fix parent PDF creation, add test
[wolnelektury.git] / apps / api / handlers.py
index a4782dc..9bb8900 100644 (file)
 # This file is part of Wolnelektury, licensed under GNU Affero GPLv3 or later.
 # Copyright © Fundacja Nowoczesna Polska. See NOTICE for more information.
 
-from datetime import datetime
-from piston.handler import BaseHandler
+from datetime import datetime, timedelta
+import json
+
+from django.conf import settings
+from django.contrib.sites.models import Site
+from django.core.urlresolvers import reverse
+from piston.handler import AnonymousBaseHandler, BaseHandler
+from piston.utils import rc
 
 from api.helpers import timestamp
 from api.models import Deleted
-from catalogue.models import Book, Tag
+from catalogue.forms import BookImportForm
+from catalogue.models import Book, Tag, BookMedia, Fragment
+
+
+API_BASE = WL_BASE = MEDIA_BASE = 'http://' + Site.objects.get_current().domain
+
+
+category_singular = {
+    'authors': 'author',
+    'kinds': 'kind',
+    'genres': 'genre',
+    'epochs': 'epoch',
+    'themes': 'theme',
+    'books': 'book',
+}
+category_plural={}
+for k, v in category_singular.items():
+    category_plural[v] = k
+
+
+def read_tags(tags, allowed):
+    """ Reads a path of filtering tags.
+
+    :param str tags: a path of category and slug pairs, like: authors/an-author/...
+    :returns: list of Tag objects
+    :raises: ValueError when tags can't be found
+    """
+    if not tags:
+        return []
+
+    tags = tags.strip('/').split('/')
+    real_tags = []
+    while tags:
+        category = tags.pop(0)
+        slug = tags.pop(0)
+
+        try:
+            category = category_singular[category]
+        except KeyError:
+            raise ValueError('Unknown category.')
+
+        if not category in allowed:
+            raise ValueError('Category not allowed.')
+
+        # !^%@#$^#!
+        if category == 'book':
+            slug = 'l-' + slug
+
+        try:
+            real_tags.append(Tag.objects.get(category=category, slug=slug))
+        except Tag.DoesNotExist:
+            raise ValueError('Tag not found')
+    return real_tags
+
+
+# RESTful handlers
+
+
+class BookMediaHandler(BaseHandler):
+    """ Responsible for representing media in Books. """
+
+    model = BookMedia
+    fields = ['name', 'type', 'url']
+
+    @classmethod
+    def url(cls, media):
+        """ Link to media on site. """
+
+        return MEDIA_BASE + media.file.url
+
+
+class BookDetailHandler(BaseHandler):
+    """ Main handler for Book objects.
+
+    Responsible for lists of Book objects
+    and fields used for representing Books.
+
+    """
+    allowed_methods = ['GET']
+    fields = ['title', 'parent',
+        'xml', 'html', 'pdf', 'epub', 'txt',
+        'media', 'url'] + category_singular.keys()
+
+    def read(self, request, slug):
+        """ Returns details of a book, identified by a slug. """
+
+        try:
+            return Book.objects.get(slug=slug)
+        except Book.DoesNotExist:
+            return rc.NOT_FOUND
+
+
+class AnonymousBooksHandler(AnonymousBaseHandler):
+    """ Main handler for Book objects.
+
+    Responsible for lists of Book objects
+    and fields used for representing Books.
+
+    """
+    allowed_methods = ('GET',)
+    model = Book
+    fields = ['href', 'title']
+
+    categories = set(['author', 'epoch', 'kind', 'genre'])
+
+    @classmethod
+    def href(cls, book):
+        """ Returns an URI for a Book in the API. """
+        return API_BASE + reverse("api_book", args=[book.slug])
+
+    @classmethod
+    def url(cls, book):
+        """ Returns Book's URL on the site. """
+
+        return WL_BASE + book.get_absolute_url()
+
+    def read(self, request, tags, top_level=False):
+        """ Lists all books with given tags.
+
+        :param tags: filtering tags; should be a path of categories
+             and slugs, i.e.: authors/an-author/epoch/an-epoch/
+        :param top_level: if True and a book is included in the results,
+             it's children are aren't. By default all books matching the tags
+             are returned.
+        """
+        tags = read_tags(tags, allowed=self.categories)
+        if tags:
+            if top_level:
+                books = Book.tagged_top_level(tags)
+                return books if books else rc.NOT_FOUND
+            else:
+                books = Book.tagged.with_all(tags)
+        else:
+            books = Book.objects.all()
+
+        if books.exists():
+            return books
+        else:
+            return rc.NOT_FOUND
+
+    def create(self, request, tags, top_level=False):
+        return 'aaa'
