# (C) Copyright 2005-2022 Enthought, Inc., Austin, TX # All rights reserved. # # This software is provided without warranty under the terms of the BSD # license included in LICENSE.txt and may be redistributed only under # the conditions described in the aforementioned license. The license # is also available online at http://www.enthought.com/licenses/BSD.txt # # Thanks for using Enthought open source! """ Enthought Tool Suite configuration information. """ # Standard library imports. import contextlib import os import sys class ETSToolkitError(RuntimeError): """ Error raised by issues importing ETS toolkits Attributes ---------- message : str The message detailing the error. toolkit : str or None The toolkit associated with the error. """ def __init__(self, message="", toolkit=None, *args): if not message and toolkit: message = "could not import toolkit '{0}'".format(toolkit) self.toolkit = toolkit self.message = message if message: if toolkit: args = (toolkit,) + args args = (message,) + args self.args = args class ETSConfigType: """ Enthought Tool Suite configuration information. Instances of this class record state useful for ETS-using applications, including the current GUI toolkit in use, and data and home directory setttings. Users typically shouldn't make use of this class directly. Instead, use the module-level :data:`~.ETSConfig` instance of this class, which is shared between the various ETS packages. """ # This class should not use ANY other package in the tool suite so that it # will always work no matter which other packages are present. ########################################################################### # 'object' interface. ########################################################################### #### operator methods ##################################################### def __init__(self): # Note that this constructor can only ever be called from within this # module, since we don't expose the class. # Shadow attributes for properties. self._application_data = None self._application_home = None self._company = None self._toolkit = None self._kiva_backend = None self._user_data = None ########################################################################### # 'ETSConfig' interface. ########################################################################### #### properties ########################################################### def get_application_data(self, create=False): """ Return the application data directory path. Parameters ---------- create: bool Create the corresponding directory or not. Notes ----- - This is a directory that applications and packages can safely write non-user accessible data to i.e. configuration information, preferences etc. - Do not put anything in here that the user might want to navigate to e.g. projects, user data files etc. - The actual location differs between operating systems. """ if self._application_data is None: self._application_data = self._initialize_application_data( create=create ) return self._application_data @property def application_data(self): """ Property getter, see get_application_data's docstring. """ return self.get_application_data(create=True) @application_data.setter def application_data(self, application_data): """ Property setter. """ self._application_data = application_data @application_data.deleter def application_data(self): self._application_data = None def get_application_home(self, create=False): """ Return the application home directory path. Parameters ---------- create: bool Create the corresponding directory or not. Note ---- - This is a directory named after the current, running application that imported this module that applications and packages can safely write non-user accessible data to i.e. configuration information, preferences etc. It is a sub-directory of self.application_data, named after the directory that contains the "main" python script that started the process. For example, if application foo is started with a script named "run.py" in a directory named "foo", then the application home would be: /foo, regardless of if it was launched with "python /run.py" or "cd ; python run.py" - This is useful for library modules used in apps that need to store state, preferences, etc. for the specific app only, and not for all apps which use that library module. If the library module uses ETSConfig.application_home, they can store prefs for the app all in one place and do not need to know the details of where each app might reside. - Do not put anything in here that the user might want to navigate to e.g. projects, user home files etc. - The actual location differs between operating systems. """ if self._application_home is None: self._application_home = os.path.join( self.get_application_data(create=create), self._get_application_dirname(), ) return self._application_home @property def application_home(self): """ Property getter, see get_application_home's docstring. """ return self.get_application_home(create=True) @application_home.setter def application_home(self, application_home): """ Property setter. """ self._application_home = application_home @application_home.deleter def application_home(self): self._application_home = None @property def company(self): """ Property getter. """ if self._company is None: self._company = self._initialize_company() return self._company @company.setter def company(self, company): """ Property setter for the company name. """ self._company = company @company.deleter def company(self): self._company = None @contextlib.contextmanager def provisional_toolkit(self, toolkit): """ Perform an operation with toolkit provisionally set This sets the toolkit attribute of the ETSConfig object to the provided value. If the operation fails with an exception, the toolkit is reset to nothing. This method should only be called if the toolkit is not currently set. Parameters ---------- toolkit : string The name of the toolkit to provisionally use. Raises ------ ETSToolkitError If the toolkit attribute is already set, then an ETSToolkitError will be raised when entering the context manager. """ if self.toolkit: msg = "ETSConfig toolkit is already set to '{0}'" raise ETSToolkitError(msg.format(self.toolkit)) self.toolkit = toolkit try: yield except: # reset the toolkit state self._toolkit = "" raise @property def toolkit(self): """ Property getter for the GUI toolkit. The value returned is, in order of preference: the value set by the application; the value specified by the 'ETS_TOOLKIT' environment variable; otherwise the empty string. """ if self._toolkit is None: self._toolkit = self._initialize_toolkit() return self._toolkit.split(".")