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src/lavinmq/clustering/controller.cr

@@ -19,6 +19,10 @@ class LavinMQ::Clustering::Controller
                       "tcp://#{System.hostname}:#{@config.clustering_port}"
   end
 
+  # This method is called by the Launcher#run.
+  # The block will be yielded when the controller's prerequisites for a leader
+  # to start are met, i.e when the current node has been elected leader.
+  # The method is blocking.
   def run(&)
     spawn(follow_leader, name: "Follower monitor")
     wait_to_be_insync

src/lavinmq/launcher.cr

@@ -11,6 +11,9 @@ require "./clustering/controller"
 
 module LavinMQ
   struct StandaloneRunner
+    # The block will be yielded when the runner's prerequisites for a leader
+    # to start are met. For the standalone runner, this is immediately.
+    # The method is blocking.
     def run(&)
       yield
       loop do