Source code for monty.tempfile

Temporary directory and file creation utilities.

from __future__ import absolute_import
import os
import tempfile
import shutil

    from pathlib import Path
except ImportError:
        from pathlib2 import Path
    except ImportError:
        Path = None

from monty.shutil import copy_r

__author__ = "Shyue Ping Ong"
__copyright__ = "Copyright 2012, The Materials Project"
__version__ = "0.1"
__maintainer__ = "Shyue Ping Ong"
__email__ = ""
__date__ = "3/6/14"

[docs]class ScratchDir(object): """ .. note:: With effect from Python 3.2, tempfile.TemporaryDirectory already implements much of the functionality of ScratchDir. However, it does not provide options for copying of files to and from (though it is possible to do this with other methods provided by shutil). Creates a "with" context manager that automatically handles creation of temporary directories (utilizing Python's build in temp directory functions) and cleanup when done. This improves on Python's built in functions by allowing for truly temporary workspace that are deleted when it is done. The way it works is as follows: 1. Create a temp dir in specified root path. 2. Optionally copy input files from current directory to temp dir. 3. Change to temp dir. 4. User performs specified operations. 5. Optionally copy generated output files back to original directory. 6. Change back to original directory. 7. Delete temp dir. """ SCR_LINK = "scratch_link" def __init__(self, rootpath, create_symbolic_link=False, copy_from_current_on_enter=False, copy_to_current_on_exit=False): """ Initializes scratch directory given a **root** path. There is no need to try to create unique directory names. The code will generate a temporary sub directory in the rootpath. The way to use this is using a with context manager. Example:: with ScratchDir("/scratch"): do_something() If the root path does not exist or is None, this will function as a simple pass through, i.e., nothing happens. Args: rootpath (str/Path): The path in which to create temp subdirectories. If this is None, no temp directories will be created and this will just be a simple pass through. create_symbolic_link (bool): Whether to create a symbolic link in the current working directory to the scratch directory created. copy_from_current_on_enter (bool): Whether to copy all files from the current directory (recursively) to the temp dir at the start, e.g., if input files are needed for performing some actions. Defaults to False. copy_to_current_on_exit (bool): Whether to copy files from the scratch to the current directory (recursively) at the end. E .g., if output files are generated during the operation. Defaults to False. """ if Path is not None and isinstance(rootpath, Path): rootpath = str(rootpath) self.rootpath = os.path.abspath(rootpath) if rootpath is not None \ else None self.cwd = os.getcwd() self.create_symbolic_link = create_symbolic_link self.start_copy = copy_from_current_on_enter self.end_copy = copy_to_current_on_exit def __enter__(self): tempdir = self.cwd if self.rootpath is not None and os.path.exists(self.rootpath): tempdir = tempfile.mkdtemp(dir=self.rootpath) self.tempdir = os.path.abspath(tempdir) if self.start_copy: copy_r(".", tempdir) if self.create_symbolic_link: os.symlink(tempdir, ScratchDir.SCR_LINK) os.chdir(tempdir) return tempdir def __exit__(self, exc_type, exc_val, exc_tb): if self.rootpath is not None and os.path.exists(self.rootpath): if self.end_copy: tempdir = tempfile.mkdtemp(dir=self.cwd) copy_r(self.cwd, tempdir) for f in os.listdir(self.cwd): fpath = os.path.join(self.cwd, f) try: if f != os.path.basename(tempdir): if os.path.isfile(fpath): os.remove(fpath) else: shutil.rmtree(fpath) except: # Ignore file not found. pass copy_r(".", self.cwd) shutil.rmtree(tempdir) shutil.rmtree(self.tempdir) os.chdir(self.cwd) if self.create_symbolic_link: os.remove(ScratchDir.SCR_LINK)