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