Merge branch 'master' into glitch-soc/merge-upstream

Conflicts:
- README.md
  discarded upstream changes
- app/controllers/api/v1/bookmarks_controller.rb
  finally merged upstream, some code style fixes
  and slightly changed pagination code
- app/controllers/application_controller.rb
  changed upstream to always return HTML error pages
  slight conflict caused by theming code
- app/models/bookmark.rb
  finally merged upstream, no real conflict
- spec/controllers/api/v1/bookmarks_controller_spec.rb
  finally merged upstream, slightly changed pagination code

spec/services/fetch_oembed_service_spec.rb

@@ -113,6 +113,24 @@ describe FetchOEmbedService, type: :service do
 
     end
 
+    context 'when endpoint is cached' do
+      before do
+        stub_request(:get, 'http://www.youtube.com/oembed?format=json&url=https://www.youtube.com/watch?v=dqwpQarrDwk').to_return(
+          status: 200,
+          headers: { 'Content-Type': 'text/html' },
+          body: request_fixture('oembed_json_empty.html')
+        )
+      end
+
+      it 'returns new provider without fetching original URL first' do
+        subject.call('https://www.youtube.com/watch?v=dqwpQarrDwk', cached_endpoint: { endpoint: 'http://www.youtube.com/oembed?format=json&url={url}', format: :json })
+        expect(a_request(:get, 'https://www.youtube.com/watch?v=dqwpQarrDwk')).to_not have_been_made
+        expect(subject.endpoint_url).to eq 'http://www.youtube.com/oembed?format=json&url=https%3A%2F%2Fwww.youtube.com%2Fwatch%3Fv%3DdqwpQarrDwk'
+        expect(subject.format).to eq :json
+        expect(a_request(:get, 'http://www.youtube.com/oembed?format=json&url=https%3A%2F%2Fwww.youtube.com%2Fwatch%3Fv%3DdqwpQarrDwk')).to have_been_made
+      end
+    end
+
     context 'when status code is not 200' do
       before do
         stub_request(:get, 'https://host.test/oembed.html').to_return(