app/django/utils/_os.py
author Daniel Bentley <dbentley@google.com>
Wed, 15 Apr 2009 08:01:17 +0000
changeset 2184 a1bda9afa5d0
parent 323 ff1a9aa48cfd
permissions -rw-r--r--
Step 2 of moving to new seeding model. Create Seeder class, which abstracts some seeding. Move user to Seeder class, and make new OrganizationSeeder class. If people like this, I'll finish the rest soon. Patch by: Dan Bentley

from os.path import join, normcase, abspath, sep
from django.utils.encoding import force_unicode

def safe_join(base, *paths):
    """
    Joins one or more path components to the base path component intelligently.
    Returns a normalized, absolute version of the final path.

    The final path must be located inside of the base path component (otherwise
    a ValueError is raised).
    """
    # We need to use normcase to ensure we don't false-negative on case
    # insensitive operating systems (like Windows).
    base = force_unicode(base)
    paths = [force_unicode(p) for p in paths]
    final_path = normcase(abspath(join(base, *paths)))
    base_path = normcase(abspath(base))
    base_path_len = len(base_path)
    # Ensure final_path starts with base_path and that the next character after
    # the final path is os.sep (or nothing, in which case final_path must be
    # equal to base_path).
    if not final_path.startswith(base_path) \
       or final_path[base_path_len:base_path_len+1] not in ('', sep):
        raise ValueError('the joined path is located outside of the base path'
                         ' component')
    return final_path