#136 add cover_image and alt text fields for blog and use them if no …

…cover image for a post was set

cast/api/serializers.py

@@ -54,7 +54,8 @@ def get_show(self, _instance: Audio) -> dict:
         context = self.context.copy()
         if episode.cover_image is not None:
             context["cover_image_url"] = episode.cover_image.file.url
-        metadata["poster"] = episode.get_cover_image_url(context, podcast)
+        cover_image_context = episode.get_cover_image_context(context, podcast)
+        metadata["poster"] = cover_image_context["cover_image_url"]
         return metadata
 
     @staticmethod

cast/migrations/0058_add_cover_image_to_blog.py

@@ -0,0 +1,32 @@
+# Generated by Django 5.0.4 on 2024-06-12 16:10
+
+import django.db.models.deletion
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ("cast", "0057_rename_cover_image_and_add_alt_text"),
+        ("wagtailimages", "0025_alter_image_file_alter_rendition_file"),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name="blog",
+            name="cover_alt_text",
+            field=models.CharField(blank=True, default="", max_length=255),
+        ),
+        migrations.AddField(
+            model_name="blog",
+            name="cover_image",
+            field=models.ForeignKey(
+                blank=True,
+                help_text="An optional cover image.",
+                null=True,
+                on_delete=django.db.models.deletion.SET_NULL,
+                related_name="+",
+                to="wagtailimages.image",
+            ),
+        ),
+    ]

cast/models/index_pages.py

@@ -14,9 +14,10 @@
 from django.template.response import TemplateResponse
 from django.urls import reverse
 from django.utils.translation import gettext_lazy as _
-from wagtail.admin.panels import FieldPanel
+from wagtail.admin.panels import FieldPanel, MultiFieldPanel
 from wagtail.api import APIField
 from wagtail.fields import RichTextField
+from wagtail.images.models import Image
 from wagtail.models import Page, PageManager
 
 from cast import appsettings
@@ -53,6 +54,15 @@ class Blog(Page):
         default=True,
         help_text=_("Whether comments are enabled for this blog." ""),
     )
+    cover_image = models.ForeignKey(
+        Image,
+        help_text=_("An optional cover image."),
+        null=True,
+        blank=True,
+        on_delete=models.SET_NULL,
+        related_name="+",
+    )
+    cover_alt_text = models.CharField(max_length=255, blank=True, default="")
     noindex = models.BooleanField(
         "noindex",
         default=False,
@@ -79,6 +89,18 @@ class Blog(Page):
         FieldPanel("email"),
         FieldPanel("author"),
         FieldPanel("template_base_dir"),
+        MultiFieldPanel(
+            [
+                FieldPanel("cover_image"),
+                FieldPanel("cover_alt_text"),
+            ],
+            heading="Cover Image",
+            classname="collapsed",
+            help_text=_(
+                "The cover image for this post. It will be used in the feed, "
+                "in the twitter card and maybe on the blog index page."
+            ),
+        ),
     ]
     promote_panels = Page.promote_panels + [
         FieldPanel("noindex"),
@@ -242,8 +264,12 @@ def get_theme_form(self, next_path: str, template_base_dir: str) -> django.forms
             }
         )
 
-    def get_cover_image_url(self):
-        return ""
+    def get_cover_image_context(self) -> dict[str, str]:
+        context = {"cover_image_url": "", "cover_alt_text": ""}
+        if self.cover_image is not None:
+            context["cover_image_url"] = self.cover_image.file.url
+            context["cover_alt_text"] = self.cover_alt_text
+        return context
 
     @staticmethod
     def get_context_from_repository(context: ContextDict, repository: BlogIndexRepository) -> ContextDict:
@@ -348,10 +374,13 @@ def itunes_categories_parsed(self) -> dict[str, list[str]]:
         except json.decoder.JSONDecodeError:
             return {}
 
-    def get_cover_image_url(self):
-        if self.itunes_artwork is not None:
-            return self.itunes_artwork.original.url
-        return ""
+    def get_cover_image_context(self) -> dict[str, str]:
+        context = super().get_cover_image_context()
+        if context["cover_image_url"] == "":
+            # fallback to itunes artwork
+            if self.itunes_artwork is not None:
+                context["cover_image_url"] = self.itunes_artwork.original.url
+        return context
 
     def get_context(self, request: HtmxHttpRequest, *args, **kwargs) -> ContextDict:
         context = super().get_context(request, *args, **kwargs)

cast/models/pages.py

@@ -512,12 +512,15 @@ def podlove_players(self) -> list[tuple[str, str]]:
         return result
 
