %s\n"%(self._log[i][0], self._log[i][1], self._log[i][2]))
         else:
-            fmu_log_name = pyfmi_util.encode((self._modelId + "_log.txt") if log_file_name=="" else log_file_name)
+            log_file_name = str(log_file_name) # convert e.g. pathlib.Path objects
+            fmu_log_name = pyfmi_util.encode(log_file_name)
             self._fmu_log_name = <char*>FMIL.malloc((FMIL.strlen(fmu_log_name)+1)*sizeof(char))
             FMIL.strcpy(self._fmu_log_name, fmu_log_name)
 
@@ -3564,15 +3570,15 @@ cdef class FMUModelCS2(FMUModelBase2):
     """
     Co-simulation model loaded from a dll
     """
-    def __init__(self, fmu, log_file_name = "", log_level=FMI_DEFAULT_LOG_LEVEL,
+    def __init__(self, fmu: Union[str, Path], log_file_name = None, log_level=FMI_DEFAULT_LOG_LEVEL,
                  _unzipped_dir=None, _connect_dll=True, allow_unzipped_fmu = False):
         """
         Constructor of the model.
 
         Parameters::
 
             fmu --
-                Name of the fmu as a string.
+                Path to the FMU.
 
             log_file_name --
                 Filename for file used to save logmessages.
@@ -3581,7 +3587,7 @@ cdef class FMUModelCS2(FMUModelBase2):
                 for asyncio-streams, then this needs to be implemented on the user-side, there is no additional methods invoked
                 on the stream instance after 'write' has been invoked on the PyFMI side.
                 The stream must also be open and writable during the entire time.
-                Default: "" (Generates automatically)
+                Default: None = Generates automatically as <model_identifier>_log.txt
 
             log_level --
                 Determines the logging output. Can be set between 0
@@ -4195,15 +4201,15 @@ cdef class FMUModelME2(FMUModelBase2):
     Model-exchange model loaded from a dll
     """
 
-    def __init__(self, fmu, log_file_name = "", log_level=FMI_DEFAULT_LOG_LEVEL,
+    def __init__(self, fmu: Union[str, Path], log_file_name = None, log_level=FMI_DEFAULT_LOG_LEVEL,
                  _unzipped_dir=None, _connect_dll=True, allow_unzipped_fmu = False):
         """
         Constructor of the model.
 
         Parameters::
 
             fmu --
-                Name of the fmu as a string.
+                Path to the FMU.
 
             log_file_name --
                 Filename for file used to save logmessages.
@@ -4212,7 +4218,7 @@ cdef class FMUModelME2(FMUModelBase2):
                 for asyncio-streams, then this needs to be implemented on the user-side, there is no additional methods invoked
                 on the stream instance after 'write' has been invoked on the PyFMI side.
                 The stream must also be open and writable during the entire time.
-                Default: "" (Generates automatically)
+                Default: None = Generates automatically as <model_identifier>_log.txt
 
             log_level --
                 Determines the logging output. Can be set between 0
@@ -5178,7 +5184,7 @@ cdef class WorkerClass2:
         return ret
 
 cdef object _load_fmi2_fmu(
-    fmu,
+    fmu: Union[str, Path],
     object log_file_name,
     str kind,
     int log_level,