odoo-survey-addons/survey_input_attachment/templates/upload_file.xml

<?xml version="1.0" encoding="utf-8"?>
<odoo>

  <template id="upload_file" name="Upload a file">
    <div class="input-file-container">
      <t t-set="user_input_line" t-value="survey.user_input_ids.filtered(lambda sui: sui.token == token).user_input_line_ids.filtered(lambda suil: suil.question_id == question)"/>
      <t t-if="user_input_line">
        <t t-if="user_input_line.file_type == 'pdf'">
          <a width="100px" height="100px" t-att-href="'data:application/pdf;base64,%s' % to_text(user_input_line.file)" target="_blank">Download <t t-esc="user_input_line.filename"/></a>
        </t>
        <t t-elif="user_input_line.file_type == 'image'">
          <img width="100px" style="height: 100px;" class="img-thumbnail" t-att-src="'data:image/*;base64,%s' % to_text(user_input_line.file)"/>
        </t>
      </t>
      <t t-else="">
        <div class="file-field">
          <input class="input-file" id="my-file" type="file" accept="image/*,application/pdf" t-att-name="prefix"/>
        </div>
        <!-- <br/> -->
      </t>
    </div>
    <script>
$(document).ready(function(){
  $(".img-thumbnail").click(function(){
    if ( $(this).height() == 240) {
      $(this).animate({
        opacity: '0.8',
        height: '100px',
        width: '100px',
      }, "slow");
    } else {
      $(this).animate({
        opacity: '0.8',
        height: '250px',
        width: '250px',
      }, "slow");
    }
  });
});
    </script>
  </template>

</odoo>