anchor.diff:      <div class="form-group">
         <label for="secret_access_key" class="col-sm-3 control-label"><%= t 'app_settings.secret_access_key' %></label>
         <div class="col-sm-7">
  -        <input type="text" class="form-control form-control-masked" id="secret_access_key" name="secret_access_key">
  +        <input type="text" class="form-control form-control-masked" id="secret_access_key" name="secret_access_key" pattern="[^\s]+" required>
           <p class="help-block"><%= t('app_settings.msg.secret_access_key') %></p>
         </div>
       </div>
  
positive.code:     <div class="form-group">
        <label for="log_directory" class="col-sm-3 control-label"><%= t 'app_settings.log_directory' %></label>
        <div class="col-sm-7">
          <input type="text" class="form-control" id="log_directory" name="log_directory">
          <p class="help-block"><%= I18n.t('app_settings.msg.log_directory') %></p>
        </div>
      </div>
  
negative.code:     <div class="form-group">
        <label for="access_key" class="col-sm-3 control-label"><%= t 'app_settings.access_key' %></label>
        <div class="col-sm-7">
          <input type="text" class="form-control" id="access_key" name="access_key" pattern="[^\s]+" required>
          <p class="help-block"><%= t('app_settings.msg.access_key') %></p>
        </div>
      </div>
  