apps/catalogue/views.py

   1 # -*- coding: utf-8 -*-
   2 # This file is part of Wolnelektury, licensed under GNU Affero GPLv3 or later.
   3 # Copyright © Fundacja Nowoczesna Polska. See NOTICE for more information.
   4 #
   5 import tempfile
   6 import zipfile
   7 import sys
   8 import pprint
   9 import traceback
  10 import re
  11 import itertools
  12 from operator import itemgetter
  13
  14 from django.conf import settings
  15 from django.template import RequestContext
  16 from django.shortcuts import render_to_response, get_object_or_404
  17 from django.http import HttpResponse, HttpResponseRedirect, Http404
  18 from django.core.urlresolvers import reverse
  19 from django.db.models import Q
  20 from django.contrib.auth.decorators import login_required, user_passes_test
  21 from django.utils.datastructures import SortedDict
  22 from django.views.decorators.http import require_POST
  23 from django.contrib import auth
  24 from django.contrib.auth.forms import UserCreationForm, AuthenticationForm
  25 from django.utils import simplejson
  26 from django.utils.functional import Promise
  27 from django.utils.encoding import force_unicode
  28 from django.utils.http import urlquote_plus
  29 from django.views.decorators import cache
  30 from django.utils.translation import ugettext as _
  31 from django.views.generic.list_detail import object_list
  32
  33 from catalogue import models
  34 from catalogue import forms
  35 from catalogue.utils import split_tags
  36 from newtagging import views as newtagging_views
  37
  38
  39 staff_required = user_passes_test(lambda user: user.is_staff)
  40
  41
  42 class LazyEncoder(simplejson.JSONEncoder):
  43     def default(self, obj):
  44         if isinstance(obj, Promise):
  45             return force_unicode(obj)
  46         return obj
  47
  48 # shortcut for JSON reponses
  49 class JSONResponse(HttpResponse):
  50     def __init__(self, data={}, callback=None, **kwargs):
  51         # get rid of mimetype
  52         kwargs.pop('mimetype', None)
  53         data = simplejson.dumps(data)
  54         if callback:
  55             data = callback + "(" + data + ");"
  56         super(JSONResponse, self).__init__(data, mimetype="application/json", **kwargs)
  57
  58
  59 def main_page(request):
  60     if request.user.is_authenticated():
  61         shelves = models.Tag.objects.filter(category='set', user=request.user)
  62         new_set_form = forms.NewSetForm()
  63
  64     tags = models.Tag.objects.exclude(category__in=('set', 'book'))
  65     for tag in tags:
  66         tag.count = tag.get_count()
  67     categories = split_tags(tags)
  68     fragment_tags = categories.get('theme', [])
  69
  70     form = forms.SearchForm()
  71     return render_to_response('catalogue/main_page.html', locals(),
  72         context_instance=RequestContext(request))
  73
  74
  75 def book_list(request):
  76     form = forms.SearchForm()
  77
  78     books_by_parent = {}
  79     for book in models.Book.objects.all().order_by('parent_number'):
  80         books_by_parent.setdefault(book.parent, []).append(book)
  81
  82     orphans = []
  83     books_by_author = SortedDict()
  84     for tag in models.Tag.objects.filter(category='author'):
  85         books_by_author[tag] = []
  86
  87     for book in books_by_parent[None]:
  88         authors = list(book.tags.filter(category='author'))
  89         if authors:
  90             for author in authors:
  91                 books_by_author[author].append(book)
  92         else:
  93             orphans.append(book)
  94
  95     return render_to_response('catalogue/book_list.html', locals(),
  96         context_instance=RequestContext(request))
  97
  98
  99 def differentiate_tags(request, tags, ambiguous_slugs):
 100     beginning = '/'.join(tag.url_chunk for tag in tags)
 101     unparsed = '/'.join(ambiguous_slugs[1:])
 102     options = []
 103     for tag in models.Tag.objects.exclude(category='book').filter(slug=ambiguous_slugs[0]):
