Add per-post Image frontmatter and richer OG/article meta tags

Pass an optional Image field through PostMetadata -> Post -> PostWriter
so individual posts (especially link posts) can set their own og:image
instead of always falling back to the site-wide image. Also emit
article:published_time and article:tag for article pages, and switch
twitter:card to summary_large_image when a post-specific image is set.

lib/pressa/posts/metadata.rb

@@ -6,7 +6,7 @@ module Pressa
     class PostMetadata
       REQUIRED_FIELDS = %w[Title Author Date Timestamp].freeze
 
-      attr_reader :title, :author, :date, :formatted_date, :link, :tags
+      attr_reader :title, :author, :date, :formatted_date, :link, :tags, :image
 
       def initialize(yaml_hash)
         @raw = yaml_hash
@@ -39,6 +39,7 @@ module Pressa
         @formatted_date = @raw["Date"]
         @link = @raw["Link"]
         @tags = parse_tags(@raw["Tags"])
+        @image = @raw["Image"]
       end
 
       def parse_tags(value)

lib/pressa/posts/models.rb

@@ -11,6 +11,7 @@ module Pressa
       attribute :formatted_date, Types::String
       attribute :link, Types::String.optional.default(nil)
       attribute :tags, Types::Array.of(Types::String).default([].freeze)
+      attribute :image, Types::String.optional.default(nil)
       attribute :body, Types::String
       attribute :markdown_body, Types::String.default("".freeze)
       attribute :excerpt, Types::String

lib/pressa/posts/repo.rb

@@ -47,6 +47,7 @@ module Pressa
           formatted_date: metadata.formatted_date,
           link: metadata.link,
           tags: metadata.tags,
+          image: metadata.image,
           body: html_body,
           markdown_body: body_markdown,
           excerpt:,

lib/pressa/posts/writer.rb

@@ -117,7 +117,10 @@ module Pressa
           canonical_url: @site.url_for(post.path),
           content: content_view,
           page_description: post.excerpt,
-          page_type: "article"
+          page_type: "article",
+          page_image: post.image,
+          page_tags: post.tags,
+          page_published_time: post.date.iso8601
         )
 
         file_path = File.join(target_path, post.path.sub(/^\//, ""), "index.html")
@@ -161,7 +164,10 @@ module Pressa
         canonical_url:,
         content:,
         page_description: nil,
-        page_type: "website"
+        page_type: "website",
+        page_image: nil,
+        page_tags: [],
+        page_published_time: nil
       )
         layout = Views::Layout.new(
           site: @site,
@@ -169,6 +175,9 @@ module Pressa
           canonical_url:,
           page_description:,
           page_type:,
+          page_image:,
+          page_tags:,
+          page_published_time:,
           content:
         )
 

lib/pressa/views/layout.rb

@@ -8,6 +8,9 @@ module Pressa
         :page_subtitle,
         :page_description,
         :page_type,
+        :page_image,
+        :page_tags,
+        :page_published_time,
         :canonical_url,
         :page_scripts,
         :page_styles,
@@ -18,6 +21,9 @@ module Pressa
         canonical_url:, page_subtitle: nil,
         page_description: nil,
         page_type: "website",
+        page_image: nil,
+        page_tags: [],
+        page_published_time: nil,
         page_scripts: [],
         page_styles: [],
         content: nil
@@ -26,6 +32,9 @@ module Pressa
         @page_subtitle = page_subtitle
         @page_description = page_description
         @page_type = page_type
+        @page_image = page_image
+        @page_tags = page_tags
+        @page_published_time = page_published_time
         @canonical_url = canonical_url
         @page_scripts = page_scripts
         @page_styles = page_styles
@@ -54,7 +63,12 @@ module Pressa
             meta(property: "og:image", content: og_image_url) if og_image_url
             meta(property: "og:type", content: page_type)
             meta(property: "article:author", content: site.author)
-            meta(name: "twitter:card", content: "summary")
+            meta(name: "twitter:card", content: twitter_card_type)
+
+            if page_type == "article"
+              meta(property: "article:published_time", content: page_published_time) if page_published_time
+              page_tags.each { |tag| meta(property: "article:tag", content: tag) }
+            end
 
             link(
               rel: "alternate",
@@ -108,9 +122,18 @@ module Pressa
       end
 
       def og_image_url
+        if page_image
+          return page_image if page_image.start_with?("http://", "https://")
+          return absolute_asset(page_image)
+        end
+
         site.image_url
       end
 
+      def twitter_card_type
+        page_image ? "summary_large_image" : "summary"
+      end
+
       def all_styles
         site.styles + page_styles
       end

test/posts/metadata_test.rb

@@ -10,6 +10,7 @@ class Pressa::Posts::PostMetadataTest < Minitest::Test
       Timestamp: 2025-11-05T10:00:00-08:00
       Tags: Ruby, Testing
       Link: https://example.net/external
+      Image: /images/blog/test-post.png
       ---
 
