DatabindExtension

One-way databinding extension for Nunjucks templating engine

Options

When constructing the DatabindExtension, you can supply the following options:

• updateMode, Determines how the bindings are updated. Can be 'auto', 'proxy', 'pull' or 'manual'. Default is 'auto' which will detect the best approach based on browser features.

Usage

To use the extension you must create a Nunjucks environment and add the DatabindExtension extension

var nunjucksEnv = new nunjucks.Environment(new nunjucks.WebLoader('/templates'), {
    autoescape: true
});
nunjucksEnv.addExtension('BindExtension', new DatabindExtension({}));

Then, you create the context for nunjucks a little differently:

var context = databindExtension.createContext({
    displayName: 'person',
    items: ['Test1', 'Test2']
});

The DatabindExtension extensions provides a bind tag for you to use in your templates. This will add a data-nunjucks-databind tag to any first-level children elements

{% bind %}
    <ul>
    {% for item in items %}
        <li>{{item}}</li>
    {% endfor %}
    </ul>
{% endbind %}

Any content within the {% bind %}{% endBind %} tags will be automatically re-rendered when the template's data object changes. However, doing a full render whenever any part of the object is modified is far from optimal and can have unintended side effects, so the {% bind %} tag accepts an optional parameter indicating what part of the object needs to change to trigger a re-render.

{% bind "items" %}
    <ul>
    {% for item in items %}
        <li>{{item}}</li>
    {% endfor %}
    </ul>
{% endbind %}

Including "items" tells the extension to only update this part of the template when the corresponding items attribute is modified.

Instance Methods

createContext(context) Create a context object based on an input object which is monitored for changes

updateBindings([force]) Update bindings if they have changed. Set force to true to force the update regardless of change