 104         options.append({
 105             'url_args': '/'.join((beginning, tag.url_chunk, unparsed)).strip('/'),
 106             'tags': [tag]
 107         })
 108     return render_to_response('catalogue/differentiate_tags.html',
 109                 {'tags': tags, 'options': options, 'unparsed': ambiguous_slugs[1:]},
 110                 context_instance=RequestContext(request))
 111
 112
 113 def tagged_object_list(request, tags=''):
 114     try:
 115         tags = models.Tag.get_tag_list(tags)
 116     except models.Tag.DoesNotExist:
 117         raise Http404
 118     except models.Tag.MultipleObjectsReturned, e:
 119         return differentiate_tags(request, e.tags, e.ambiguous_slugs)
 120
 121     try:
 122         if len(tags) > settings.MAX_TAG_LIST:
 123             raise Http404
 124     except AttributeError:
 125         pass
 126
 127     if len([tag for tag in tags if tag.category == 'book']):
 128         raise Http404
 129
 130     theme_is_set = [tag for tag in tags if tag.category == 'theme']
 131     shelf_is_set = [tag for tag in tags if tag.category == 'set']
 132     only_shelf = shelf_is_set and len(tags) == 1
 133     only_my_shelf = only_shelf and request.user.is_authenticated() and request.user == tags[0].user
 134
 135     objects = only_author = pd_counter = None
 136     categories = {}
 137
 138     if theme_is_set:
 139         shelf_tags = [tag for tag in tags if tag.category == 'set']
 140         fragment_tags = [tag for tag in tags if tag.category != 'set']
 141         fragments = models.Fragment.tagged.with_all(fragment_tags)
 142
 143         if shelf_tags:
 144             books = models.Book.tagged.with_all(shelf_tags).order_by()
 145             l_tags = models.Tag.objects.filter(category='book', slug__in=[book.book_tag_slug() for book in books])
 146             fragments = models.Fragment.tagged.with_any(l_tags, fragments)
 147
 148         # newtagging goes crazy if we just try:
 149         #related_tags = models.Tag.objects.usage_for_queryset(fragments, counts=True,
 150         #                    extra={'where': ["catalogue_tag.category != 'book'"]})
 151         fragment_keys = [fragment.pk for fragment in fragments]
 152         if fragment_keys:
 153             related_tags = models.Fragment.tags.usage(counts=True,
 154                                 filters={'pk__in': fragment_keys},
 155                                 extra={'where': ["catalogue_tag.category != 'book'"]})
 156             related_tags = (tag for tag in related_tags if tag not in fragment_tags)
 157             categories = split_tags(related_tags)
 158
 159             objects = fragments
 160     else:
 161         # get relevant books and their tags
 162         objects = models.Book.tagged.with_all(tags).order_by()
 163         if not shelf_is_set:
 164             # eliminate descendants
 165             l_tags = models.Tag.objects.filter(category='book', slug__in=[book.book_tag_slug() for book in objects])
 166             descendants_keys = [book.pk for book in models.Book.tagged.with_any(l_tags)]
 167             if descendants_keys:
 168                 objects = objects.exclude(pk__in=descendants_keys)
 169
 170         # get related tags from `tag_counter` and `theme_counter`
 171         related_counts = {}
 172         tags_pks = [tag.pk for tag in tags]
 173         for book in objects:
 174             for tag_pk, value in itertools.chain(book.tag_counter.iteritems(), book.theme_counter.iteritems()):
 175                 if tag_pk in tags_pks:
 176                     continue
 177                 related_counts[tag_pk] = related_counts.get(tag_pk, 0) + value
 178         related_tags = models.Tag.objects.filter(pk__in=related_counts.keys())
 179         related_tags = [tag for tag in related_tags if tag not in tags]
 180         for tag in related_tags:
 181             tag.count = related_counts[tag.pk]
 182
 183         categories = split_tags(related_tags)
 184         del related_tags
 185
