apps/wiki/helpers.py

   1 from django import http
   2 from django.utils import simplejson as json
   3 from django.utils.functional import Promise
   4 from datetime import datetime
   5 from functools import wraps
   6
   7
   8 class ExtendedEncoder(json.JSONEncoder):
   9
  10     def default(self, obj):
  11         if isinstance(obj, Promise):
  12             return unicode(obj)
  13
  14         if isinstance(obj, datetime):
  15             return datetime.ctime(obj) + " " + (datetime.tzname(obj) or 'GMT')
  16
  17         return json.JSONEncoder.default(self, obj)
  18
  19
  20 # shortcut for JSON reponses
  21 class JSONResponse(http.HttpResponse):
  22
  23     def __init__(self, data={}, **kwargs):
  24         # get rid of mimetype
  25         kwargs.pop('mimetype', None)
  26
  27         data = json.dumps(data, cls=ExtendedEncoder)
  28         super(JSONResponse, self).__init__(data, mimetype="application/json", **kwargs)
  29
  30
  31 # return errors
  32 class JSONFormInvalid(JSONResponse):
  33     def __init__(self, form):
  34         super(JSONFormInvalid, self).__init__(form.errors, status=400)
  35
  36
  37 class JSONServerError(JSONResponse):
  38     def __init__(self, *args, **kwargs):
  39         kwargs['status'] = 500
  40         super(JSONServerError, self).__init__(*args, **kwargs)
  41
  42
  43 def ajax_login_required(view):
  44     @wraps(view)
  45     def authenticated_view(request, *args, **kwargs):
  46         if not request.user.is_authenticated():
  47             return http.HttpResponse("Login required.", status=401, mimetype="text/plain")
  48         return view(request, *args, **kwargs)
  49     return authenticated_view
  50
  51
  52 def ajax_require_permission(permission):
  53     def decorator(view):
  54         @wraps(view)
  55         def authorized_view(request, *args, **kwargs):
  56             if not request.user.has_perm(permission):
  57                 return http.HttpResponse("Access Forbidden.", status=403, mimetype="text/plain")
  58             return view(request, *args, **kwargs)
  59         return authorized_view
  60     return decorator
  61
  62 import collections
  63
  64 def recursive_groupby(iterable):
  65     """
  66 #    >>> recursive_groupby([1,2,3,4,5])
  67 #    [1, 2, 3, 4, 5]
  68
  69     >>> recursive_groupby([[1]])
  70     [1]
  71
  72     >>> recursive_groupby([('a', 1),('a', 2), 3, ('b', 4), 5])
  73     ['a', [1, 2], 3, 'b', [4], 5]
  74
  75     >>> recursive_groupby([('a', 'x', 1),('a', 'x', 2), ('a', 'x', 3)])
  76     ['a', ['x', [1, 2, 3]]]
  77
  78     """
  79
  80     def _generator(iterator):
  81         group = None
  82         grouper = None
  83
  84         for item in iterator:
  85             if not isinstance(item, collections.Sequence):
  86                 if grouper is not None:
  87                     yield grouper
  88                     if len(group):
  89                         yield recursive_groupby(group)
  90                     group = None
  91                     grouper = None
  92                 yield item
  93                 continue
  94             elif len(item) == 1:
  95                 if grouper is not None:
  96                     yield grouper
  97                     if len(group):
  98                         yield recursive_groupby(group)
  99                     group = None
 100                     grouper = None
 101                 yield item[0]
 102                 continue
 103             elif not len(item):
 104                 continue
 105
 106             if grouper is None:
 107                 group = [item[1:]]
 108                 grouper = item[0]
 109                 continue
 110
 111             if grouper != item[0]:
 112                 if grouper is not None:
 113                     yield grouper
 114                     if len(group):
 115                         yield recursive_groupby(group)
 116                     group = None
 117                     grouper = None
 118                 group = [item[1:]]
 119                 grouper = item[0]
 120                 continue
 121
 122             group.append(item[1:])
 123
 124         if grouper is not None:
 125             yield grouper
 126             if len(group):
 127                 yield recursive_groupby(group)
 128             group = None
 129             grouper = None
 130
 131     return list(_generator(iterable))
 132
 133
 134 def active_tab(tab):
 135     """
 136         View decorator, which puts tab info on a request.
 137     """
 138     def wrapper(f):
 139         @wraps(f)
 140         def wrapped(request, *args, **kwargs):
 141             request.wiki_active_tab = tab
 142             return f(request, *args, **kwargs)
 143         return wrapped
 144     return wrapper
 145
 146
 147 class BookChunks(object):
 148     """
 149         Yields the chunks of a book.
 150     """
 151
 152     def __init__(self, book):
 153         self.book = book
 154
 155     @property
 156     def chunks(self):
 157         return self.book.chunk_set.all()
 158
 159
 160 class ChoiceChunks(BookChunks):
 161     """
 162         Associates the given chunks iterable for a book.
 163     """
 164
 165     chunks = None
 166
 167     def __init__(self, book, chunks):
 168         self.book = book
 169         self.chunks = chunks
 170