how to concisely create a temporary file that is a copy of another file in python

Question

I know that it is possible to create a temporary file, and write the data of the file I wish to copy to it. I was just wondering if there was a function like:

Answer 1

This isn't quite as concise, and I imagine there may be issues with exception safety, (e.g. what happens if 'original_path' doesn't exist, or the temporary_copy object goes out of scope while you have the file open) but this code adds a little RAII to the clean up. The difference here to using NamedTemporaryFile directly is that rather than ending up with a file object, you end up with a file, which is occasionally desirable (e.g. if you plan to call out to other code to read it, or some such.)

import os,shutil,tempfile
class temporary_copy(object):

    def __init__(self,original_path):
        self.original_path = original_path

    def __enter__(self):
        temp_dir = tempfile.gettempdir()
        base_path = os.path.basename(self.original_path)
        self.path = os.path.join(temp_dir,base_path)
        shutil.copy2(self.original_path, self.path)
        return self.path

    def __exit__(self,exc_type, exc_val, exc_tb):
        os.remove(self.path)

in your code you'd write:

with temporary_copy(path) as temporary_path_to_copy:
    ... do stuff with temporary_path_to_copy ...

# Here in the code, the copy should now have been deleted.