 186     if not objects:
 187         only_author = len(tags) == 1 and tags[0].category == 'author'
 188         pd_counter = only_author and tags[0].goes_to_pd()
 189         objects = models.Book.objects.none()
 190
 191     return object_list(
 192         request,
 193         objects,
 194         template_name='catalogue/tagged_object_list.html',
 195         extra_context={
 196             'categories': categories,
 197             'only_shelf': only_shelf,
 198             'only_author': only_author,
 199             'pd_counter': pd_counter,
 200             'only_my_shelf': only_my_shelf,
 201             'formats_form': forms.DownloadFormatsForm(),
 202
 203             'tags': tags,
 204         }
 205     )
 206
 207
 208 def book_fragments(request, book_slug, theme_slug):
 209     book = get_object_or_404(models.Book, slug=book_slug)
 210     book_tag = get_object_or_404(models.Tag, slug='l-' + book_slug, category='book')
 211     theme = get_object_or_404(models.Tag, slug=theme_slug, category='theme')
 212     fragments = models.Fragment.tagged.with_all([book_tag, theme])
 213
 214     form = forms.SearchForm()
 215     return render_to_response('catalogue/book_fragments.html', locals(),
 216         context_instance=RequestContext(request))
 217
 218
 219 def book_detail(request, slug):
 220     try:
 221         book = models.Book.objects.get(slug=slug)
 222     except models.Book.DoesNotExist:
 223         return book_stub_detail(request, slug)
 224
 225     book_tag = book.book_tag()
 226     tags = list(book.tags.filter(~Q(category='set')))
 227     categories = split_tags(tags)
 228     book_children = book.children.all().order_by('parent_number')
 229
 230     _book = book
 231     parents = []
 232     while _book.parent:
 233         parents.append(_book.parent)
 234         _book = _book.parent
 235     parents = reversed(parents)
 236
 237     theme_counter = book.theme_counter
 238     book_themes = models.Tag.objects.filter(pk__in=theme_counter.keys())
 239     for tag in book_themes:
 240         tag.count = theme_counter[tag.pk]
 241
 242     extra_info = book.get_extra_info_value()
 243
 244     form = forms.SearchForm()
 245     return render_to_response('catalogue/book_detail.html', locals(),
 246         context_instance=RequestContext(request))
 247
 248
 249 def book_stub_detail(request, slug):
 250     book = get_object_or_404(models.BookStub, slug=slug)
 251     pd_counter = book.pd
 252     form = forms.SearchForm()
 253
 254     return render_to_response('catalogue/book_stub_detail.html', locals(),
 255         context_instance=RequestContext(request))
 256
 257
 258 def book_text(request, slug):
 259     book = get_object_or_404(models.Book, slug=slug)
 260     book_themes = {}
 261     for fragment in book.fragments.all():
 262         for theme in fragment.tags.filter(category='theme'):
 263             book_themes.setdefault(theme, []).append(fragment)
 264
 265     book_themes = book_themes.items()
 266     book_themes.sort(key=lambda s: s[0].sort_key)
 267     return render_to_response('catalogue/book_text.html', locals(),
 268         context_instance=RequestContext(request))
 269
 270
 271 # ==========
 272 # = Search =
 273 # ==========
 274
 275 def _no_diacritics_regexp(query):
 276     """ returns a regexp for searching for a query without diacritics
 277
 278     should be locale-aware """
 279     names = {
 280         u'a':u'aąĄ', u'c':u'cćĆ', u'e':u'eęĘ', u'l': u'lłŁ', u'n':u'nńŃ', u'o':u'oóÓ', u's':u'sśŚ', u'z':u'zźżŹŻ',
 281         u'ą':u'ąĄ', u'ć':u'ćĆ', u'ę':u'ęĘ', u'ł': u'łŁ', u'ń':u'ńŃ', u'ó':u'óÓ', u'ś':u'śŚ', u'ź':u'źŹ', u'ż':u'żŻ'
 282         }
 283     def repl(m):
 284         l = m.group()
 285         return u"(%s)" % '|'.join(names[l])
 286     return re.sub(u'[%s]' % (u''.join(names.keys())), repl, query)
 287
 288 def unicode_re_escape(query):
 289     """ Unicode-friendly version of re.escape """
 290     return re.sub('(?u)(\W)', r'\\\1', query)
 291
 292 def _word_starts_with(name, prefix):
