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 """Common helper functions.

    18 """

    19 

    20 __authors__ = [

    21   '"Pawel Solyga" <pawel.solyga@gmail.com>',

    22   ]

    23 

    24 

    25 import re

    26 

    27 

    28 LINKNAME_PATTERN = r'''(?x)

    29     ^

    30     [0-9a-z]   # start with ASCII digit or lowercase

    31     (

    32      [0-9a-z]  # additional ASCII digit or lowercase

    33      |         # -OR-

    34      _[0-9a-z] # underscore and ASCII digit or lowercase

    35     )*         # zero or more of OR group

    36     $

    37 '''

    38 

    39 LINKNAME_REGEX = re.compile(LINKNAME_PATTERN)

    40 

    41 def isLinkNameFormatValid(link_name):

    42   """Returns True if link_name is in a valid format.

    43 

    44   Args:

    45     link_name: link name used in URLs for identification

    46   """

    47   if LINKNAME_REGEX.match(link_name):

    48     return True

    49   return False