README

Configuration

Create a YAML file:

You can copy the Resources/sample/config.yaml in your app (in /frontend/polyfill/config.yaml for example).

You can configure this path by overriding this parameters in your app:

parameters:
    cws.polyfill.config_path: /frontend/polyfill/config.yaml

Activate the polyfills you need by setting active: true in this config file.

Services

Add this line in the import section of your services.yaml

imports:
    - { resource: '@CwsFrontPolyfillBundle/Resources/config/services.xml' }

Javascript support tests

Get the active polyfill list:

With an object list

{% set polyfillList = get_front_polyfill_list() %}

<script>
var myPolyfillArray = [
{%- for name, polyfill in polyfillList.list -%}
    {
        "test": {{ polyfill.test|raw }},
        "name": "{{ name|raw }}"
    }{{ loop.last ? '' : ',' }}
{%- endfor -%}
];
</script>

With a JS array-like string

var myPolyfillArray = {{ get_front_polyfill_list('js') }};

This will give :

var myPolyfillArray = [
    {
        "test": test1,
        "name": "test1"
    },{
        "test": test2,
        "name": "test2"
    },
    ...
];

You can change the name of the properties:

var myPolyfillArray = {{ get_front_polyfill_list('js', 'a', 'b') }};

Results in :

var myPolyfillArray = [{
        "b": test1,
        "a": "test1"
    },{
        "b": test2,
        "a": "test2"
    },
    ...
];

Here a full example to create an url like 'js/pf1-pf2-pf3.js':

{% set polyfillArrayString = get_front_polyfill_list('js') %}

<script>
    let polyfillContentUrl;

    {%- if polyfillArrayString is defined and polyfillArrayString|length > 2 -%}
        let neededPolyfill = [];

        {{ polyfillArrayString }}
            .forEach( function( polyfill ) {
                if (typeof polyfill.test === 'function' && polyfill.test() ||
                    typeof polyfill.test !== 'function' && polyfill.test) {
                    neededPolyfill.push( polyfill.name );
                }
            });

        if ( neededPolyfill.length ) {
            polyfillContentUrl = `js/${ neededPolyfill.join( '-' ) }.js`;
        }
    {%- endif -%}

    [
        polyfillContentUrl,
        '1.js',
        '2.js'
    ].forEach( function( src ) {
        if ( !src ) {
            return;
        }
        var script = document.createElement('script');
        script.src = src;
        script.async = false;
        document.head.appendChild(script);
    } );
</script>

Polyfill loading

Use the array of test to create an url to load the polyfill content.

There is 2 ways to load the polyfills:

1/ The polyfill names are contained in the filename itself and separated by -

This is the recommended way to do it because this way allow you to create a real file. Handy with Symfony as if the file exists, it will not be rerendered.

<script src="js/polyfill-domch-eachnl-picture.js"></script>

Inside the Twig file that render the response for polyfill-domch-eachnl-picture.js (and save the file if you want):

{{ get_front_polyfill_content()|raw }}

// Other stuff in JS

The route to this file MUST contains a placeholder. By default its name is polyfill_list. So, in our example /js/polyfill-domch-eachnl-picture.js, the route must be /js/polyfill-{polyfill_list}.js

You can configure the placeholder name in the parameters.yaml:

parameters:
    cws.polyfill.route_placeholder: polyfill_list

When there is a clear cache action, it is recommended to delete those generated files as well.

2/ The polyfill names are contained in the query string and separated by &

<script src="js/polyfill.js?domch&eachnl&picture"></script>

Tou have to specify it using the parameter query of the get_front_polyfill_content TWIG function.

Inside the Twig file that render the response for polyfill.js:

{{ get_front_polyfill_content('query')|raw }}

// Other stuff in JS