 293     """returns a Q object getting models having `name` contain a word
 294     starting with `prefix`
 295
 296     We define word characters as alphanumeric and underscore, like in JS.
 297
 298     Works for MySQL, PostgreSQL, Oracle.
 299     For SQLite, _sqlite* version is substituted for this.
 300     """
 301     kwargs = {}
 302
 303     prefix = _no_diacritics_regexp(unicode_re_escape(prefix))
 304     # can't use [[:<:]] (word start),
 305     # but we want both `xy` and `(xy` to catch `(xyz)`
 306     kwargs['%s__iregex' % name] = u"(^|[^[:alnum:]_])%s" % prefix
 307
 308     return Q(**kwargs)
 309
 310
 311 def _sqlite_word_starts_with(name, prefix):
 312     """ version of _word_starts_with for SQLite
 313
 314     SQLite in Django uses Python re module
 315     """
 316     kwargs = {}
 317     prefix = _no_diacritics_regexp(unicode_re_escape(prefix))
 318     kwargs['%s__iregex' % name] = ur"(^|(?<=[^\wąćęłńóśźżĄĆĘŁŃÓŚŹŻ]))%s" % prefix
 319     return Q(**kwargs)
 320
 321
 322 if settings.DATABASE_ENGINE == 'sqlite3':
 323     _word_starts_with = _sqlite_word_starts_with
 324
 325
 326 def _tags_starting_with(prefix, user=None):
 327     prefix = prefix.lower()
 328     book_stubs = models.BookStub.objects.filter(_word_starts_with('title', prefix))
 329     books = models.Book.objects.filter(_word_starts_with('title', prefix))
 330     book_stubs = filter(lambda x: x not in books, book_stubs)
 331     tags = models.Tag.objects.filter(_word_starts_with('name', prefix))
 332     if user and user.is_authenticated():
 333         tags = tags.filter(~Q(category='book') & (~Q(category='set') | Q(user=user)))
 334     else:
 335         tags = tags.filter(~Q(category='book') & ~Q(category='set'))
 336     return list(books) + list(tags) + list(book_stubs)
 337
 338
 339 def _get_result_link(match, tag_list):
 340     if isinstance(match, models.Book) or isinstance(match, models.BookStub):
 341         return match.get_absolute_url()
 342     else:
 343         return reverse('catalogue.views.tagged_object_list',
 344             kwargs={'tags': '/'.join(tag.url_chunk for tag in tag_list + [match])}
 345         )
 346
 347 def _get_result_type(match):
 348     if isinstance(match, models.Book) or isinstance(match, models.BookStub):
 349         type = 'book'
 350     else:
 351         type = match.category
 352     return type
 353
 354
 355
 356 def find_best_matches(query, user=None):
 357     """ Finds a Book, Tag or Bookstub best matching a query.
