datetimepicker-example

app.py

from flask import Flask, render_template
from flask_bootstrap import Bootstrap
from flask_wtf import Form
from wtforms.fields import DateField


app = Flask(__name__)
app.config['SECRET_KEY'] = 'secret'
Bootstrap(app)

class MyForm(Form):
    date = DateField(id='datepick')

@app.route('/')
def index():
    form = MyForm()
    return render_template('index.html', form=form)

index.html

{% extends "bootstrap/base.html" %}
{% import "bootstrap/wtf.html" as wtf %}

{% block title %}This is an example page{% endblock %}

{% block head %}
  {{ super() }}
  <link type="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/bootstrap-datetimepicker/4.17.47/css/bootstrap-datetimepicker.min.css">
{% endblock %}

{% block content %}
  <div class="container">
    <h1>Hello, Bootstrap</h1>
    <div class="row">
      <div class='col-sm-6'>
        {{ wtf.quick_form(form) }}
      </div>
    </div>
  </div>
{% endblock %}

{% block scripts %}
  {{ super() }}
  <script type="text/javascript" src="https://cdnjs.cloudflare.com/ajax/libs/moment.js/2.18.1/moment.min.js"></script>
  <script type="text/javascript" src="https://cdnjs.cloudflare.com/ajax/libs/bootstrap-datetimepicker/4.17.47/js/bootstrap-datetimepicker.min.js"></script>
  <script type="text/javascript">
    $(function () {
      $('#datepick').datetimepicker();
    });
  </script>
{% endblock %}

Well, simply use DateTimeLocalField would solve all these sufferings.

Sample Here

from flask_wtf import FlaskForm
from wtforms.fields import StringField, TextAreaField, SubmitField, DateTimeLocalField
from wtforms.validators import DataRequired, Optional


class PasteForm(FlaskForm):
    title = StringField('Title here')
    body = TextAreaField('Just paste', validators=[DataRequired()])
    expiry = DateTimeLocalField('Expiry date', validators=[Optional()])
    submit = SubmitField('Submit')

And the HTML is quite simple, No JS needed except basic BootStrap