1 #!/usr/bin/python2.5

     2 #

     3 # Copyright 2008 the Melange authors.

     4 #

     5 # Licensed under the Apache License, Version 2.0 (the "License");

     6 # you may not use this file except in compliance with the License.

     7 # You may obtain a copy of the License at

     8 #

     9 #   http://www.apache.org/licenses/LICENSE-2.0

    10 #

    11 # Unless required by applicable law or agreed to in writing, software

    12 # distributed under the License is distributed on an "AS IS" BASIS,

    13 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

    14 # See the License for the specific language governing permissions and

    15 # limitations under the License.

    16 

    17 """Path and link ID manipulation functions.

    18 """

    19 

    20 __authors__ = [

    21   '"Todd Larsen" <tlarsen@google.com>',

    22   '"Lennard de Rijk" <ljvderijk@gmail.com>',

    23   ]

    24 

    25 

    26 from soc.models import linkable

    27 

    28 

    29 def getPartsFromPath(path):

    30   """Splits path string into scope_path and link_id.

    31   

    32   Returns:

    33     {'scope_path': 'everything/but',

    34      'link_id': 'link_id'}

    35     or {} (empty dict) if string did not match PATH_LINK_ID_PATTERN.

    36   """

    37   path_link_name_match = linkable.PATH_LINK_ID_REGEX.match(path)

    38   

    39   if not path_link_name_match:

    40     return {}

    41 

    42   return path_link_name_match.groupdict()

    43 

    44 

    45 def combinePath(path_parts):

    46   """Returns path components combined into a single string.

    47   

    48   Args:

    49     path_parts: a single path string, or a list of path part strings,

    50       or a nested list of path part strings (where the zeroeth element in

    51       the list is itself a list); for example:

    52         'a/complete/path/in/one/string'

    53         ['some', 'path', 'parts']

    54         [['path', 'parts', 'and', 'a'], 'link ID']

    55 

    56   Returns:

    57     None if path_parts is False (None, empty string, etc.) or if

    58     any list elements are False (an empty list, empty string, etc.);

    59     otherwise, the combined string with the necessary separators.

    60   """

    61   if not path_parts:

    62     # completely empty input, so return early

    63     return None

    64 

    65   if not isinstance(path_parts, (list, tuple)):

    66     # a single path string, so just return it as-is (nothing to do)

    67     return path_parts

    68   

    69   flattened_parts = []

    70   

    71   for part in path_parts:

    72     if not part:

    73       # encountered a "False" element, which invalidates everything else

    74       return None    

    75   

    76     if isinstance(part, (list, tuple)):

    77       flattened_parts.extend(part)

    78     else:

    79       flattened_parts.append(part)

    80 

    81   return '/'.join(flattened_parts)