I believe this problem is caused by the Field‘s data attribute overriding the default with something that WTForms doesn’t understand (e.g. a DB model object — it expects an int). This would happen if you have populated your form in the constructor like so: form = PostForm(obj=post) the solution is to manually set the data … Read more
You actually don’t need to go to the widget level to attach an HTML class attribute to the rendering of the field. You can simply specify it using the class_ parameter in the jinja template. e.g. {{ form.email(class_=”form-control”) }} will result in the following HTML:: <input class=”form-control” id=”email” name=”email” type=”text” value=””> to do this dynamically, … Read more
Updated for WTForms 2.1 You can now as of WTForms 2.1 (December 2015) set rendering keywords by using the render_kw= parameter to the field constructor. So the field would look like: abc = StringField(‘abc’, [InputRequired()], render_kw={“placeholder”: “test”}) Note while this is possible; it does start to bridge the line between code and presentation; so use … Read more
If you take a look at wtforms/validators.py file in line 9: import email_validator Just install the package: pip install email_validator