+ def urlid(self, sep='/'):
+ stem = self.slug
+ if self.language != settings.CATALOGUE_DEFAULT_LANGUAGE:
+ stem += sep + self.language
+ return stem
+
+ def fileid(self):
+ return self.urlid('_')
+
+ @staticmethod
+ def split_urlid(urlid, sep='/', default_lang=settings.CATALOGUE_DEFAULT_LANGUAGE):
+ """Splits a URL book id into slug and language code.
+
+ Returns a dictionary usable i.e. for object lookup, or None.
+
+ >>> Book.split_urlid("a-slug/pol", default_lang="eng")
+ {'slug': 'a-slug', 'language': 'pol'}
+ >>> Book.split_urlid("a-slug", default_lang="eng")
+ {'slug': 'a-slug', 'language': 'eng'}
+ >>> Book.split_urlid("a-slug_pol", "_", default_lang="eng")
+ {'slug': 'a-slug', 'language': 'pol'}
+ >>> Book.split_urlid("a-slug/eng", default_lang="eng")
+
+ """
+ parts = urlid.rsplit(sep, 1)
+ if len(parts) == 2:
+ if parts[1] == default_lang:
+ return None
+ return {'slug': parts[0], 'language': parts[1]}
+ else:
+ return {'slug': urlid, 'language': default_lang}
+
+ @classmethod
+ def split_fileid(cls, fileid):
+ return cls.split_urlid(fileid, '_')
+