Synopsis

Transparency is a client-side template engine which binds data to DOM. Just call .render(data).

<div id="template">
  <span class="greeting"></span>
  <span data-bind="name"></span>
</div>

var hello = {
  greeting: 'Hello',
  name:     'world!'
};

$('#template').render(hello);

<div id="template">
  <span class="greeting">Hello</span>
  <span data-bind="name">world!</span>
</div>

Features

• Semantic data binding - No need for <%=foo%> or {{foo}} assignments
• Collection rendering - No need for hand-written loops
• Valid HTML templates - Write templates as a part of the HTML, in plain HTML
• View logic in JavaScript - No crippled micro-template language, just plain JavaScript functions

Transparency is compatible with IE9+, Chrome, Firefox, iOS, Android and other mobile browsers. Support for IE8 requires jQuery.

Community

• IRC: freenode/#transparency.js
• Google Groups: [email protected]

We are looking for new maintainers. Anyone with an accepted pull request will get commit rights. Current maintainers are

• pyykkis
• rikukissa

Fiddle

Try Transparency with interactive examples.

Install

curl https://raw.github.com/leonidas/transparency/master/dist/transparency.min.js

# Or with Bower
npm install -g bower
bower install transparency

Require with script tags

<script src="js/jquery-1.7.1.min.js"></script>
<script src="js/transparency.min.js"></script>

or with AMD

require(['jquery', 'transparency'], function($, Transparency) {

  // Without jQuery
  Transparency.render(document.getElementById('template'), data);

  // With jQuery
  jQuery.fn.render = Transparency.jQueryPlugin;
  $('#template').render(data);
});

Node.js

npm install transparency

For server-side use, see examples/hello-server.

API documentation

Here are short and detailed examples how to use Transparency. For more elaborate examples, see User manual and FAQ. Feel free to add your own examples in the wiki, too!

Implementation details are explained in the annotated source code.

Binding values

Transparency binds values in-place. That means, you don't need to write separate template sections on your page. Instead, compose just a normal, static html page and start binding some dynamic values on it!

By default, Transparency binds JavaScript objects to a DOM element by id, class,name attribute and data-bind attribute. Default behavior can be changed by providing a custom matcher function, as explained in section Configuration. Values are escaped before rendering.

Template:

<div id="container">
  <div id="hello"></div>
  <div class="goodbye"></div>
  <input type="text" name="greeting" />
  <button class="hi-button" data-bind="hi-label"></button>
</div>

Javascript:

var hello = {
  hello:      'Hello',
  goodbye:    '<i>Goodbye!</i>',
  greeting:   'Howdy!',
  'hi-label': 'Terve!' // Finnish i18n
};

// with jQuery
$('#container').render(hello);

// ..or without
Transparency.render(document.getElementById('container'), hello);

Result:

<div class="container">
  <div id="hello">Hello</div>
  <div class="goodbye">lt;i&gt;Goodbye!&lt;/i&gt;</div>
  <input type="text" name="greeting" value="Howdy!" />
  <button class="hi-button" data-bind="hi-label">Terve!</button>
</div>

Rendering a list of models

Template:

<ul id="activities">
  <li class="activity"></li>
</ul>

Javascript:

var activities = [
  {activity: 'Jogging'},
  {activity: 'Gym'},
  {activity: 'Sky Diving'},
];

$('#activities').render(activities);

// or
Transparency.render(document.getElementById('activities'), activities);

Result:

<ul id="activities">
  <li class="activity">Jogging</li>
  <li class="activity">Gym</li>
  <li class="activity">Sky Diving</li>
</ul>

Rendering a list of plain values

With plain values, Transparency can't guess how you would like to bind the data to DOM, so a bit of help is needed. Directives are just for that.

Access to the plain values within the directives is provided through this.value. There's a whole lot more to say about the directives, but that's all we need for now. For the details, see section Directives.

Template:

<div>
  <div class="comments">
    <label>Comments:</label><span class="comment"></span>
  </div>
</div>

Javascript:

var comments, directives;

comments = ["That rules", "Great post!"];

// See section 'Directives' for the details
directives = {
  comment: {
    text: function() {
      return this.value;
    }
  }
};

$('.comments').render(comments, directives);

Result:

<div>
  <div class="comments">
    <label>Comments</label><span class="comment">That rules</span>
    <label>Comments</label><span class="comment">Great post!</span>
  </div>
</div>

Nested lists

Template:

<div class="container">
  <h1 class="title"></h1>
  <p class="post"></p>
  <div class="comments">
    <div class="comment">
      <span class="name"></span>
      <span class="text"></span>
    </div>
  </div>
</div>

Javascript:

var post = {
  title:    'Hello World',
  post:     'Hi there it is me',
  comments: [ {
      name: 'John',
      text: 'That rules'
    }, {
      name: 'Arnold',
      text: 'Great post!'
    }
  ]
};

$('.container').render(post);

Result:

<div class="container">
  <h1 class="title">Hello World</h1>
  <p class="post">Hi there it is me</p>
  <div class="comments">
    <div class="comment">
      <span class="name">John</span>
      <span class="text">That rules</span>
    </div>
    <div class="comment">
      <span class="name">Arnold</span>
      <span class="text">Great post!</span>
    </div>
  </div>
</div>

Nested objects

Template:

<div class="person">
  <div class="firstname"></div>
  <div class="lastname"></div>
  <div class="address">
    <div class="street"></div>
    <div class="zip"><span class="city"></span></div>
  </div>
</div>

Javascript:

var person = {
  firstname: 'John',
  lastname:  'Wayne',
  address: {
    street: '4th Street',
    city:   'San Francisco',
    zip:    '94199'
  }
};

$('.person').render(person);

Result:

<div class="container">
  <div class="firstname">John</div>
  <div class="lastname">Wayne</div>
  <div class="address">
    <div class="street">4th Street</div>
    <div class="zip">94199<span class="city">San Francisco</span></div>
  </div>
</div>

Directives

Directives are actions Transparency performs while rendering the templates. They can be used for setting element text or html content and attribute values, e.g., class, src or href.

Directives are plain javascript functions defined in a two-dimensional object literal, i.e.,

directives[element][attribute] = function(params) {...}

where element is value of id, class, name attribute or data-bind attribute of the target element. Similarly, attribute is the name of the target attribute.

When a directive function is executed, this is bound to the current model object. In addition, the directive function receives current element as params.element, current index as params.index and current value as params.value.

The return value of a directive function is assigned to the matching element attribute. The return value should be string, number or date.

Template:

<div class="person">
  <span class="name">My name is </span>
  <a class="email"></a>
</div>

Javascript:

var person, directives;

person = {
  firstname: 'Jasmine',
  lastname:  'Taylor',
  email:     '[email protected]'
};

directives = {
  name: {
    text: function(params) {
      return params.value + this.firstname + " " + this.lastname;
    }
  },

  email: {
    href: function(params) {
      return "mailto:" + this.email;
    }
  }
};

$('.person').render(person, directives);

Result:

<div class="person">
  <span class="name">My name is Jasmine Taylor</span>
  <a class="email" href="mailto:[email protected]">[email protected]</a>
</div>

Nested directives

Template:

<div class="person">
  <span class="name"></span>
  <span class="email"></span>
  <div class="friends">
    <div class="friend">
      <span class="name"></span>
      <span class="email"></span>
    </div>
  </div>
</div>

Javascript:

person = {
  firstname:  'Jasmine',
  lastname:   'Taylor',
  email:      '[email protected]',
  friends:    [ {
      firstname: 'John',
      lastname:  'Mayer',
      email:     '[email protected]'
    }, {
      firstname: 'Damien',
      lastname:  'Rice',
      email:     '[email protected]'
    }
  ]
};

nameDecorator = function() { "<b>" + this.firstname + " " + this.lastname + "</b>"; };

directives = {
  name: { html: nameDecorator },

  friends: {
    name: { html: nameDecorator }
  }
};

$('.person').render(person, directives);

Result:

<div class="person">
  <span class="name"><b>Jasmine Taylor</b></span>
  <span class="email">[email protected]</span>
  <div class="friends">
    <div class="friend">
      <span class="name"><b>John Mayer</b></span>
      <span class="email">[email protected]</span>
    </div>
    <div class="friend">
      <span class="name"><b>Damien Rice</b></span>
      <span class="email">[email protected]</span>
    </div>
  </div>
</div>

Configuration

Transparency can be configured to use custom matcher for binding the values to DOM elements.

For example, one might want to bind only with data-bind attribute, but not with class or id attributes. Custom matcher function should take key and element as parameters and return true if the corresponding value should be bind to the given DOM element.

// The custom matcher gets Transparency `Element` wrapper with following properties
// element.el:         Raw DOM element
// element.name:       Lower-cased name of the DOM element, e.g., 'input'
// element.classNames: List of class names of the DOM element, e.g., ['person', 'selected']
Transparency.matcher = function(element, key) {
  return element.el.getAttribute('data-bind') == key;
};

// Values are bind only with 'data-bind' attribute
template.render({name: "Will Smith"});

Debugging templates, data and Transparency

http://leonidas.github.com/transparency/ is great place to fiddle around with your data and templates.

To enable debug mode, call .render with a {debug: true} config and open the javascript console.

$('container').render(data, {}, {debug: true});

Development environment

Install node.js 0.8.x and npm. Then, in the project folder

$ npm install grunt -g  # command-line build tool to enable TDD, auto-complation and minification
$ npm install           # Install the development dependencies
$ grunt                 # Compile, run tests, minify and start watching for modifications

The annotated source code should give a decent introduction.

Contributing

All the following are appreciated, in an asceding order of preference

1. A feature request or a bug report
2. Pull request with a failing unit test
3. Pull request with unit tests and corresponding implementation

In case the contribution is changing Transparency API, please create a ticket first in order to discuss and agree on design.