       This is the post body.
@@ -25,6 +26,7 @@ class Pressa::Posts::PostMetadataTest < Minitest::Test
     assert_equal(5, metadata.date.day)
     assert_equal("https://example.net/external", metadata.link)
     assert_equal(["Ruby", "Testing"], metadata.tags)
+    assert_equal("/images/blog/test-post.png", metadata.image)
   end
 
   def test_parse_raises_error_when_required_fields_are_missing
@@ -56,6 +58,7 @@ class Pressa::Posts::PostMetadataTest < Minitest::Test
 
     assert_equal([], metadata.tags)
     assert_nil(metadata.link)
+    assert_nil(metadata.image)
   end
 
   def test_parse_raises_error_when_front_matter_is_missing

test/posts/writer_test.rb

@@ -23,7 +23,8 @@ class Pressa::Posts::PostWriterTest < Minitest::Test
         link: "https://example.net/linked",
         body: "<p>linked body</p>",
         excerpt: "linked body...",
-        path: "/posts/2025/11/link-post"
+        path: "/posts/2025/11/link-post",
+        image: "/images/blog/link-post.png"
       )
       regular_post = Pressa::Posts::Post.new(
         slug: "regular-post",
@@ -73,6 +74,22 @@ class Pressa::Posts::PostWriterTest < Minitest::Test
     end
   end
 
+  def test_write_posts_uses_post_image_for_og_image_and_article_tags
+    Dir.mktmpdir do |dir|
+      writer.write_posts(target_path: dir)
+
+      linked = File.join(dir, "posts/2025/11/link-post/index.html")
+      html = File.read(linked)
+
+      assert_includes(html, %(<meta property="og:image" content="https://samhuri.net/images/blog/link-post.png">))
+      assert_includes(html, %(<meta property="article:published_time" content="2025-11-05T10:00:00-08:00">))
+
+      regular = File.join(dir, "posts/2024/10/regular-post/index.html")
+      regular_html = File.read(regular)
+      assert_includes(regular_html, %(<meta property="article:tag" content="ruby">))
+    end
+  end
+
   def test_write_recent_posts_writes_index_page
     Dir.mktmpdir do |dir|
       writer.write_recent_posts(target_path: dir, limit: 1)

test/views/layout_test.rb

@@ -140,4 +140,66 @@ class Pressa::Views::LayoutTest < Minitest::Test
     refute_includes(html, "techhub.social")
     refute_includes(html, "github.com/samsonjs")
   end
+
+  def test_page_image_overrides_og_image_and_uses_large_image_card
+    html = Pressa::Views::Layout.new(
+      site:,
+      canonical_url: "https://samhuri.net/posts/",
+      page_image: "/images/blog/post.png",
+      content: content_view
+    ).call
+
+    assert_includes(html, %(<meta property="og:image" content="https://samhuri.net/images/blog/post.png">))
+    assert_includes(html, %(<meta name="twitter:card" content="summary_large_image">))
+  end
+
+  def test_page_image_preserves_absolute_urls
+    html = Pressa::Views::Layout.new(
+      site:,
+      canonical_url: "https://samhuri.net/posts/",
+      page_image: "https://cdn.example.net/preview.png",
+      content: content_view
+    ).call
+
+    assert_includes(html, %(<meta property="og:image" content="https://cdn.example.net/preview.png">))
+  end
+
+  def test_default_twitter_card_is_summary_without_page_image
+    html = Pressa::Views::Layout.new(
+      site:,
+      canonical_url: "https://samhuri.net/posts/",
+      content: content_view
+    ).call
+
+    assert_includes(html, %(<meta name="twitter:card" content="summary">))
+  end
+
+  def test_article_tags_render_published_time_and_tags
+    html = Pressa::Views::Layout.new(
+      site:,
+      canonical_url: "https://samhuri.net/posts/2025/11/05/post/",
+      page_type: "article",
+      page_published_time: "2025-11-05T10:00:00-08:00",
+      page_tags: ["ruby", "rails"],
+      content: content_view
+    ).call
+
+    assert_includes(html, %(<meta property="article:published_time" content="2025-11-05T10:00:00-08:00">))
+    assert_includes(html, %(<meta property="article:tag" content="ruby">))
+    assert_includes(html, %(<meta property="article:tag" content="rails">))
+  end
+
+  def test_article_tags_do_not_render_for_non_article_pages
+    html = Pressa::Views::Layout.new(
+      site:,
+      canonical_url: "https://samhuri.net/posts/",
+      page_type: "website",
+      page_published_time: "2025-11-05T10:00:00-08:00",
+      page_tags: ["ruby"],
+      content: content_view
+    ).call
+
+    refute_includes(html, "article:published_time")
+    refute_includes(html, "article:tag")
+  end
 end