xppl/app/templates/edit_book_detail.html

{% extends 'base.html' %}

{% block main %}
<div class="container">

  <a href="{{ url_for('show_book_by_id', id=book.id )}}">back</a>



  <form method="POST" action="{{ url_for('edit_book_by_id', id=book.id )}}">
    {{ form.csrf_token }}

    <div class="form-group"><h1 class="header">{{ form.title.label }} {{ form.title(size=20, class="form-control") }}</h1></div>
    <object class="no_cover" data="../../static/img/default_cover.png" type="image/png" width="150">
        <img src="../../uploads/cover/{{ book.cover }}" width="200">
      </object>
        <br>  <br>
    <div data-toggle="fieldset" id="phone-fieldset">
         {{ form.author.label }}  <button type="button" data-toggle="fieldset-add-row"
                                          data-target="#phone-fieldset">+</button>
        <table>
            <tr>
                <th></th>
                <th></th>
            </tr>
            {% for author in form.author %}
                <tr data-toggle="fieldset-entry">
                    <td>{{ author.author_name }}</td>
                    <td><button type="button" data-toggle="fieldset-remove-row" id="phone-{{loop.index0}}-remove">-</button></td>
                </tr>
            {% endfor %}
        </table>
    </div>
    <div class="form-group">
    {{ form.category.label }} {{ form.category(size=20, class="form-control") }}
  </div>
    <br>
    <button type="submit" class="btn btn-primary">Update</button>
</form>

</div>
{% endblock %}