Merge pull request #402 from mouse-reeve/alt-text

Federate cover alt text

bookwyrm/models/book.py

@@ -52,12 +52,29 @@ class Book(ActivitypubMixin, BookWyrmModel):
     authors = fields.ManyToManyField('Author')
     # preformatted authorship string for search and easier display
     author_text = models.CharField(max_length=255, blank=True, null=True)
-    cover = fields.ImageField(upload_to='covers/', blank=True, null=True)
+    cover = fields.ImageField(
+        upload_to='covers/', blank=True, null=True, alt_field='alt_text')
     first_published_date = fields.DateTimeField(blank=True, null=True)
     published_date = fields.DateTimeField(blank=True, null=True)
 
     objects = InheritanceManager()
 
+    @property
+    def edition_info(self):
+        ''' properties of this edition, as a string '''
+        items = [
+            self.physical_format,
+            self.languages[0] + ' language' if self.languages and \
+                    self.languages[0] != 'English' else None,
+            str(self.published_date.year) if self.published_date else None,
+        ]
+        return ', '.join(i for i in items if i)
+
+    @property
+    def alt_text(self):
+        ''' image alt test '''
+        return '%s cover (%s)' % (self.title, self.edition_info)
+
     def save(self, *args, **kwargs):
         ''' can't be abstract for query reasons, but you shouldn't USE it '''
         if not isinstance(self, Edition) and not isinstance(self, Work):

bookwyrm/models/fields.py

@@ -305,18 +305,22 @@ class TagField(ManyToManyField):
         return items
 
 
-def image_serializer(value):
+def image_serializer(value, alt):
     ''' helper for serializing images '''
     if value and hasattr(value, 'url'):
         url = value.url
     else:
         return None
     url = 'https://%s%s' % (DOMAIN, url)
-    return activitypub.Image(url=url)
+    return activitypub.Image(url=url, name=alt)
 
 
 class ImageField(ActivitypubFieldMixin, models.ImageField):
     ''' activitypub-aware image field '''
+    def __init__(self, *args, alt_field=None, **kwargs):
+        self.alt_field = alt_field
+        super().__init__(*args, **kwargs)
+
     # pylint: disable=arguments-differ
     def set_field_from_activity(self, instance, data, save=True):
         ''' helper function for assinging a value to the field '''
@@ -326,9 +330,19 @@ class ImageField(ActivitypubFieldMixin, models.ImageField):
             return
         getattr(instance, self.name).save(*formatted, save=save)
 
+    def set_activity_from_field(self, activity, instance):
+        value = getattr(instance, self.name)
+        if value is None:
+            return
+        alt_text = getattr(instance, self.alt_field)
+        formatted = self.field_to_activity(value, alt_text)
 
-    def field_to_activity(self, value):
-        return image_serializer(value)
+        key = self.get_activitypub_field()
+        activity[key] = formatted
+
+
+    def field_to_activity(self, value, alt=None):
+        return image_serializer(value, alt)
 
 
     def field_from_activity(self, value):

bookwyrm/models/status.py

@@ -86,11 +86,11 @@ class Status(OrderedCollectionPageMixin, BookWyrmModel):
                 activity['name'] = self.pure_name
             activity['type'] = self.pure_type
             activity['attachment'] = [
-                image_serializer(b.cover) for b in self.mention_books.all() \
-                        if b.cover]
+                image_serializer(b.cover, b.alt_text) \
+                    for b in self.mention_books.all()[:4] if b.cover]
             if hasattr(self, 'book'):
                 activity['attachment'].append(
-                    image_serializer(self.book.cover)
+                    image_serializer(self.book.cover, self.book.alt_text)
                 )
         return activity
 

bookwyrm/models/user.py

@@ -53,7 +53,8 @@ class User(OrderedCollectionPageMixin, AbstractUser):
     # name is your display name, which you can change at will
     name = fields.CharField(max_length=100, default='')
     avatar = fields.ImageField(
-        upload_to='avatars/', blank=True, null=True, activitypub_field='icon')
+        upload_to='avatars/', blank=True, null=True,
+        activitypub_field='icon', alt_field='alt_text')
     followers = fields.ManyToManyField(
         'self',
         link_only=True,
@@ -90,6 +91,11 @@ class User(OrderedCollectionPageMixin, AbstractUser):
     last_active_date = models.DateTimeField(auto_now=True)
     manually_approves_followers = fields.BooleanField(default=False)
 
+    @property
+    def alt_text(self):
+        ''' alt text with username '''
+        return 'avatar for %s' % (self.localname or self.username)
+
     @property
     def display_name(self):
         ''' show the cleanest version of the user's name possible '''