src/catalogue/helpers.py

   1 from datetime import date
   2 from functools import wraps
   3 from os.path import join
   4 from os import listdir, stat
   5 from shutil import move, rmtree
   6 from django.conf import settings
   7 import re
   8 import filecmp
   9
  10 from django.db.models import Count
  11
  12
  13 def active_tab(tab):
  14     """
  15         View decorator, which puts tab info on a request.
  16     """
  17     def wrapper(f):
  18         @wraps(f)
  19         def wrapped(request, *args, **kwargs):
  20             request.catalogue_active_tab = tab
  21             return f(request, *args, **kwargs)
  22         return wrapped
  23     return wrapper
  24
  25
  26 def cached_in_field(field_name):
  27     def decorator(f):
  28         @property
  29         @wraps(f)
  30         def wrapped(self, *args, **kwargs):
  31             value = getattr(self, field_name)
  32             if value is None:
  33                 value = f(self, *args, **kwargs)
  34                 type(self)._default_manager.filter(pk=self.pk).update(**{field_name: value})
  35             return value
  36         return wrapped
  37     return decorator
  38
  39
  40 def parse_isodate(isodate):
  41     try:
  42         return date(*[int(p) for p in isodate.split('-')])
  43     except (AttributeError, TypeError, ValueError):
  44         raise ValueError("Not a date in ISO format.")
  45
  46
  47 class GalleryMerger(object):
  48     def __init__(self, dest_gallery, src_gallery):
  49         self.dest = dest_gallery
  50         self.src = src_gallery
  51         self.dest_size = None
  52         self.src_size = None
  53         self.num_deleted = 0
  54
  55     @staticmethod
  56     def path(gallery):
  57         return join(settings.MEDIA_ROOT, settings.IMAGE_DIR, gallery)
  58
  59     @staticmethod
  60     def get_prefix(name):
  61         m = re.match(r"^([0-9])-", name)
  62         if m:
  63             return int(m.groups()[0])
  64         return None
  65
  66     @staticmethod
  67     def set_prefix(name, prefix, always=False):
  68         m = not always and re.match(r"^([0-9])-", name)
  69         return "%1d-%s" % (prefix, m and name[2:] or name)
  70
  71     @property
  72     def was_merged(self):
  73         "Check if we have gallery size recorded"
  74         return self.dest_size is not None
  75
  76     def merge(self):
  77         if not self.dest:
  78             return self.src
  79         if not self.src:
  80             return self.dest
  81
  82         files = listdir(self.path(self.dest))
  83         files.sort()
  84         self.dest_size = len(files)
  85         files_other = listdir(self.path(self.src))
  86         files_other.sort()
  87         self.src_size = len(files_other)
  88
  89         if files and files_other:
  90             if filecmp.cmp(
  91                     join(self.path(self.dest), files[-1]),
  92                     join(self.path(self.src), files_other[0]),
  93                     False
  94                     ):
  95                 files_other.pop(0)
  96                 self.num_deleted = 1
  97
  98         prefixes = {}
  99         renamed_files = {}
 100         renamed_files_other = {}
 101         last_pfx = -1
 102
 103         # check if all elements of my files have a prefix
 104         files_prefixed = True
 105         for f in files:
 106             p = self.get_prefix(f)
 107             if p:
 108                 if p > last_pfx: last_pfx = p
 109             else:
 110                 files_prefixed = False
 111                 break
 112
 113         # if not, add a 0 prefix to them
 114         if not files_prefixed:
 115             prefixes[0] = 0
 116             for f in files:
 117                 renamed_files[f] = self.set_prefix(f, 0, True)
 118
 119         # two cases here - either all are prefixed or not.
 120         files_other_prefixed = True
 121         for f in files_other:
 122             pfx = self.get_prefix(f)
 123             if pfx is not None:
 124                 if not pfx in prefixes:
 125                     last_pfx += 1
 126                     prefixes[pfx] = last_pfx
 127                 renamed_files_other[f] = self.set_prefix(f, prefixes[pfx])
 128             else:
 129                 # ops, not all files here were prefixed.
 130                 files_other_prefixed = False
 131                 break
 132
 133         # just set a 1- prefix to all of them
 134         if not files_other_prefixed:
 135             for f in files_other:
 136                 renamed_files_other[f] = self.set_prefix(f, 1, True)
 137
 138         # finally, move / rename files.
 139         for frm, to in renamed_files.items():
 140             move(join(self.path(self.dest), frm),
 141                         join(self.path(self.dest), to))
 142         for frm, to in renamed_files_other.items():
 143             move(join(self.path(self.src), frm),
 144                         join(self.path(self.dest), to))
 145
 146         rmtree(join(self.path(self.src)))
 147         return self.dest