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 """Helpers used to render lists.

    18 """

    19 

    20 __authors__ = [

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

    22   ]

    23 

    24 

    25 DEF_LIMIT = 10

    26 

    27 def getListParemeters(offset=None, limit=None):

    28   """Updates and validates offset and limit values of the list.

    29 

    30   Args:

    31     offset: offset in list which defines first item to return

    32     limit: max amount of items per page

    33 

    34   Returns:

    35     updated offset and limit values

    36   """

    37   # update offset value 

    38   if offset:

    39     try:

    40       offset = int(offset)

    41     except:

    42       offset = 0

    43     else:

    44       offset = max(0, offset)

    45   else:

    46     offset = 0

    47   

    48   # update limit value

    49   if limit:

    50     try:

    51       limit = int(limit)

    52     except:

    53       limit = DEF_LIMIT

    54     else:

    55       limit = max(1, min(limit, 100))

    56   else:

    57     limit = DEF_LIMIT

    58   

    59   return offset, limit

    60 

    61 DEF_LIST_TEMPLATES = {'list_main': 'soc/list/list_main.html',

    62                       'list_pagination': 'soc/list/list_pagination.html',

    63                       'list_row': 'soc/list/list_row.html',

    64                       'list_heading': 'soc/list/list_heading.html'}

    65 

    66 def setList(request, context, list_data,

    67             offset=0, limit=0, list_templates=DEF_LIST_TEMPLATES):

    68   """Updates template context dict with variables used for rendering lists.

    69 

    70   Args:

    71     request: the Django HTTP request object

    72     context: the template context dict to be updated in-place (pass in a copy

    73       if the original must not be modified), or None if a new one is to be

    74       created; any existing fields already present in the context dict passed

    75       in by the caller are left unaltered 

    76     list_data: array of data to be displayed in the list

    77     offset: offset in list which defines first item to return

    78     limit: max amount of items per page

    79     list_templates: templates that are used when rendering list

    80 

    81   Returns:

    82     updated template context dict supplied by the caller or a new context

    83     dict if the caller supplied None

    84 

    85     {

    86       'list_data': list data to be displayed 

    87       'list_main': url to list main template

    88       'list_pagination': url to list pagination template

    89       'list_row': url to list row template

    90       'list_heading': url to list heading template

    91       'limit': max amount of items per page,

    92       'newest': url to first page of the list 

    93       'prev': url to previous page 

    94       'next': url to next page

    95       'first': offset of the first item in the list

    96       'last': offest of the lst item in the list

    97     }

    98   """  

    99   if not list_data:

   100     list_data = []

   101   

   102   more = bool(list_data[limit:])

   103   if more:

   104     del list_data[limit:]

   105   if more:

   106     next = request.path + '?offset=%d&limit=%d' % (offset+limit, limit)

   107   else:

   108     next = ''

   109   if offset > 0:

   110     prev = request.path + '?offset=%d&limit=%d' % (max(0, offset-limit), limit)

   111   else:

   112     prev = ''

   113   newest = ''

   114   if offset > limit:

   115     newest = request.path + '?limit=%d' % limit

   116   

   117   if not context:

   118     context = {}

   119   

   120   context.update(

   121     {'list_data': list_data, 

   122      'list_main': list_templates['list_main'],

   123      'list_pagination': list_templates['list_pagination'],

   124      'list_row': list_templates['list_row'],

   125      'list_heading': list_templates['list_heading'],

   126      'limit': limit,

   127      'newest': newest, 

   128      'prev': prev, 

   129      'next': next,

   130      'first': offset+1,

   131      'last': len(list_data) > 1 and offset+len(list_data) or None})

   132   

   133   return context