JSFiddle - React, Tailwind, and code Playground

HTML

<script src="https://cdnjs.cloudflare.com/ajax/libs/parsley.js/2.6.0/parsley.min.js"></script>
<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/twitter-bootstrap/4.0.0-alpha.5/css/bootstrap.css">
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.1.1/jquery.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/parsley.js/2.6.0/parsley.js"></script>
<div id="parsley-div">
  <div class="form-group">
    <label for="city">City</label>
    <input type="text" class="form-control"  data-parsley-required data-parsley-required-message="Please enter a city name.">
  </div>
  <button class="btn btn-primary">Save Changes</button>
</div>

<form id="parsley-form" style="margin-top: 40px;">
  <div class="form-group">
    <label for="city">City</label>
    <input type="text" class="form-control"  data-parsley-required data-parsley-required-message="Please enter a city name.">
  </div>
  <button class="btn btn-primary">Save Changes</button>
</form>

JavaScript

$('#parsley-div').find('button').click(function(){
  $('#parsley-div :input:not(:button)').parsley().validate();
});

$('#parsley-form').find('button').click(function(){
  $('#parsley-form').parsley().validate();
});