[0] @toolkit.setter def toolkit(self, toolkit): """ Property setter for the GUI toolkit. The toolkit can be set more than once, but only if it is the same one each time. An application that is written for a particular toolkit can explicitly set it before any other module that gets the value is imported. """ if self._toolkit and self._toolkit != toolkit: raise ValueError( "cannot set toolkit to %s because it has " "already been set to %s" % (toolkit, self._toolkit) ) self._toolkit = toolkit @toolkit.deleter def toolkit(self): self._toolkit = None @property def enable_toolkit(self): """ Deprecated: This property is no longer used. Property getter for the Enable backend. The value returned is, in order of preference: the value set by the application; the value specified by the 'ENABLE_TOOLKIT' environment variable; otherwise the empty string. """ from warnings import warn warn("Use of the enable_toolkit attribute is deprecated.") return self.toolkit @enable_toolkit.setter def enable_toolkit(self, toolkit): """ Deprecated. Property setter for the Enable toolkit. The toolkit can be set more than once, but only if it is the same one each time. An application that is written for a particular toolkit can explicitly set it before any other module that gets the value is imported. """ from warnings import warn warn("Use of the enable_toolkit attribute is deprecated.") @property def kiva_backend(self): """ Property getter for the Kiva backend. The value returned is dependent on the value of the toolkit property. If toolkit specifies a kiva backend using the extended syntax: [.] then the value of the property will be whatever was specified. Otherwise the value will be a reasonable default for the given enable backend. """ if self._toolkit is None: raise AttributeError( "The kiva_backend attribute is dependent on toolkit, " "which has not been set." ) if "." in self._toolkit: return self._toolkit.split(".")[1] elif self.toolkit == "wx" and sys.platform == "darwin": return "quartz" else: return "image" @property def user_data(self): """ Property getter. This is a directory that users can safely write user accessible data to i.e. user-defined functions, edited functions, etc. The actual location differs between operating systems. """ if self._user_data is None: self._user_data = self._initialize_user_data() return self._user_data @user_data.setter def user_data(self, user_data): """ Property setter. """ self._user_data = user_data @user_data.deleter def user_data(self): self._user_data = None #### private methods ##################################################### # fixme: In future, these methods could allow the properties to be set # via the (as yet non-existent) preference/configuration mechanism. This # would allow configuration via (in order of precedence):- # # - a configuration file # - environment variables # - the command line def _get_application_dirname(self): """ Return the name of the directory (not a path) that the "main" Python script which started this process resides in, or "" if it could not be determined or is not appropriate. For example, if the script that started the current process was named "run.py" in a directory named "foo", and was launched with "python run.py", the name "foo" would be returned (this assumes the directory name is the name of the app, which seems to be as good of an assumption as any). """ dirname = "" main_mod = sys.modules.get("__main__", None) if main_mod is not None: if hasattr(main_mod, "__file__"): main_mod_file = os.path.abspath(main_mod.__file__) dirname = os.path.basename(os.path.dirname(main_mod_file)) return dirname def _initialize_application_data(self, create=True): """ Initializes the (default) application data directory. """ if sys.platform == "win32": environment_variable = "APPDATA" directory_name = self.company else: environment_variable = "HOME" directory_name = "." + self.company.lower() # Lookup the environment variable. parent_directory = os.environ.get(environment_variable, None) if parent_directory is None or parent_directory == "/root": import tempfile from warnings import warn parent_directory = tempfile.gettempdir() user = os.environ.get("USER", None) if user is not None: directory_name += "_%s" % user warn( 'Environment variable "%s" not set, ' 'setting home directory to %s' % (environment_variable, parent_directory) ) application_data = os.path.join(parent_directory, directory_name) if create: # If a file already exists with this name then make sure that it is # a directory! if os.path.exists(application_data): if not os.path.isdir(application_data): raise ValueError( 'File "%s" already exists' % application_data ) # Otherwise, create the directory. else: os.makedirs(application_data) return application_data def _initialize_company(self): """ Initializes the (default) company. """ return "Enthought" def _initialize_toolkit(self): """ Initializes the toolkit. """ if self._toolkit is not None: toolkit = self._toolkit else: toolkit = os.environ.get("ETS_TOOLKIT", "") return toolkit def _initialize_user_data(self): """ Initializes the (default) user data directory. """ # We check what the os.path.expanduser returns parent_directory = os.path.expanduser("~") directory_name = self.company if sys.platform == "win32": try: from win32com.shell import shell, shellcon # Due to the fact that the user's My Documents directory can # be in some pretty strange places, it's safest to just ask # Windows where it is. MY_DOCS = shellcon.CSIDL_PERSONAL parent_directory = shell.SHGetFolderPath(0, MY_DOCS, 0, 0) except ImportError: # But if they don't have pywin32 installed, just do it the # naive way... # Check if the usr_dir is C:\\John Doe\\Documents and Settings. # If yes, then we should modify the usr_dir to be # 'My Documents'. If no, then the user must have modified the # os.environ variables and the directory chosen is a desirable # one. desired_dir = os.path.join(parent_directory, "My Documents") if os.path.exists(desired_dir): parent_directory = desired_dir else: directory_name = directory_name.lower() # The final directory. usr_dir = os.path.join(parent_directory, directory_name) # If a file already exists with this name then make sure that it is # a directory! if os.path.exists(usr_dir): if not os.path.isdir(usr_dir): raise ValueError('File "%s" already exists' % usr_dir) # Otherwise, create the directory. else: os.makedirs(usr_dir) return usr_dir #: This single instance of :class:`~.ETSConfigType` is shared between the #: various ETS packages, and used to store global state relevant to #: ETS-using applications. #: #: See https://github.com/enthought/traits/discussions/1666 for a discussion #: of writing tests that depend on :data:`~.ETSConfig` state. ETSConfig = ETSConfigType()