 358
 359     Returns a with:
 360       - zero elements when nothing is found,
 361       - one element when a best result is found,
 362       - more then one element on multiple exact matches
 363
 364     Raises a ValueError on too short a query.
 365     """
 366
 367     query = query.lower()
 368     if len(query) < 2:
 369         raise ValueError("query must have at least two characters")
 370
 371     result = tuple(_tags_starting_with(query, user))
 372     exact_matches = tuple(res for res in result if res.name.lower() == query)
 373     if exact_matches:
 374         return exact_matches
 375     else:
 376         return result[:1]
 377
 378
 379 def search(request):
 380     tags = request.GET.get('tags', '')
 381     prefix = request.GET.get('q', '')
 382
 383     try:
 384         tag_list = models.Tag.get_tag_list(tags)
 385     except:
 386         tag_list = []
 387
 388     try:
 389         result = find_best_matches(prefix, request.user)
 390     except ValueError:
 391         return render_to_response('catalogue/search_too_short.html', {'tags':tag_list, 'prefix':prefix},
 392             context_instance=RequestContext(request))
 393
 394     if len(result) == 1:
 395         return HttpResponseRedirect(_get_result_link(result[0], tag_list))
 396     elif len(result) > 1:
 397         return render_to_response('catalogue/search_multiple_hits.html',
 398             {'tags':tag_list, 'prefix':prefix, 'results':((x, _get_result_link(x, tag_list), _get_result_type(x)) for x in result)},
 399             context_instance=RequestContext(request))
 400     else:
 401         return render_to_response('catalogue/search_no_hits.html', {'tags':tag_list, 'prefix':prefix},
 402             context_instance=RequestContext(request))
 403
 404
 405 def tags_starting_with(request):
 406     prefix = request.GET.get('q', '')
 407     # Prefix must have at least 2 characters
 408     if len(prefix) < 2:
 409         return HttpResponse('')
 410     tags_list = []
 411     result = ""
 412     for tag in _tags_starting_with(prefix, request.user):
 413         if not tag.name in tags_list:
 414             result += "\n" + tag.name
 415             tags_list.append(tag.name)
 416     return HttpResponse(result)
 417
 418 def json_tags_starting_with(request, callback=None):
 419     # Callback for JSONP
 420     prefix = request.GET.get('q', '')
 421     callback = request.GET.get('callback', '')
 422     # Prefix must have at least 2 characters
 423     if len(prefix) < 2:
 424         return HttpResponse('')
 425     tags_list = []
 426     result = ""
 427     for tag in _tags_starting_with(prefix, request.user):
 428         if not tag.name in tags_list:
 429             result += "\n" + tag.name
 430             tags_list.append(tag.name)
 431     dict_result = {"matches": tags_list}
 432     return JSONResponse(dict_result, callback)
 433
 434 # ====================
 435 # = Shelf management =
 436 # ====================
 437 @login_required
 438 @cache.never_cache
 439 def user_shelves(request):
 440     shelves = models.Tag.objects.filter(category='set', user=request.user)
 441     new_set_form = forms.NewSetForm()
 442     return render_to_response('catalogue/user_shelves.html', locals(),
 443             context_instance=RequestContext(request))
 444
 445 @cache.never_cache
 446 def book_sets(request, slug):
 447     book = get_object_or_404(models.Book, slug=slug)
 448     user_sets = models.Tag.objects.filter(category='set', user=request.user)
 449     book_sets = book.tags.filter(category='set', user=request.user)
 450
 451     if not request.user.is_authenticated():
 452         return HttpResponse(_('<p>To maintain your shelves you need to be logged in.</p>'))
 453
 454     if request.method == 'POST':
 455         form = forms.ObjectSetsForm(book, request.user, request.POST)
 456         if form.is_valid():
 457             old_shelves = list(book.tags.filter(category='set'))
 458             new_shelves = [models.Tag.objects.get(pk=id) for id in form.cleaned_data['set_ids']]
 459
 460             for shelf in [shelf for shelf in old_shelves if shelf not in new_shelves]:
 461                 shelf.book_count = None
 462                 shelf.save()
 463
 464             for shelf in [shelf for shelf in new_shelves if shelf not in old_shelves]:
 465                 shelf.book_count = None
 466                 shelf.save()
 467
 468             book.tags = new_shelves + list(book.tags.filter(~Q(category='set') | ~Q(user=request.user)))
 469             if request.is_ajax():
 470                 return HttpResponse(_('<p>Shelves were sucessfully saved.</p>'))
 471             else:
 472                 return HttpResponseRedirect('/')
 473     else:
 474         form = forms.ObjectSetsForm(book, request.user)
 475         new_set_form = forms.NewSetForm()
 476
 477     return render_to_response('catalogue/book_sets.html', locals(),
 478         context_instance=RequestContext(request))
 479
 480
 481 @login_required
 482 @require_POST
 483 @cache.never_cache
 484 def remove_from_shelf(request, shelf, book):
 485     book = get_object_or_404(models.Book, slug=book)
 486     shelf = get_object_or_404(models.Tag, slug=shelf, category='set', user=request.user)
 487
 488     if shelf in book.tags:
 489         models.Tag.objects.remove_tag(book, shelf)
 490
 491         shelf.book_count = None
 492         shelf.save()
 493
 494         return HttpResponse(_('Book was successfully removed from the shelf'))
 495     else:
 496         return HttpResponse(_('This book is not on the shelf'))
 497
 498
 499 def collect_books(books):
 500     """
