Source code for astropy.config.paths

# Licensed under a 3-clause BSD style license - see LICENSE.rst
""" This module contains functions to determine where configuration and
data/cache files used by Astropy should be placed.
"""

from functools import wraps

import os
import shutil
import sys


__all__ = ['get_config_dir', 'get_cache_dir', 'set_temp_config',
           'set_temp_cache']


def _find_home():
    """ Locates and return the home directory (or best approximation) on this
    system.

    Raises
    ------
    OSError
        If the home directory cannot be located - usually means you are running
        Astropy on some obscure platform that doesn't have standard home
        directories.
    """

    # First find the home directory - this is inspired by the scheme ipython
    # uses to identify "home"
    if os.name == 'posix':
        # Linux, Unix, AIX, OS X
        if 'HOME' in os.environ:
            homedir = os.environ['HOME']
        else:
            raise OSError('Could not find unix home directory to search for '
                          'astropy config dir')
    elif os.name == 'nt':  # This is for all modern Windows (NT or after)
        if 'MSYSTEM' in os.environ and os.environ.get('HOME'):
            # Likely using an msys shell; use whatever it is using for its
            # $HOME directory
            homedir = os.environ['HOME']
        # Next try for a network home
        elif 'HOMESHARE' in os.environ:
            homedir = os.environ['HOMESHARE']
        # See if there's a local home
        elif 'HOMEDRIVE' in os.environ and 'HOMEPATH' in os.environ:
            homedir = os.path.join(os.environ['HOMEDRIVE'],
                                   os.environ['HOMEPATH'])
        # Maybe a user profile?
        elif 'USERPROFILE' in os.environ:
            homedir = os.path.join(os.environ['USERPROFILE'])
        else:
            try:
                import winreg as wreg
                shell_folders = r'Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders'
                key = wreg.OpenKey(wreg.HKEY_CURRENT_USER, shell_folders)

                homedir = wreg.QueryValueEx(key, 'Personal')[0]
                key.Close()
            except Exception:
                # As a final possible resort, see if HOME is present
                if 'HOME' in os.environ:
                    homedir = os.environ['HOME']
                else:
                    raise OSError('Could not find windows home directory to '
                                  'search for astropy config dir')
    else:
        # for other platforms, try HOME, although it probably isn't there
        if 'HOME' in os.environ:
            homedir = os.environ['HOME']
        else:
            raise OSError('Could not find a home directory to search for '
                          'astropy config dir - are you on an unspported '
                          'platform?')
    return homedir


