report federating status in nodeinfo

lib/pleroma/web/nodeinfo/nodeinfo_controller.ex

@@ -46,6 +46,7 @@ def raw_nodeinfo do
 
         data
         |> Map.merge(%{quarantined_instances: quarantined})
+        |> Map.put(:enabled, Config.get([:instance, :federating]))
       else
         %{}
       end

test/web/node_info_test.exs

@@ -84,6 +84,30 @@ test "it returns the safe_dm_mentions feature if enabled", %{conn: conn} do
     Pleroma.Config.put([:instance, :safe_dm_mentions], option)
   end
 
+  test "it shows if federation is enabled/disabled", %{conn: conn} do
+    original = Pleroma.Config.get([:instance, :federating])
+
+    Pleroma.Config.put([:instance, :federating], true)
+
+    response =
+      conn
+      |> get("/nodeinfo/2.1.json")
+      |> json_response(:ok)
+
+    assert response["metadata"]["federation"]["enabled"] == true
+
+    Pleroma.Config.put([:instance, :federating], false)
+
+    response =
+      conn
+      |> get("/nodeinfo/2.1.json")
+      |> json_response(:ok)
+
+    assert response["metadata"]["federation"]["enabled"] == false
+
+    Pleroma.Config.put([:instance, :federating], original)
+  end
+
   test "it shows MRF transparency data if enabled", %{conn: conn} do
     config = Pleroma.Config.get([:instance, :rewrite_policy])
     Pleroma.Config.put([:instance, :rewrite_policy], [Pleroma.Web.ActivityPub.MRF.SimplePolicy])