twitter: fix preview_urls when source url is a direct image.

Fix preview_urls returning an empty array when the source url is a
direct image from Twitter.

Also return preview_urls in /source.json.

app/logical/sources/strategies/base.rb

@@ -269,6 +269,8 @@ module Sources
           :artists => artists.as_json(include: :sorted_urls),
           :image_url => image_url,
           :image_urls => image_urls,
+          :preview_url => preview_url,
+          :preview_urls => preview_urls,
           :page_url => page_url,
           :canonical_url => canonical_url,
           :normalized_for_artist_finder_url => normalize_for_artist_finder,

app/logical/sources/strategies/twitter.rb

@@ -80,10 +80,14 @@ module Sources::Strategies
     end
 
     def preview_urls
-      return image_urls if api_response.blank?
+      if api_response.dig(:extended_entities, :media).present?
-
+        api_response.dig(:extended_entities, :media).to_a.map do |media|
-      api_response.dig(:extended_entities, :media).to_a.map do |media|
+          media[:media_url_https] + ":small"
-        media[:media_url_https] + ":small"
+        end
+      else
+        image_urls.map do |url|
+          url.gsub(/:orig\z/, ":small")
+        end
       end
     end
 

test/unit/sources/twitter_test.rb

@@ -76,6 +76,7 @@ module Sources
 
       should "get the urls" do
         assert_equal("https://pbs.twimg.com/media/B7jfc1JCcAEyeJh.png:orig", @site.image_url)
+        assert_equal("https://pbs.twimg.com/media/B7jfc1JCcAEyeJh.png:small", @site.preview_url)
         assert_equal("https://twitter.com/Strangestone/status/556440271961858051", @site.page_url)
         assert_equal("https://twitter.com/Strangestone/status/556440271961858051", @site.canonical_url)
       end
@@ -108,8 +109,9 @@ module Sources
         assert_equal("nounproject", @site.artist_name)
       end
 
-      should "get the image url" do
+      should "get the image urls" do
         assert_equal("https://pbs.twimg.com/media/B4HSEP5CUAA4xyu.png:orig", @site.image_url)
+        assert_equal("https://pbs.twimg.com/media/B4HSEP5CUAA4xyu.png:small", @site.preview_url)
       end
 
       should "get the canonical url" do
@@ -136,12 +138,10 @@ module Sources
         @site = Sources::Strategies.find("https://pbs.twimg.com/media/B4HSEP5CUAA4xyu.png:large", "https://twitter.com/nounproject/status/540944400767922176")
       end
 
-      should "get the artist name" do
+      should "get the source data" do
         assert_equal("nounproject", @site.artist_name)
-      end
-
-      should "get the image url" do
         assert_equal("https://pbs.twimg.com/media/B4HSEP5CUAA4xyu.png:orig", @site.image_url)
+        assert_equal("https://pbs.twimg.com/media/B4HSEP5CUAA4xyu.png:small", @site.preview_url)
       end
     end
 
@@ -153,6 +153,8 @@ module Sources
       should "work" do
         assert_equal("https://pbs.twimg.com/media/B4HSEP5CUAA4xyu.png:orig", @site.image_url)
         assert_equal(["https://pbs.twimg.com/media/B4HSEP5CUAA4xyu.png:orig"], @site.image_urls)
+        assert_equal("https://pbs.twimg.com/media/B4HSEP5CUAA4xyu.png:small", @site.preview_url)
+        assert_equal(["https://pbs.twimg.com/media/B4HSEP5CUAA4xyu.png:small"], @site.preview_urls)
         assert(@site.artist_name.blank?)
         assert(@site.profile_url.blank?)
         assert(@site.artists.empty?)
@@ -171,6 +173,8 @@ module Sources
       should "work" do
         assert_equal("https://pbs.twimg.com/media/EBGp2YdUYAA19Uj.jpg:orig", @site.image_url)
         assert_equal(["https://pbs.twimg.com/media/EBGp2YdUYAA19Uj.jpg:orig"], @site.image_urls)
+        assert_equal("https://pbs.twimg.com/media/EBGp2YdUYAA19Uj.jpg:small", @site.preview_url)
+        assert_equal(["https://pbs.twimg.com/media/EBGp2YdUYAA19Uj.jpg:small"], @site.preview_urls)
         assert_equal("https://pbs.twimg.com/media/EBGp2YdUYAA19Uj.jpg:orig", @site.canonical_url)
       end