 501     Returns all real books in collection.
 502     """
 503     result = []
 504     for book in books:
 505         if len(book.children.all()) == 0:
 506             result.append(book)
 507         else:
 508             result += collect_books(book.children.all())
 509     return result
 510
 511
 512 @cache.never_cache
 513 def download_shelf(request, slug):
 514     """"
 515     Create a ZIP archive on disk and transmit it in chunks of 8KB,
 516     without loading the whole file into memory. A similar approach can
 517     be used for large dynamic PDF files.
 518     """
 519     shelf = get_object_or_404(models.Tag, slug=slug, category='set')
 520
 521     formats = []
 522     form = forms.DownloadFormatsForm(request.GET)
 523     if form.is_valid():
 524         formats = form.cleaned_data['formats']
 525     if len(formats) == 0:
 526         formats = ['pdf', 'epub', 'odt', 'txt', 'mp3', 'ogg']
 527
 528     # Create a ZIP archive
 529     temp = tempfile.TemporaryFile()
 530     archive = zipfile.ZipFile(temp, 'w')
 531
 532     already = set()
 533     for book in collect_books(models.Book.tagged.with_all(shelf)):
 534         if 'pdf' in formats and book.pdf_file:
 535             filename = book.pdf_file.path
 536             archive.write(filename, str('%s.pdf' % book.slug))
 537         if book.root_ancestor not in already and 'epub' in formats and book.root_ancestor.epub_file:
 538             filename = book.root_ancestor.epub_file.path
 539             archive.write(filename, str('%s.epub' % book.root_ancestor.slug))
 540             already.add(book.root_ancestor)
 541         if 'odt' in formats and book.odt_file:
 542             filename = book.odt_file.path
 543             archive.write(filename, str('%s.odt' % book.slug))
 544         if 'txt' in formats and book.txt_file:
 545             filename = book.txt_file.path
 546             archive.write(filename, str('%s.txt' % book.slug))
 547         if 'mp3' in formats and book.mp3_file:
 548             filename = book.mp3_file.path
 549             archive.write(filename, str('%s.mp3' % book.slug))
 550         if 'ogg' in formats and book.ogg_file:
 551             filename = book.ogg_file.path
 552             archive.write(filename, str('%s.ogg' % book.slug))
 553     archive.close()
 554
 555     response = HttpResponse(content_type='application/zip', mimetype='application/x-zip-compressed')
 556     response['Content-Disposition'] = 'attachment; filename=%s.zip' % shelf.sort_key
 557     response['Content-Length'] = temp.tell()
 558
 559     temp.seek(0)
 560     response.write(temp.read())
 561     return response
 562
 563
 564 @cache.never_cache
 565 def shelf_book_formats(request, shelf):
 566     """"
