Add user reactivation task.

lib/mix/tasks/deactivate_user.ex

@@ -2,7 +2,7 @@ defmodule Mix.Tasks.DeactivateUser do
   use Mix.Task
   alias Pleroma.User
 
-  @shortdoc "Toggle deactivation status for a user"
+  @shortdoc "Deactivate a user"
   def run([nickname]) do
     Mix.Task.run("app.start")
 

lib/mix/tasks/reactivate_user.ex

@@ -0,0 +1,13 @@
+defmodule Mix.Tasks.ReactivateUser do
+  use Mix.Task
+  alias Pleroma.User
+
+  @shortdoc "Reactivate a user"
+  def run([nickname]) do
+    Mix.Task.run("app.start")
+
+    with user <- User.get_by_nickname(nickname) do
+      User.deactivate(user, false)
+    end
+  end
+end

lib/pleroma/user.ex

@@ -622,8 +622,8 @@ defmodule Pleroma.User do
     )
   end
 
-  def deactivate(%User{} = user) do
-    new_info = Map.put(user.info, "deactivated", true)
+  def deactivate(%User{} = user, status \\ true) do
+    new_info = Map.put(user.info, "deactivated", status)
     cs = User.info_changeset(user, %{info: new_info})
     update_and_set_cache(cs)
   end

lib/pleroma/web/activity_pub/activity_pub.ex

@@ -44,7 +44,7 @@ defmodule Pleroma.Web.ActivityPub.ActivityPub do
   defp check_actor_is_active(actor) do
     if not is_nil(actor) do
       with user <- User.get_cached_by_ap_id(actor),
-           nil <- user.info["deactivated"] do
+           false <- !!user.info["deactivated"] do
         :ok
       else
         _e -> :reject