+
+    @classmethod
+    def media(self, book):
+        """ Returns all media for a book. """
+
+        return book.media.all()
+
+
+class BooksHandler(BaseHandler):
+    model = Book
+    fields = ('slug', 'title')
+    anonymous = AnonymousBooksHandler
+
+    def create(self, request, tags, top_level=False):
+        if not request.user.has_perm('catalogue.add_book'):
+            return rc.FORBIDDEN
+
+        data = json.loads(request.POST.get('data'))
+        form = BookImportForm(data)
+        if form.is_valid():
+            form.save()
+            return rc.CREATED
+        else:
+            return rc.NOT_FOUND
+
+# add categorized tags fields for Book
+def _tags_getter(category):
+    @classmethod
+    def get_tags(cls, book):
+        return book.tags.filter(category=category)
+    return get_tags
+for plural, singular in category_singular.items():
+    setattr(BooksHandler, plural, _tags_getter(singular))
+
+# add fields for files in Book
+def _file_getter(format):
+    field = "%s_file" % format
+    @classmethod
+    def get_file(cls, book):
+        f = getattr(book, field)
+        if f:
+            return MEDIA_BASE + f.url
+        else:
+            return ''
+    return get_file
+for format in ('xml', 'txt', 'html', 'epub', 'pdf'):
+    setattr(BooksHandler, format, _file_getter(format))
+
+
+class TagDetailHandler(BaseHandler):
+    """ Responsible for details of a single Tag object. """
+
+    fields = ['name', 'sort_key', 'description']
+
+    def read(self, request, category, slug):
+        """ Returns details of a tag, identified by category and slug. """
+
+        try:
+            category_sng = category_singular[category]
+        except KeyError, e:
+            return rc.NOT_FOUND
+
+        try:
+            return Tag.objects.get(category=category_sng, slug=slug)
+        except Tag.DoesNotExist:
+            return rc.NOT_FOUND
+
+
+class TagsHandler(BaseHandler):
+    """ Main handler for Tag objects.
+
+    Responsible for lists of Tag objects
+    and fields used for representing Tags.
+
+    """
+    allowed_methods = ('GET',)
+    model = Tag
+    fields = ['name', 'href']
+
+    def read(self, request, category):
+        """ Lists all tags in the category (eg. all themes). """
+
+        try:
+            category_sng = category_singular[category]
+        except KeyError, e:
+            return rc.NOT_FOUND
+
+        tags = Tag.objects.filter(category=category_sng)
+        tags = [t for t in tags if t.get_count() > 0]
+        if tags:
+            return tags
+        else:
+            return rc.NOT_FOUND
+
+
+    @classmethod
+    def href(cls, tag):
+        """ Returns URI in the API for the tag. """
+
+        return API_BASE + reverse("api_tag", args=[category_plural[tag.category], tag.slug])
+
+
+class FragmentDetailHandler(BaseHandler):
+    fields = ['book', 'anchor', 'text', 'url', 'themes']
+
+    def read(self, request, slug, anchor):
+        """ Returns details of a fragment, identified by book slug and anchor. """
+
+        try:
+            return Fragment.objects.get(book__slug=slug, anchor=anchor)
+        except Fragment.DoesNotExist:
+            return rc.NOT_FOUND
+
+
+class FragmentsHandler(BaseHandler):
+    """ Main handler for Fragments.
+
+    Responsible for lists of Fragment objects
+    and fields used for representing Fragments.
+
+    """
+    model = Fragment
+    fields = ['book', 'anchor', 'href']
+    allowed_methods = ('GET',)
+
+    categories = set(['author', 'epoch', 'kind', 'genre', 'book', 'theme'])
+
+    def read(self, request, tags):
+        """ Lists all fragments with given book, tags, themes.
+
+        :param tags: should be a path of categories and slugs, i.e.:
+             books/book-slug/authors/an-author/themes/a-theme/
+
+        """
+        tags = read_tags(tags, allowed=self.categories)
+        fragments = Fragment.tagged.with_all(tags).select_related('book')
+        if fragments.exists():
+            return fragments
+        else:
+            return rc.NOT_FOUND
+
+    @classmethod
+    def href(cls, fragment):
+        """ Returns URI in the API for the fragment. """
+
+        return API_BASE + reverse("api_fragment", args=[fragment.book.slug, fragment.anchor])
+
+    @classmethod
+    def url(cls, fragment):
+        """ Returns URL on the site for the fragment. """
+
+        return WL_BASE + fragment.get_absolute_url()
+
+    @classmethod
+    def themes(cls, fragment):
+        """ Returns a list of theme tags for the fragment. """
+
+        return fragment.tags.filter(category='theme')
+
+
+
+
+# Changes handlers
 