 567     Returns a list of formats of books in shelf.
 568     """
 569     shelf = get_object_or_404(models.Tag, slug=shelf, category='set')
 570
 571     formats = {'pdf': False, 'epub': False, 'odt': False, 'txt': False, 'mp3': False, 'ogg': False}
 572
 573     for book in collect_books(models.Book.tagged.with_all(shelf)):
 574         if book.pdf_file:
 575             formats['pdf'] = True
 576         if book.root_ancestor.epub_file:
 577             formats['epub'] = True
 578         if book.odt_file:
 579             formats['odt'] = True
 580         if book.txt_file:
 581             formats['txt'] = True
 582         if book.mp3_file:
 583             formats['mp3'] = True
 584         if book.ogg_file:
 585             formats['ogg'] = True
 586
 587     return HttpResponse(LazyEncoder().encode(formats))
 588
 589
 590 @login_required
 591 @require_POST
 592 @cache.never_cache
 593 def new_set(request):
 594     new_set_form = forms.NewSetForm(request.POST)
 595     if new_set_form.is_valid():
 596         new_set = new_set_form.save(request.user)
 597
 598         if request.is_ajax():
 599             return HttpResponse(_('<p>Shelf <strong>%s</strong> was successfully created</p>') % new_set)
 600         else:
 601             return HttpResponseRedirect('/')
 602
 603     return HttpResponseRedirect('/')
 604
 605
 606 @login_required
 607 @require_POST
 608 @cache.never_cache
 609 def delete_shelf(request, slug):
 610     user_set = get_object_or_404(models.Tag, slug=slug, category='set', user=request.user)
 611     user_set.delete()
 612
 613     if request.is_ajax():
 614         return HttpResponse(_('<p>Shelf <strong>%s</strong> was successfully removed</p>') % user_set.name)
 615     else:
 616         return HttpResponseRedirect('/')
 617
 618
 619 # ==================
 620 # = Authentication =
 621 # ==================
 622 @require_POST
 623 @cache.never_cache
 624 def login(request):
 625     form = AuthenticationForm(data=request.POST, prefix='login')
 626     if form.is_valid():
 627         auth.login(request, form.get_user())
 628         response_data = {'success': True, 'errors': {}}
 629     else:
 630         response_data = {'success': False, 'errors': form.errors}
 631     return HttpResponse(LazyEncoder(ensure_ascii=False).encode(response_data))
 632
 633
 634 @require_POST
 635 @cache.never_cache
 636 def register(request):
 637     registration_form = UserCreationForm(request.POST, prefix='registration')
 638     if registration_form.is_valid():
 639         user = registration_form.save()
 640         user = auth.authenticate(
 641             username=registration_form.cleaned_data['username'],
 642             password=registration_form.cleaned_data['password1']
 643         )
 644         auth.login(request, user)
 645         response_data = {'success': True, 'errors': {}}
 646     else:
 647         response_data = {'success': False, 'errors': registration_form.errors}
 648     return HttpResponse(LazyEncoder(ensure_ascii=False).encode(response_data))
 649
 650
 651 @cache.never_cache
 652 def logout_then_redirect(request):
 653     auth.logout(request)
 654     return HttpResponseRedirect(urlquote_plus(request.GET.get('next', '/'), safe='/?='))
 655
 656
 657
 658 # =========
 659 # = Admin =
 660 # =========
 661 @login_required
 662 @staff_required
 663 def import_book(request):
 664     """docstring for import_book"""
 665     book_import_form = forms.BookImportForm(request.POST, request.FILES)
 666     if book_import_form.is_valid():
 667         try:
 668             book_import_form.save()
 669         except:
 670             info = sys.exc_info()
 671             exception = pprint.pformat(info[1])
 672             tb = '\n'.join(traceback.format_tb(info[2]))
 673             return HttpResponse(_("An error occurred: %(exception)s\n\n%(tb)s") % {'exception':exception, 'tb':tb}, mimetype='text/plain')
 674         return HttpResponse(_("Book imported successfully"))
 675     else:
 676         return HttpResponse(_("Error importing file: %r") % book_import_form.errors)
 677
 678
 679
 680 def clock(request):
 681     """ Provides server time for jquery.countdown,
 682     in a format suitable for Date.parse()
 683     """
 684     from datetime import datetime
 685     return HttpResponse(datetime.now().strftime('%Y/%m/%d %H:%M:%S'))