def environment_variables
      vars = @process.environment_variables.merge({
        'PROC_NAME' => self.description,
        'PID_FILE' => self.pid_file_path,
        'APP_ROOT' => @process.config.root
      })
      vars['PORT'] = @port.to_s if @port
      vars
    end
def environment_variables
      vars = @process.environment_variables.merge({
        'PROC_NAME' => self.description,
        'PID_FILE' => self.pid_file_path,
        'APP_ROOT' => @process.config.root
      })
      vars['PORT'] = @port.to_s if @port
      vars
    end
Return an array of environment variables that should be set