Feature: Implement FEP-2677 allowing discovery of the instance application actor

app/serializers/node_info/discovery_serializer.rb

@@ -6,6 +6,9 @@ class NodeInfo::DiscoverySerializer < ActiveModel::Serializer
   attribute :links
 
   def links
-    [{ rel: 'http://nodeinfo.diaspora.software/ns/schema/2.0', href: nodeinfo_schema_url }]
+    [
+      { rel: 'http://nodeinfo.diaspora.software/ns/schema/2.0', href: nodeinfo_schema_url },
+      { rel: 'https://www.w3.org/ns/activitystreams#Application', href: instance_actor_url },
+    ]
   end
 end

spec/requests/well_known/node_info_spec.rb

@@ -19,6 +19,10 @@ describe 'The well-known node-info endpoints' do
             include(
               rel: 'http://nodeinfo.diaspora.software/ns/schema/2.0',
               href: include('nodeinfo/2.0')
+            ),
+            include(
+              rel: 'https://www.w3.org/ns/activitystreams#Application',
+              href: end_with('/actor')
             )
           )
         )

spec/routing/well_known_routes_spec.rb

@@ -16,4 +16,16 @@ describe 'Well Known routes' do
         .to route_to('well_known/webfinger#show')
     end
   end
+
+  describe 'the nodeinfo routes' do
+    it 'routes to discovery (index) route' do
+      expect(get('/.well-known/nodeinfo'))
+        .to route_to('well_known/node_info#index', format: 'json')
+    end
+
+    it 'routes to the show route' do
+      expect(get('/nodeinfo/2.0'))
+        .to route_to('well_known/node_info#show')
+    end
+  end
 end