[docs]def get_config_dir(create=True): """ Determines the Astropy configuration directory name and creates the directory if it doesn't exist. This directory is typically ``$HOME/.astropy/config``, but if the XDG_CONFIG_HOME environment variable is set and the ``$XDG_CONFIG_HOME/astropy`` directory exists, it will be that directory. If neither exists, the former will be created and symlinked to the latter. Returns ------- configdir : str The absolute path to the configuration directory. """ # symlink will be set to this if the directory is created linkto = None # If using set_temp_config, that overrides all if set_temp_config._temp_path is not None: xch = set_temp_config._temp_path config_path = os.path.join(xch, 'astropy') if not os.path.exists(config_path): os.mkdir(config_path) return os.path.abspath(config_path) # first look for XDG_CONFIG_HOME xch = os.environ.get('XDG_CONFIG_HOME') if xch is not None and os.path.exists(xch): xchpth = os.path.join(xch, 'astropy') if not os.path.islink(xchpth): if os.path.exists(xchpth): return os.path.abspath(xchpth) else: linkto = xchpth return os.path.abspath(_find_or_create_astropy_dir('config', linkto))
[docs]def get_cache_dir(): """ Determines the Astropy cache directory name and creates the directory if it doesn't exist. This directory is typically ``$HOME/.astropy/cache``, but if the XDG_CACHE_HOME environment variable is set and the ``$XDG_CACHE_HOME/astropy`` directory exists, it will be that directory. If neither exists, the former will be created and symlinked to the latter. Returns ------- cachedir : str The absolute path to the cache directory. """ # symlink will be set to this if the directory is created linkto = None # If using set_temp_cache, that overrides all if set_temp_cache._temp_path is not None: xch = set_temp_cache._temp_path cache_path = os.path.join(xch, 'astropy') if not os.path.exists(cache_path): os.mkdir(cache_path) return os.path.abspath(cache_path) # first look for XDG_CACHE_HOME xch = os.environ.get('XDG_CACHE_HOME') if xch is not None and os.path.exists(xch): xchpth = os.path.join(xch, 'astropy') if not os.path.islink(xchpth): if os.path.exists(xchpth): return os.path.abspath(xchpth) else: linkto = xchpth return os.path.abspath(_find_or_create_astropy_dir('cache', linkto))
class _SetTempPath: _temp_path = None _default_path_getter = None def __init__(self, path=None, delete=False): if path is not None: path = os.path.abspath(path) self._path = path self._delete = delete self._prev_path = self.__class__._temp_path def __enter__(self): self.__class__._temp_path = self._path return self._default_path_getter() def __exit__(self, *args): self.__class__._temp_path = self._prev_path if self._delete and self._path is not None: shutil.rmtree(self._path) def __call__(self, func): """Implements use as a decorator.""" @wraps(func) def wrapper(*args, **kwargs): with self: func(*args, **kwargs) return wrapper
[docs]class set_temp_config(_SetTempPath): """ Context manager to set a temporary path for the Astropy config, primarily for use with testing. If the path set by this context manager does not already exist it will be created, if possible. This may also be used as a decorator on a function to set the config path just within that function. Parameters ---------- path : str, optional The directory (which must exist) in which to find the Astropy config files, or create them if they do not already exist. If None, this restores the config path to the user's default config path as returned by `get_config_dir` as though this context manager were not in effect (this is useful for testing). In this case the ``delete`` argument is always ignored. delete : bool, optional If True, cleans up the temporary directory after exiting the temp context (default: False). """ _default_path_getter = staticmethod(get_config_dir) def __enter__(self): # Special case for the config case, where we need to reset all the # cached config objects from .configuration import _cfgobjs path = super().__enter__() _cfgobjs.clear() return path def __exit__(self, *args): from .configuration import _cfgobjs super().__exit__(*args) _cfgobjs.clear()
[docs]class set_temp_cache(_SetTempPath): """ Context manager to set a temporary path for the Astropy download cache, primarily for use with testing (though there may be other applications for setting a different cache directory, for example to switch to a cache dedicated to large files). If the path set by this context manager does not already exist it will be created, if possible. This may also be used as a decorator on a function to set the cache path just within that function. Parameters ---------- path : str The directory (which must exist) in which to find the Astropy cache files, or create them if they do not already exist. If None, this restores the cache path to the user's default cache path as returned by `get_cache_dir` as though this context manager were not in effect (this is useful for testing). In this case the ``delete`` argument is always ignored. delete : bool, optional If True, cleans up the temporary directory after exiting the temp context (default: False). """ _default_path_getter = staticmethod(get_cache_dir)
def _find_or_create_astropy_dir(dirnm, linkto): innerdir = os.path.join(_find_home(), '.astropy') maindir = os.path.join(_find_home(), '.astropy', dirnm) if not os.path.exists(maindir): # first create .astropy dir if needed if not os.path.exists(innerdir): try: os.mkdir(innerdir) except OSError: if not os.path.isdir(innerdir): raise elif not os.path.isdir(innerdir): msg = 'Intended Astropy directory {0} is actually a file.' raise OSError(msg.format(innerdir)) try: os.mkdir(maindir) except OSError: if not os.path.isdir(maindir): raise if (not sys.platform.startswith('win') and linkto is not None and not os.path.exists(linkto)): os.symlink(maindir, linkto) elif not os.path.isdir(maindir): msg = 'Intended Astropy {0} directory {1} is actually a file.' raise OSError(msg.format(dirnm, maindir)) return os.path.abspath(maindir)