FIX: `Jobs::PullHotlinkedImages#is_valid_image_src` returns true for a generic string.

app/jobs/regular/pull_hotlinked_images.rb

@@ -28,7 +28,7 @@ module Jobs
 
       extract_images_from(post.cooked).each do |image|
         src = original_src = image['src']
-        src = "http:" + src if src.start_with?("//")
+        src = "http:#{src}" if src.start_with?("//")
 
         if is_valid_image_url(src)
           hotlinked = nil
@@ -113,17 +113,22 @@ module Jobs
       return false if Discourse.store.has_been_uploaded?(src)
       # we don't want to pull relative images
       return false if src =~ /\A\/[^\/]/i
+
       # parse the src
       begin
         uri = URI.parse(src)
       rescue URI::InvalidURIError
         return false
       end
+
+      hostname = uri.hostname
+      return false unless hostname
+
       # we don't want to pull images hosted on the CDN (if we use one)
-      return false if Discourse.asset_host.present? && URI.parse(Discourse.asset_host).hostname == uri.hostname
+      return false if Discourse.asset_host.present? && URI.parse(Discourse.asset_host).hostname == hostname
-      return false if SiteSetting.s3_cdn_url.present? && URI.parse(SiteSetting.s3_cdn_url).hostname == uri.hostname
+      return false if SiteSetting.s3_cdn_url.present? && URI.parse(SiteSetting.s3_cdn_url).hostname == hostname
       # we don't want to pull images hosted on the main domain
-      return false if URI.parse(Discourse.base_url_no_prefix).hostname == uri.hostname
+      return false if URI.parse(Discourse.base_url_no_prefix).hostname == hostname
       # check the domains blacklist
       SiteSetting.should_download_images?(src)
     end

spec/jobs/pull_hotlinked_images_spec.rb

@@ -3,6 +3,7 @@ require 'jobs/regular/pull_hotlinked_images'
 
 describe Jobs::PullHotlinkedImages do
 
+  describe '#execute' do
     let(:image_url) { "http://wiki.mozilla.org/images/2/2e/Longcat1.png" }
     let(:png) { Base64.decode64("R0lGODlhAQABALMAAAAAAIAAAACAAICAAAAAgIAAgACAgMDAwICAgP8AAAD/AP//AAAA//8A/wD//wBiZCH5BAEAAA8ALAAAAAABAAEAAAQC8EUAOw==") }
 
@@ -44,7 +45,6 @@ describe Jobs::PullHotlinkedImages do
     end
 
     describe 'onebox' do
-
       let(:media) { "File:Brisbane_May_2013201.jpg" }
       let(:url) { "https://commons.wikimedia.org/wiki/#{media}" }
       let(:api_url) { "https://en.wikipedia.org/w/api.php?action=query&titles=#{media}&prop=imageinfo&iilimit=50&iiprop=timestamp|user|url&iiurlwidth=500&format=json" }
@@ -80,7 +80,25 @@ describe Jobs::PullHotlinkedImages do
 
         expect(post.cooked).to match(/<img src=.*\/uploads/)
       end
+    end
+  end
 
+  describe '#is_valid_image_url' do
+    subject { described_class.new }
+
+    describe 'when url is invalid' do
+      it 'should return false' do
+        expect(subject.is_valid_image_url("null")).to eq(false)
+        expect(subject.is_valid_image_url("meta.discourse.org")).to eq(false)
+      end
+    end
+
+    describe 'when url is valid' do
+      it 'should return true' do
+        expect(subject.is_valid_image_url("http://meta.discourse.org")).to eq(true)
+        expect(subject.is_valid_image_url("//meta.discourse.org")).to eq(true)
+      end
+    end
   end
 
 end