apps/catalogue/helpers.py

   1 # -*- coding: utf-8 -*-
   2 import filecmp
   3 import json
   4 import re
   5 from datetime import date
   6 from functools import wraps
   7 from inspect import getargspec
   8 from os import listdir
   9 from os.path import join
  10 from shutil import move, rmtree
  11
  12 from django.conf import settings
  13 from django.http import HttpResponse
  14 from django.template import RequestContext
  15 from django.template.loader import render_to_string
  16
  17
  18 def active_tab(tab):
  19     """
  20         View decorator, which puts tab info on a request.
  21     """
  22     def wrapper(f):
  23         @wraps(f)
  24         def wrapped(request, *args, **kwargs):
  25             request.catalogue_active_tab = tab
  26             return f(request, *args, **kwargs)
  27         return wrapped
  28     return wrapper
  29
  30
  31 def cached_in_field(field_name):
  32     def decorator(f):
  33         @property
  34         @wraps(f)
  35         def wrapped(self, *args, **kwargs):
  36             value = getattr(self, field_name)
  37             if value is None:
  38                 value = f(self, *args, **kwargs)
  39                 type(self)._default_manager.filter(pk=self.pk).update(**{field_name: value})
  40             return value
  41         return wrapped
  42     return decorator
  43
  44
  45 class AjaxError(Exception):
  46     pass
  47
  48
  49 def ajax(method, template=None, login_required=False, permission_required=None):
  50     def decorator(fun):
  51         @wraps(fun)
  52         def ajax_view(request):
  53             kwargs = {}
  54             request_params = None
  55             if method == 'post':
  56                 request_params = request.POST
  57             elif method == 'get':
  58                 request_params = request.GET
  59             fun_params, xx, fun_kwargs, defaults = getargspec(fun)
  60             if defaults:
  61                 required_params = fun_params[1:-len(defaults)]
  62             else:
  63                 required_params = fun_params[1:]
  64             missing_params = set(required_params) - set(request_params)
  65             if missing_params:
  66                 res = {
  67                     'result': 'error',
  68                     'msg': 'missing params: %s' % ', '.join(missing_params),
  69                 }
  70             else:
  71                 if request_params:
  72                     request_params = dict(
  73                         (key, json.loads(value))
  74                         for key, value in request_params.iteritems()
  75                         if fun_kwargs or key in fun_params)
  76                     kwargs.update(request_params)
  77                 res = None
  78                 if login_required and not request.user.is_authenticated():
  79                     res = {'result': 'error', 'msg': 'logout'}
  80                 if (permission_required and
  81                         not request.user.has_perm(permission_required)):
  82                     res = {'result': 'error', 'msg': 'access denied'}
  83             if not res:
  84                 try:
  85                     res = fun(request, **kwargs)
  86                     if res and template:
  87                         res = {'html': render_to_string(template, res, RequestContext(request))}
  88                 except AjaxError as e:
  89                     res = {'result': e.args[0]}
  90             if 'result' not in res:
  91                 res['result'] = 'ok'
  92             return HttpResponse(json.dumps(res), content_type='application/json; charset=utf-8')
  93
  94         return ajax_view
  95
  96     return decorator
  97
  98
  99 def parse_isodate(isodate):
 100     try:
 101         return date(*[int(p) for p in isodate.split('-')])
 102     except (AttributeError, TypeError, ValueError):
 103         raise ValueError("Not a date in ISO format.")
 104
 105
 106 class GalleryMerger(object):
 107     def __init__(self, dest_gallery, src_gallery):
 108         self.dest = dest_gallery
 109         self.src = src_gallery
 110         self.dest_size = None
 111         self.src_size = None
 112         self.num_deleted = 0
 113
 114     @staticmethod
 115     def path(gallery):
 116         return join(settings.MEDIA_ROOT, settings.IMAGE_DIR, gallery)
 117
 118     @staticmethod
 119     def get_prefix(name):
 120         m = re.match(r"^([0-9])-", name)
 121         if m:
 122             return int(m.groups()[0])
 123         return None
 124
 125     @staticmethod
 126     def set_prefix(name, prefix, always=False):
 127         m = not always and re.match(r"^([0-9])-", name)
 128         return "%1d-%s" % (prefix, m and name[2:] or name)
 129
 130     @property
 131     def was_merged(self):
 132         """Check if we have gallery size recorded"""
 133         return self.dest_size is not None
 134
 135     def merge(self):
 136         if not self.dest:
 137             return self.src
 138         if not self.src:
 139             return self.dest
 140
 141         files = listdir(self.path(self.dest))
 142         files.sort()
 143         self.dest_size = len(files)
 144         files_other = listdir(self.path(self.src))
 145         files_other.sort()
 146         self.src_size = len(files_other)
 147
 148         if files and files_other:
 149             print "compare %s with %s" % (files[-1], files_other[0])
 150             if filecmp.cmp(
 151                     join(self.path(self.dest), files[-1]),
 152                     join(self.path(self.src), files_other[0]),
 153                     False
 154                     ):
 155                 files_other.pop(0)
 156                 self.num_deleted = 1
 157
 158         prefixes = {}
 159         renamed_files = {}
 160         renamed_files_other = {}
 161         last_pfx = -1
 162
 163         # check if all elements of my files have a prefix
 164         files_prefixed = True
 165         for f in files:
 166             p = self.get_prefix(f)
 167             if p:
 168                 if p > last_pfx:
 169                     last_pfx = p
 170             else:
 171                 files_prefixed = False
 172                 break
 173
 174         # if not, add a 0 prefix to them
 175         if not files_prefixed:
 176             prefixes[0] = 0
 177             for f in files:
 178                 renamed_files[f] = self.set_prefix(f, 0, True)
 179
 180         # two cases here - either all are prefixed or not.
 181         files_other_prefixed = True
 182         for f in files_other:
 183             pfx = self.get_prefix(f)
 184             if pfx is not None:
 185                 if pfx not in prefixes:
 186                     last_pfx += 1
 187                     prefixes[pfx] = last_pfx
 188                 renamed_files_other[f] = self.set_prefix(f, prefixes[pfx])
 189             else:
 190                 # ops, not all files here were prefixed.
 191                 files_other_prefixed = False
 192                 break
 193
 194         # just set a 1- prefix to all of them
 195         if not files_other_prefixed:
 196             for f in files_other:
 197                 renamed_files_other[f] = self.set_prefix(f, 1, True)
 198
 199         # finally, move / rename files.
 200         for frm, to in renamed_files.items():
 201             move(join(self.path(self.dest), frm), join(self.path(self.dest), to))
 202         for frm, to in renamed_files_other.items():
 203             move(join(self.path(self.src), frm), join(self.path(self.dest), to))
 204
 205         rmtree(join(self.path(self.src)))
 206         return self.dest