refactor: App on startup to conditionally start mqtt publisher

Author: naqvis

src/app.cr

@@ -58,9 +58,21 @@ module PlaceOS::Source
     end
   end
 
+  # Configure the database connection. First check if PG_DATABASE_URL environment variable
+  # is set. If not, assume database configuration are set via individual environment variables
+  if pg_url = ENV["PG_DATABASE_URL"]?
+    PgORM::Database.parse(pg_url)
+  else
+    PgORM::Database.configure { |_| }
+  end
+
   publisher_managers = [] of PublisherManager
 
-  publisher_managers << MqttBrokerManager.new
+  if PlaceOS::Model::Broker.count > 0
+    publisher_managers << MqttBrokerManager.new
+  else
+    puts "skipping Mqtt Broker\n"
+  end
 
   influx_host, influx_api_key = INFLUX_HOST, INFLUX_API_KEY
 
@@ -71,14 +83,6 @@ module PlaceOS::Source
     publisher_managers << InfluxManager.new(influx_host, influx_api_key)
   end
 
-  # Configure the database connection. First check if PG_DATABASE_URL environment variable
-  # is set. If not, assume database configuration are set via individual environment variables
-  if pg_url = ENV["PG_DATABASE_URL"]?
-    PgORM::Database.parse(pg_url)
-  else
-    PgORM::Database.configure { |_| }
-  end
-
   # Start application manager
   manager = Manager.new(publisher_managers)
   manager.start