"""This module contains helper functions for working with temp and cache directories."""
# Copyright (C) 2008 Martin Sandve Alnes
# Copyright (C) 2012 Florian Rathgeber
#
# This file is part of Instant.
#
# Instant is free software: you can redistribute it and/or modify
# it under the terms of the GNU Lesser General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# Instant is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public License
# along with Instant. If not, see <http://www.gnu.org/licenses/>.
#
# Alternatively, Instant may be distributed under the terms of the BSD license.
# Utilities for directory handling:
from six import string_types
import os
import sys
import errno
import shutil
import tempfile
import time
from .signatures import compute_checksum
from .output import instant_debug, instant_assert
_tmp_dir = None
[docs]def get_temp_dir():
"""Return a temporary directory for the duration of this process.
Multiple calls in the same process returns the same directory.
Remember to call delete_temp_dir() before exiting."""
global _tmp_dir
if _tmp_dir is None:
datestring = "%d-%d-%d-%02d-%02d" % time.localtime()[:5]
suffix = datestring + "_instant_" + compute_checksum(get_default_cache_dir())
_tmp_dir = tempfile.mkdtemp(suffix)
instant_debug("Created temp directory '%s'." % _tmp_dir)
return _tmp_dir
[docs]def delete_temp_dir():
"""Delete the temporary directory created by get_temp_dir()."""
global _tmp_dir
if _tmp_dir and os.path.isdir(_tmp_dir):
shutil.rmtree(_tmp_dir, ignore_errors=True)
_tmp_dir = None
[docs]def get_instant_dir():
"Return the default instant directory, creating it if necessary."
# Place default cache dir in virtualenv or conda prefix
# if one of them are active, or under user's home directory
home = os.path.expanduser("~")
venv = os.environ.get("VIRTUAL_ENV")
cenv = os.environ.get("CONDA_PREFIX")
if venv == sys.prefix:
env = venv
elif cenv == sys.prefix:
env = cenv
else:
env = home
instant_dir = os.path.join(env, ".cache", "instant")
# If placed in home directory, add python version for safety,
# since C extensions are not compatible across versions.
# (for python 3, it's possible to use the stable C API,
# however we don't know if the instant user has done that)
if env == home:
ver = "python%d.%d" % sys.version_info[:2]
instant_dir = os.path.join(instant_dir, ver)
makedirs(instant_dir)
return instant_dir
[docs]def get_default_cache_dir():
"Return the default cache directory."
cache_dir = os.environ.get("INSTANT_CACHE_DIR")
# Catches the cases where INSTANT_CACHE_DIR is not set or ''
if not cache_dir:
cache_dir = os.path.join(get_instant_dir(), "cache")
makedirs(cache_dir)
return cache_dir
[docs]def get_default_error_dir():
"Return the default error directory."
error_dir = os.environ.get("INSTANT_ERROR_DIR")
# Catches the cases where INSTANT_ERROR_DIR is not set or ''
if not error_dir:
error_dir = os.path.join(get_instant_dir(), "error")
makedirs(error_dir)
return error_dir
[docs]def validate_cache_dir(cache_dir):
if cache_dir is None:
return get_default_cache_dir()
instant_assert(isinstance(cache_dir, string_types), "Expecting cache_dir to be a string.")
cache_dir = os.path.abspath(cache_dir)
makedirs(cache_dir)
return cache_dir
[docs]def makedirs(path):
"""
Creates a directory (tree). If directory already excists it does nothing.
"""
try:
os.makedirs(path)
instant_debug("In instant.makedirs: Creating directory %r" % path)
except os.error as e:
if e.errno != errno.EEXIST:
raise
def _test():
from .output import set_logging_level
set_logging_level("DEBUG")
print("Temp dir:", get_temp_dir())
print("Instant dir:", get_instant_dir())
print("Default cache dir:", get_default_cache_dir())
print("Default error dir:", get_default_error_dir())
delete_temp_dir()
if __name__ == "__main__":
_test()