app/django/utils/_os.py
author Todd Larsen <tlarsen@google.com>
Thu, 28 Aug 2008 23:54:35 +0000
changeset 119 50d8d58dcd7c
parent 54 03e267d67478
child 323 ff1a9aa48cfd
permissions -rw-r--r--
Add soc.views.simple containing (initially) two simple template views. templateWithLinkName() is a view that can replace most public() read-only views. errorResponse() is a view that renders an error page for out_of_band.ErrorResponse exceptions. Also, change response_helpers.respond() to accept keyword arguments to pass to http.HttpResponse(). (errorResponse() makes use of this new respond() feature.) Patch by: Todd Larsen Review by: to-be-reviewed

from os.path import join, normcase, abspath, sep

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).
    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