 class CatalogueHandler(BaseHandler):
 
@@ -16,6 +326,24 @@ class CatalogueHandler(BaseHandler):
         fields_str = request.GET.get(name) if request is not None else None
         return fields_str.split(',') if fields_str is not None else None
 
+    @staticmethod
+    def until(t=None):
+        """ Returns time suitable for use as upper time boundary for check.
+
+            Used to avoid issues with time between setting the change stamp
+            and actually saving the model in database.
+            Cuts the microsecond part to avoid issues with DBs where time has
+            more precision.
+
+            :param datetime t: manually sets the upper boundary
+
+        """
+        # set to five minutes ago, to avoid concurrency issues
+        if t is None:
+            t = datetime.now() - timedelta(seconds=settings.API_WAIT)
+        # set to whole second in case DB supports something smaller
+        return t.replace(microsecond=0)
+
     @staticmethod
     def book_dict(book, fields=None):
         all_fields = ('url', 'title', 'description',
@@ -26,6 +354,7 @@ class CatalogueHandler(BaseHandler):
                       'tags',
                       'license', 'license_description', 'source_name',
                       'technical_editors', 'editors',
+                      'author', 'sort_key',
                      )
         if fields:
             fields = (f for f in fields if f in all_fields)
@@ -47,9 +376,9 @@ class CatalogueHandler(BaseHandler):
 
             elif field in ('mp3', 'ogg', 'daisy'):
                 media = []
-                for m in book.medias.filter(type=''):
-                    files.append({
-                        'url': m.file.get_absolute_url(),
+                for m in book.media.filter(type=field):
+                    media.append({
+                        'url': m.file.url,
                         'size': m.file.size,
                     })
                 if media:
@@ -61,6 +390,12 @@ class CatalogueHandler(BaseHandler):
             elif field == 'tags':
                 obj[field] = [t.id for t in book.tags.exclude(category__in=('book', 'set'))]
 
+            elif field == 'author':
+                obj[field] = ", ".join(t.name for t in book.tags.filter(category='author'))
+
+            elif field == 'parent':
+                obj[field] = book.parent_id
+
             elif field in ('license', 'license_description', 'source_name',
                       'technical_editors', 'editors'):
                 f = extra_info.get(field)
@@ -76,8 +411,14 @@ class CatalogueHandler(BaseHandler):
         return obj
 
     @classmethod
-    def book_changes(cls, since=0, request=None, fields=None):
+    def book_changes(cls, request=None, since=0, until=None, fields=None):
         since = datetime.fromtimestamp(int(since))
+        until = cls.until(until)
+
+        changes = {
+            'time_checked': timestamp(until)
+        }
+
         if not fields:
             fields = cls.fields(request, 'book_fields')
 
@@ -86,19 +427,28 @@ class CatalogueHandler(BaseHandler):
         deleted = []
 
         last_change = since
-        for book in Book.objects.filter(changed_at__gte=since):
+        for book in Book.objects.filter(changed_at__gte=since,
+                    changed_at__lt=until):
             book_d = cls.book_dict(book, fields)
             updated.append(book_d)
+        if updated:
+            changes['updated'] = updated
 
-        for book in Deleted.objects.filter(content_type=Book, deleted_at__gte=since, created_at__lt=since):
+        for book in Deleted.objects.filter(content_type=Book, 
+                    deleted_at__gte=since,
+                    deleted_at__lt=until,
+                    created_at__lt=since):
             deleted.append(book.id)
-        return {'updated': updated, 'deleted': deleted}
+        if deleted:
+            changes['deleted'] = deleted
+
+        return changes
 