     @staticmethod
-    def get_cover_image_url(context: "ContextDict", blog: Optional["Blog"]) -> str:
-        if context.get("cover_image_url", ""):
-            return context["cover_image_url"]
+    def get_cover_image_context(context: "ContextDict", blog: Optional["Blog"]) -> dict[str, str]:
+        if (cover_image_url_from_post := context.get("cover_image_url")) is not None:
+            # if the cover image is set in the context, use it
+            return {"cover_image_url": cover_image_url_from_post, "cover_alt_text": context.get("cover_alt_text", "")}
         if blog is not None:
-            return blog.get_cover_image_url()
-        return ""
+            return blog.get_cover_image_context()
+
+        # no cover image set
+        return {"cover_image_url": "", "cover_alt_text": ""}
 
     def get_description(
         self,
@@ -680,7 +683,8 @@ def get_template(self, request: HttpRequest, *args, **kwargs) -> str:
     def get_context(self, request, **kwargs) -> "ContextDict":
         context = super().get_context(request, **kwargs)
         context["episode"] = self
-        context["cover_image_url"] = self.get_cover_image_url(context, self.podcast)
+        # context.update(self.get_cover_image_context(context, self.podcast))
+        context["cover_image_url"] = self.get_cover_image_context(context, self.podcast)
         context["cover_alt_text"] = self.cover_alt_text if self.cover_alt_text else "iTunes Artwork"
         if hasattr(request, "build_absolute_uri"):
             blog_slug = context["repository"].blog.slug

docs/episode.rst

@@ -13,8 +13,9 @@ In addition to the effect setting a cover image for a post has, setting a
 cover image for an episode will also be used as the episode's artwork in the
 podcast feed and in the Podlove Web Player.
 
-And if no cover image is set for the episode, the iTunes artwork of the podcast
-will be used as the episode's cover image / artwork.
+If no cover image is set for the episode, the blog’s cover image will be used.
+If the :ref:`blog <blog_overview>` does not have a cover image, the podcast’s
+iTunes artwork will be used as the episode’s cover image.
 
 Podcast Audio
 =============

docs/post.rst

@@ -20,7 +20,8 @@ The cover image for a post is used for meta tags like `twitter:image` or
 or the post detail page. If you set `cover_alt_text`, it can be used as the
 `alt` attribute of the cover image.
 
-For posts that don't have a cover image, I usually generate one using the
+For posts without a cover image, the :ref:`blog <blog_overview>`’s cover
+image will be used. Alternatively, I often generate one using the
 `shot-scraper <https://github.com/simonw/shot-scraper>`_ tool:
 
 .. code-block:: shell

tests/models_test.py

@@ -138,8 +138,31 @@ def test_get_django_repository(self, blog, simple_request, use_django_blog_index
         repository = blog.get_repository(simple_request, {})
         assert isinstance(repository, BlogIndexRepository)
 
-    def test_get_cover_image_url_for_blog(self):
-        assert "" == Blog(id=1).get_cover_image_url()
+    def test_get_cover_image_url_for_blog(self, mocker):
+        # just empty cover image
+        blog = Blog(id=1)
+        assert blog.get_cover_image_context() == {"cover_image_url": "", "cover_alt_text": ""}
+
+        # cover image via blog.cover_image - using mock object because of the ImageField setter
+        mock_image = mocker.MagicMock()
+        mock_image.file.url = "https://example.org/cover.jpg"
+        mocker.patch("cast.models.Blog.cover_image", mock_image)
+        assert blog.get_cover_image_context() == {
+            "cover_image_url": "https://example.org/cover.jpg",
+            "cover_alt_text": "",
+        }
+
+
+class TestPodcastModel:
+    def test_cover_image_from_super(self, mocker):
+        podcast = Podcast(id=1)
+        mocker_image = mocker.MagicMock()
+        mocker_image.file.url = "https://example.org/cover.jpg"
+        mocker.patch("cast.models.Blog.cover_image", mocker_image)
+        assert podcast.get_cover_image_context() == {
+            "cover_image_url": "https://example.org/cover.jpg",
+            "cover_alt_text": "",
+        }
 
 
 class TestPostModel:
@@ -357,14 +380,15 @@ def test_get_updated_timestamp(self):
         post.last_published_at = timezone.now()
         assert post.get_updated_timestamp() == int(post.last_published_at.timestamp())
 
-    def test_get_cover_image_url(self):
+    def test_get_cover_image_context(self):
         post = Post(id=1)  #
         # no cover_image
-        cover_image_url = post.get_cover_image_url({}, None)
-        assert cover_image_url == ""
+        context = post.get_cover_image_context({}, None)
+        assert context == {"cover_alt_text": "", "cover_image_url": ""}
 
         # test return early, because episode.cover_image was set
-        cover_image_url = post.get_cover_image_url({"cover_image_url": "https://example.org/cover.jpg"}, None)
+        context = post.get_cover_image_context({"cover_image_url": "https://example.org/cover.jpg"}, None)
+        cover_image_url = context["cover_image_url"]
         assert cover_image_url == "https://example.org/cover.jpg"
 
         # get cover image from iTunes artwork
@@ -376,7 +400,8 @@ class Original:
         artwork = ItunesArtWork(original=Original())
         podcast = Podcast(id=1, itunes_artwork=artwork)
 
-        cover_image_url = post.get_cover_image_url({}, podcast)
+        context = post.get_cover_image_context({}, podcast)
+        cover_image_url = context["cover_image_url"]
         assert cover_image_url == "https://example.org/itunes.jpg"