Python wtforms 模块，TextAreaField() 实例源码

def get_node_form(node_type):
    """Get a procedurally generated WTForm, based on the dyn_schema and
    node_schema of a specific node_type.
    :type node_type: dict
    :param node_type: Describes the node type via dyn_schema, form_schema and
    parent
    """
    class ProceduralForm(Form):
        pass

    parent_prop = node_type['parent']

    ProceduralForm.name = StringField('Name', validators=[DataRequired()])
    # Parenting
    if parent_prop:
        parent_names = ", ".join(parent_prop)
        ProceduralForm.parent = HiddenField('Parent ({0})'.format(parent_names))

    ProceduralForm.description = TextAreaField('Description')
    ProceduralForm.picture = FileSelectField('Picture', file_format='image')
    ProceduralForm.node_type = HiddenField(default=node_type['name'])

    add_form_properties(ProceduralForm, node_type)

    return ProceduralForm()

def add_form_properties(form_class, node_type):
    """Add fields to a form based on the node and form schema provided.
    :type node_schema: dict
    :param node_schema: the validation schema used by Cerberus
    :type form_class: class
    :param form_class: The form class to which we append fields
    :type form_schema: dict
    :param form_schema: description of how to build the form (which fields to
            show and hide)
    """

    for prop_name, schema_prop, form_prop in iter_node_properties(node_type):

        # Recursive call if detects a dict
        field_type = schema_prop['type']

        if field_type == 'dict':
            assert prop_name == 'attachments'
            field = attachments.attachment_form_group_create(schema_prop)
        elif field_type == 'list':
            if prop_name == 'files':
                schema = schema_prop['schema']['schema']
                file_select_form = build_file_select_form(schema)
                field = FieldList(CustomFormField(file_select_form),
                                  min_entries=1)
            elif 'allowed' in schema_prop['schema']:
                choices = [(c, c) for c in schema_prop['schema']['allowed']]
                field = SelectMultipleField(choices=choices)
            else:
                field = SelectMultipleField(choices=[])
        elif 'allowed' in schema_prop:
            select = []
            for option in schema_prop['allowed']:
                select.append((str(option), str(option)))
            field = SelectField(choices=select)
        elif field_type == 'datetime':
            if form_prop.get('dateonly'):
                field = DateField(prop_name, default=date.today())
            else:
                field = DateTimeField(prop_name, default=datetime.now())
        elif field_type == 'integer':
            field = IntegerField(prop_name, default=0)
        elif field_type == 'float':
            field = FloatField(prop_name, default=0.0)
        elif field_type == 'boolean':
            field = BooleanField(prop_name)
        elif field_type == 'objectid' and 'data_relation' in schema_prop:
            if schema_prop['data_relation']['resource'] == 'files':
                field = FileSelectField(prop_name)
            else:
                field = StringField(prop_name)
        elif schema_prop.get('maxlength', 0) > 64:
            field = TextAreaField(prop_name)
        else:
            field = StringField(prop_name)

        setattr(form_class, prop_name, field)