The JSON Form library is a JavaScript client-side library that takes a structured data model defined using JSON Schema as input and returns a Bootstrap-friendly HTML form that matches the schema.
The generated HTML form includes client-side validation logic that provides direct inline feedback to the user upon form submission (provided a JSON Schema validator is available). If values are valid, the JSON Form library uses submitted values to create the JavaScript data structure that matches the data model.
The layout of the generated HTML form may be entirely fine-tuned through a simple declarative mechanism.
Jsonform-rails wraps joshfire's JSONForm into an easy to bundle asset gem.
TODO: helpers as the need emerges
Add this line to your application's Gemfile:
gem 'jsonform-rails'
And then execute:
$ bundle
Or install it yourself as:
$ gem install jsonform-rails
Step 1: Make sure you're calling the javascript file in your application.js. There is no CSS, jsonform styles for bootstrap and lets you handle that:
//= require jsonform
Step 2: Use is as described in the jsonform doco
The example below creates a form that asks for the user's name and age. The user's name is a required field, while the age is optional.
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8" />
<title>Getting started with JSON Form</title>
<link rel="stylesheet" style="text/css" href="deps/opt/bootstrap.css" />
</head>
<body>
<h1>Getting started with JSON Form</h1>
<form></form>
<div id="res" class="alert"></div>
<script type="text/javascript" src="deps/jquery.min.js"></script>
<script type="text/javascript" src="deps/underscore.js"></script>
<script type="text/javascript" src="deps/opt/jsv.js"></script>
<script type="text/javascript" src="lib/jsonform.js"></script>
<script type="text/javascript">
$('form').jsonForm({
schema: {
name: {
type: 'string',
title: 'Name',
required: true
},
age: {
type: 'number',
title: 'Age'
}
},
onSubmit: function (errors, values) {
if (errors) {
$('#res').html('<p>I beg your pardon?</p>');
}
else {
$('#res').html('<p>Hello ' + values.name + '.' +
(values.age ? '<br/>You are ' + values.age + '.' : '') +
'</p>');
}
}
});
</script>
</body>
</html>Loading this page in a browser renders a form with two input fields and a submit button. The onSubmit function is called upon form submission. If you press "Submit" without entering values or if the age you enter is not a number, error messages appear next to the input fields.
NB: Paths in this example are relative to the root of the JSON Form project.
You can do much more with the JSON Form library. You may define a more complex data model that includes arrays and objects for instance, or you may control the layout of the form to include fieldsets, expandable sections or tabs. For more information, check the reference documentation for JSON Form.
If you're more of the acting type than of the reading type, the JSON Form Playground is a simple JSON Form editor that lets you try out and extend all the examples in the doc.
At a minimum, the JSON Form library depends on:
- jQuery
- The Underscore.js utility belt
The JSON Form library may require further libraries, depending on the features you need for the forms you need to render. In particular:
- ACE is needed to render rich text input fields. The deps/opt/ace folder contains a minimal set of files from ACE to render a JSON input field. Beware that the code of
ace.jsneeds to be encapsulated in(function(require,define,requirejs) {...})(undefined,undefined,undefined);before it may be used within JSON Form. - Bootstrap v2.0.3 or above is more or less needed (unless you enjoy ugly forms, that is) if you don't provide your own styles. JSON Form only needs the
bootstrap.cssfile. - The JSON Schema Validator is used to detect and report validation errors upon form submission. The deps/opt folder contains a "build" of the JSON Schema Validator for use in JSON Form.
- Bootstrap Dropdowns v2.0.3 or above is needed for
imageselectfields. - jQuery UI Sortable v1.8.20 or above is required for drag-and-drop support within arrays and tabarrays. Note the plugin itself depends on jQuery IU Core, jQuery UI Mouse, and jQuery UI Widget.
- wysihtml5 is required if the form uses
wysihtml5textarea fields. - Spectrum is required if the form uses
colorfields.
All of these libraries are in the deps folder, although you might want to check their respective Web site for more recent versions.
NB: JSON Form also uses JSON.parse and JSON.stringify which is normally already natively supported by all modern browsers. You may use a JSON library otherwise.
The JSON Form library is licensed under the MIT license.
All the libraries that JSON Form may depend on are licensed under the MIT license, except for the JSON Schema Validator, licensed under the BSD 3 Clause license and the ACE editor licensed under the Mozilla tri-license (MPL/GPL/LGPL).