code: public function buildConnectionOptions()
      {
          //Default connection
          $connection_name = $this->config->get("tail-settings.default");
  
          //Check if set for this connection
          if ($this->connection_name)
              $connection_name = $this->connection_name;
  
          $connectionOptions = $this->config->get("tail-settings.connections.$connection_name");
  
          //Adding default values to exchange_type and content_type to avoid breaking change
          if (!isset($connectionOptions['exchange_type']))
              $connectionOptions['exchange_type'] = 'direct';
          if (!isset($connectionOptions['content_type']))
              $connectionOptions['content_type'] = 'text/plain';
  
          //Set current instance properties values
          if ($this->vhost)
              $connectionOptions['vhost'] = $this->vhost;
          if ($this->exchange)
              $connectionOptions['exchange'] = $this->exchange;
          if ($this->exchange_type)
              $connectionOptions['exchange_type'] = $this->exchange_type;
          if ($this->content_type)
              $connectionOptions['content_type'] = $this->content_type;
  
          //Queue specific options
          $connectionOptions['queue_name'] = $this->queue_name;
  
          return $connectionOptions;
      }
docs: Build options set to build a connection to the queue server
  
  @return array