     @staticmethod
     def tag_dict(tag, fields=None):
         all_fields = ('name', 'category', 'sort_key', 'description',
                       'gazeta_link', 'wiki_link',
-                      'url',
+                      'url', 'books',
                      )
 
         if fields:
@@ -112,6 +462,12 @@ class CatalogueHandler(BaseHandler):
             if field == 'url':
                 obj[field] = tag.get_absolute_url()
 
+            elif field == 'books':
+                obj[field] = [b.id for b in Book.tagged_top_level([tag])]
+
+            elif field == 'sort_key':
+                obj[field] = tag.sort_key
+
             else:
                 f = getattr(tag, field)
                 if f:
@@ -121,14 +477,20 @@ class CatalogueHandler(BaseHandler):
         return obj
 
     @classmethod
-    def tag_changes(cls, since=0, request=None, fields=None, categories=None):
+    def tag_changes(cls, request=None, since=0, until=None, fields=None, categories=None):
         since = datetime.fromtimestamp(int(since))
+        until = cls.until(until)
+
+        changes = {
+            'time_checked': timestamp(until)
+        }
+
         if not fields:
             fields = cls.fields(request, 'tag_fields')
         if not categories:
             categories = cls.fields(request, 'tag_categories')
 
-        all_categories = ('author', 'theme', 'epoch', 'kind', 'genre')
+        all_categories = ('author', 'epoch', 'kind', 'genre')
         if categories:
             categories = (c for c in categories if c in all_categories)
         else:
@@ -137,29 +499,47 @@ class CatalogueHandler(BaseHandler):
         updated = []
         deleted = []
 
-        for tag in Tag.objects.filter(category__in=categories, changed_at__gte=since):
-            tag_d = cls.tag_dict(tag, fields)
-            updated.append(tag_d)
+        for tag in Tag.objects.filter(category__in=categories, 
+                    changed_at__gte=since,
+                    changed_at__lt=until):
+            # only serve non-empty tags
+            if tag.get_count():
+                tag_d = cls.tag_dict(tag, fields)
+                updated.append(tag_d)
+            elif tag.created_at < since:
+                deleted.append(tag.id)
+        if updated:
+            changes['updated'] = updated
 
         for tag in Deleted.objects.filter(category__in=categories,
-                content_type=Tag, deleted_at__gte=since, created_at__lt=since):
+                content_type=Tag, 
+                    deleted_at__gte=since,
+                    deleted_at__lt=until,
+                    created_at__lt=since):
             deleted.append(tag.id)
-        return {'updated': updated, 'deleted': deleted}
+        if deleted:
+            changes['deleted'] = deleted
+
+        return changes
 
     @classmethod
-    def changes(cls, since=0, request=None, book_fields=None,
+    def changes(cls, request=None, since=0, until=None, book_fields=None,
                 tag_fields=None, tag_categories=None):
+        until = cls.until(until)
+
         changes = {
-            'time_checked': timestamp(datetime.now())
+            'time_checked': timestamp(until)
         }
 
         changes_by_type = {
-            'books': cls.book_changes(since, request, book_fields),
-            'tags': cls.tag_changes(since, request, tag_fields, tag_categories),
+            'books': cls.book_changes(request, since, until, book_fields),
+            'tags': cls.tag_changes(request, since, until, tag_fields, tag_categories),
         }
 
         for model in changes_by_type:
             for field in changes_by_type[model]:
+                if field == 'time_checked':
+                    continue
                 changes.setdefault(field, {})[model] = changes_by_type[model][field]
         return changes
 
@@ -168,18 +548,18 @@ class BookChangesHandler(CatalogueHandler):
     allowed_methods = ('GET',)
 
     def read(self, request, since):
-        return self.book_changes(since, request)
+        return self.book_changes(request, since)
 
 
 class TagChangesHandler(CatalogueHandler):
     allowed_methods = ('GET',)
 
     def read(self, request, since):
-        return self.tag_changes(since, request)
+        return self.tag_changes(request, since)
 
 
 class ChangesHandler(CatalogueHandler):
     allowed_methods = ('GET',)
 
     def read(self, request, since):
-        return self.changes(since, request)
+        return self.changes(request, since)