message bus fixes and diagnostics

lib/message_bus_diags.rb

@@ -0,0 +1,32 @@
+class MessageBusDiags
+
+  @host_info = {}
+
+  def self.my_id
+    @my_id ||= "#{`hostname`}-#{Process.pid}"
+  end
+
+  def self.seen_host(name)
+    @host_info[name] = DateTime.now
+  end
+
+  def self.establish_peer_names
+    MessageBus.publish "/server-name", {channel: "/server-name-reply/#{my_id}"}
+  end
+
+  def self.seen_hosts
+    @host_info
+  end
+  
+  unless @subscribed
+
+    MessageBus.subscribe "/server-name-reply/#{my_id}" do |msg|
+      MessageBusDiags.seen_host(msg.data)
+    end
+
+    MessageBus.subscribe "/server-name" do |msg|
+      MessageBus.publish msg.data["channel"], MessageBusDiags.my_id
+    end
+    @subscribed = true
+  end
+end