moebooru: delegate to substrategy based on post source (#3911).

If the yande.re or konachan.com post has a source from a supported site,
for example Pixiv or Twitter, then delegate the artist and commentary
lookup to that substrategy.

Only do this for sources from recognized sites, not the null strategy.

app/logical/sources/strategies.rb

@@ -12,15 +12,12 @@ module Sources
         Strategies::Nijie, 
         Strategies::Pawoo,
         Strategies::Moebooru,
-
-        Strategies::Null # MUST BE LAST!
       ]
     end
 
-    def self.find(url, referer=nil)
-      all
-        .detect { |strategy| strategy.match?(url, referer) }
-        .new(url, referer)
+    def self.find(url, referer=nil, default: Strategies::Null)
+      strategy = all.detect { |strategy| strategy.match?(url, referer) } || default
+      strategy&.new(url, referer)
     end
 
     def self.canonical(url, referer)

app/logical/sources/strategies/moebooru.rb

@@ -36,6 +36,8 @@ module Sources
       URL_SLUG = %r!/(?:yande\.re%20|Konachan\.com%20-%20)(?<id>\d+).*!i
       IMAGE_URL = %r!#{BASE_URL}/(?<type>image|jpeg|sample)/(?<md5>\h{32})#{URL_SLUG}?\.(?<ext>jpg|jpeg|png|gif)\z!i
 
+      delegate :artist_name, :profile_url, :unique_id, :artist_commentary_title, :artist_commentary_desc, :dtext_artist_commentary_title, :dtext_artist_commentary_desc, to: :sub_strategy, allow_nil: true
+
       def self.match?(*urls)
         urls.compact.any? { |x| x.match?(BASE_URL) }
       end
@@ -73,14 +75,6 @@ module Sources
         image_url
       end
 
-      def profile_url
-        nil
-      end
-
-      def artist_name
-        nil
-      end
-
       def tags
         api_response[:tags].to_s.split.map do |tag|
           [tag.tr("_", " "), "https://#{site_name}/post?tags=#{CGI.escape(tag)}"]
@@ -109,6 +103,10 @@ module Sources
       memoize :api_response
 
       concerning :HelperMethods do
+        def sub_strategy
+          @sub_strategy ||= Sources::Strategies.find(api_response[:source], default: nil)
+        end
+
         def file_host
           case site_name
           when "yande.re" then "files.yande.re"

app/logical/sources/strategies/null.rb

@@ -1,10 +1,6 @@
 module Sources
   module Strategies
     class Null < Base
-      def self.match?(*urls)
-        true
-      end
-
       def image_urls
         [url]
       end

test/unit/sources/moebooru_test.rb

@@ -2,7 +2,7 @@ require "test_helper"
 
 module Sources
   class MoebooruTest < ActiveSupport::TestCase
-    def assert_source_data_equals(url, referer = nil, site_name: nil, image_url: nil, page_url: nil, preview_url: nil, size: nil, tags: [])
+    def assert_source_data_equals(url, referer = nil, site_name: nil, image_url: nil, page_url: nil, preview_url: nil, size: nil, tags: [], profile_url: nil)
       site = Sources::Strategies.find(url)
 
       assert_equal(site_name, site.site_name)
@@ -13,6 +13,7 @@ module Sources
       assert_equal([preview_url], site.preview_urls)
       assert_equal(page_url, site.page_url) if page_url.present?
       assert_equal(tags.sort, site.tags.map(&:first).sort)
+      assert_equal(profile_url.to_s, site.profile_url.to_s)
       assert_equal(size, site.size)
       assert_nothing_raised { site.to_h }
     end
@@ -35,7 +36,8 @@ module Sources
           @page = "https://yande.re/post/show/482880"
           @tags = ["bayashiko", "journey to the west", "sun wukong"]
           @size = 362_554
-          @data = { site_name: "yande.re", preview_url: @prev, image_url: @full, page_url: @page, size: @size, tags: @tags}
+          @profile_url = "https://twitter.com/apononori"
+          @data = { site_name: "yande.re", preview_url: @prev, image_url: @full, page_url: @page, size: @size, tags: @tags, profile_url: @profile_url }
 
           assert_source_data_equals(@samp, @data)
           assert_source_data_equals(@full, @data)
@@ -52,7 +54,7 @@ module Sources
           @page = "https://yande.re/post/show/398018"
           @tags = ["misaki kurehito", "saenai heroine no sodatekata", "sawamura spencer eriri", "detexted", "thighhighs"]
           @size = 9_118_998
-          @data = { site_name: "yande.re", preview_url: @prev, image_url: @full, page_url: @page, size: @size, tags: @tags}
+          @data = { site_name: "yande.re", preview_url: @prev, image_url: @full, page_url: @page, size: @size, tags: @tags, profile_url: nil }
 
           assert_source_data_equals(@samp, @data)
           assert_source_data_equals(@jpeg, @data)
@@ -69,7 +71,7 @@ module Sources
           @full = "https://files.yande.re/image/fb27a7ea6c48b2ef76fe915e378b9098.png"
           @tags = []
           @size = 9_118_998
-          @data = { site_name: "yande.re", preview_url: @prev, image_url: @full, page_url: @page, size: @size, tags: @tags}
+          @data = { site_name: "yande.re", preview_url: @prev, image_url: @full, page_url: @page, size: @size, tags: @tags, profile_url: nil }
 
           assert_source_data_equals(@samp, @data)
           assert_source_data_equals(@jpeg, @data)
@@ -92,8 +94,9 @@ module Sources
             girls_frontline hara_shoutarou hoodie long_hair pantyhose scar skirt
             twintails ump-45_(girls_frontline) ump-9_(girls_frontline)
           ].map { |tag| tag.tr("_", " ") }
+          @profile_url = "https://www.pixiv.net/member.php?id=22528152"
 
-          @data = { site_name: "konachan.com", preview_url: @prev, image_url: @full, page_url: @page, size: @size, tags: @tags}
+          @data = { site_name: "konachan.com", preview_url: @prev, image_url: @full, page_url: @page, size: @size, tags: @tags, profile_url: @profile_url }
           assert_source_data_equals(@samp, @data)
           assert_source_data_equals(@jpeg, @data)
           assert_source_data_equals(@full, @data)