sample form with flask-mongoengine wtform validation

sample_form.html

<form method="POST" role="form">
	{{ form.csrf_token }}

	<legend><h3>Share Your Ideas</h3></legend>

	{% if form.errors %}
	    <ul class="errors">
	        {% for field_name, field_errors in form.errors|dictsort if field_errors %}
	            {% for error in field_errors %}
	                <li>{{ form[field_name].label }}: {{ error }}</li>
	            {% endfor %}
	        {% endfor %}
	    </ul>
	{% endif %}

	<div class="form-group">
		{{ form.creator.label() }}
		{{ form.creator(class='form-control', type='textinput') }}
		<!--
		<label for="creator">First Name</label>
		<input type="text" id="creator" name="creator" class="form-control" value=""> 
		-->
	</div>

	<div class="form-group">
		{{ form.title.label() }}
		{{ form.title(class='form-control', type='textinput') }}
		<!-- 
		<label for="title">Project Title</label>
		<input type="text" id="title" name="title" class="form-control">
		-->
	</div>
	
	<div class="form-group">
		{{ form.idea.label() }}
		{{ form.idea(class='form-control', type='textarea') }}
		<!-- <label for="idea">Idea description</label>
		<textarea name="idea" id="idea" class="form-control"></textarea>
		-->
	</div>

	<label>Category</label>
	<p class="help-block">Select as many as you need.</p>
	{# comment - loop through categories and create checkboxes #}
	{% for c in categories|sort %}
	<div class="checkbox">
		<label>
			<input type="checkbox" \
				name="categories" 
				value="{{ c|replace(" ","_") }}" {% if c|replace(" ","_") in form.categories.data %}checked=checked{% endif %}> 
			{{ c|title }}
		</label>
	</div>
	{% endfor %}



	<button type="submit" class="btn btn-primary">Add Idea</button>
</form>