Merge remote-tracking branch 'upstream/pull/4882'

app/controllers/diary_entries_controller.rb

@@ -68,6 +68,7 @@ def show
     @entry = entries.find_by(:id => params[:id])
     if @entry
       @title = t ".title", :user => params[:display_name], :title => @entry.title
+      @og_image = @entry.body.image
       @comments = can?(:unhidecomment, DiaryEntry) ? @entry.comments : @entry.visible_comments
     else
       @title = t "diary_entries.no_such_entry.title", :id => params[:id]

app/helpers/open_graph_helper.rb

@@ -1,10 +1,10 @@
 module OpenGraphHelper
-  def opengraph_tags(title = nil)
+  def opengraph_tags(title = nil, og_image = nil)
     tags = {
       "og:site_name" => t("layouts.project_name.title"),
       "og:title" => [title, t("layouts.project_name.title")].compact.join(" | "),
       "og:type" => "website",
-      "og:image" => image_url("osm_logo_256.png"),
+      "og:image" => og_image ? URI.join(root_url, og_image) : image_url("osm_logo_256.png"),
       "og:url" => url_for(:only_path => false),
       "og:description" => t("layouts.intro_text")
     }

app/models/diary_entry.rb

@@ -50,7 +50,7 @@ class DiaryEntry < ApplicationRecord
   after_save :spam_check
 
   def body
-    RichText.new(self[:body_format], self[:body])
+    @body ||= RichText.new(self[:body_format], self[:body])
   end
 
   private

app/views/layouts/_meta.html.erb

@@ -21,7 +21,7 @@
 <% end -%>
 <%= tag.link :rel => "search", :type => "application/opensearchdescription+xml", :title => "OpenStreetMap Search", :href => asset_path("osm.xml") %>
 <%= tag.meta :name => "description", :content => "OpenStreetMap is the free wiki world map." %>
-<%= opengraph_tags(@title) %>
+<%= opengraph_tags(@title, @og_image) %>
 <% if flash[:matomo_goal] -%>
 <%= tag.meta :name => "matomo-goal", :content => flash[:matomo_goal] %>
 <% end -%>

lib/rich_text.rb

@@ -49,6 +49,10 @@ def spam_score
         (spammy_phrases * 40)
     end
 
+    def image
+      nil
+    end
+
     protected
 
     def simple_format(text)
@@ -80,12 +84,33 @@ def to_text
 
   class Markdown < Base
     def to_html
-      linkify(sanitize(Kramdown::Document.new(self).to_html), :all)
+      linkify(sanitize(document.to_html), :all)
     end
 
     def to_text
       to_s
     end
+
+    def image
+      return @image if defined? @image
+
+      @image = first_image_element(document.root)&.attr&.[]("src")
+    end
+
+    private
+
+    def document
+      @document ||= Kramdown::Document.new(self)
+    end
+
+    def first_image_element(element)
+      return element if element.type == :img
+
+      element.children.find do |child|
+        nested_image = first_image_element(child)
+        break nested_image if nested_image
+      end
+    end
   end
 
   class Text < Base

test/controllers/diary_entries_controller_test.rb

@@ -752,6 +752,28 @@ def test_show_hidden_comments
     end
   end
 
+  def test_show_og_image
+    user = create(:user)
+    diary_entry = create(:diary_entry, :user => user, :body => "![some picture](https://example.com/picture.jpg)")
+
+    get diary_entry_path(user, diary_entry)
+    assert_response :success
+    assert_dom "head meta[property='og:image']" do
+      assert_dom "> @content", "https://example.com/picture.jpg"
+    end
+  end
+
+  def test_show_og_image_with_relative_uri
+    user = create(:user)
+    diary_entry = create(:diary_entry, :user => user, :body => "![some local picture](/picture.jpg)")
+
+    get diary_entry_path(user, diary_entry)
+    assert_response :success
+    assert_dom "head meta[property='og:image']" do
+      assert_dom "> @content", "#{root_url}picture.jpg"
+    end
+  end
+
   def test_hide
     user = create(:user)
     diary_entry = create(:diary_entry, :user => user)

test/lib/rich_text_test.rb

@@ -250,6 +250,31 @@ def test_text_spam_score
     assert_equal 141, r.spam_score.round
   end
 
+  def test_text_no_image
+    r = RichText.new("text", "foo https://example.com/ bar")
+    assert_nil r.image
+  end
+
+  def test_html_no_image
+    r = RichText.new("html", "foo <a href='https://example.com/'>bar</a> baz")
+    assert_nil r.image
+  end
+
+  def test_markdown_no_image
+    r = RichText.new("markdown", "foo [bar](https://example.com/) baz")
+    assert_nil r.image
+  end
+
+  def test_markdown_image
+    r = RichText.new("markdown", "foo ![bar](https://example.com/image.jpg) baz")
+    assert_equal "https://example.com/image.jpg", r.image
+  end
+
+  def test_markdown_first_image
+    r = RichText.new("markdown", "foo ![bar1](https://example.com/image1.jpg) baz\nfoo ![bar2](https://example.com/image2.jpg) baz")
+    assert_equal "https://example.com/image1.jpg", r.image
+  end
+
   private
 
   def assert_html(richtext, &block)