How to add Schema.org markup to Yii2 pages

https://schema.org is a markup system that allows to embed structured data on their web pages for use by search engines and other applications. Let's see how to add Schema.org to our pages on Yii2 based websites using JSON-LD.

Basically what we need is to embed something like this in our pages:

<script type="application/ld+json">
{ 
  "@context": "http://schema.org/",
  "@type": "Movie",
  "name": "Avatar",
  "director": 
    { 
       "@type": "Person",
       "name": "James Cameron",
       "birthDate": "1954-08-16"
    },
  "genre": "Science fiction",
  "trailer": "../movies/avatar-theatrical-trailer.html" 
}
</script>

But we don't like to write scripts like this on Yii2, so let's try to do it in other, more PHP, way.

In the layout we can define some general markup for our website, so we add the following snippet at the beginning of the@app/views/layouts/main.php file:

<?= \yii\helpers\Html::script(isset($this->params['schema'])
    ? $this->params['schema']
    : \yii\helpers\Json::encode([
        '@context' => 'https://schema.org',
        '@type' => 'WebSite',
        'name' => Yii::$app->name,
        'image' => $this->image,
        'url' => Yi::$app->homeUrl,
        'descriptions' => $this->description,
        'author' => [
            '@type' => 'Organization',
            'name' => Yii::$app->name,
            'url' => 'https://www.hogarencuba.com',
            'telephone' => '+5352381595',
        ]
    ]), [
    'type' => 'application/ld+json',
]) ?>

Here we are using the Html::script($content, $options) to include the script with the necessary type option, and Json::encode($value, $options) to generate the JSON. Also we use a page parameter named schema to allow overrides on the markup from other pages. For example, in @app/views/real-estate/view.php we are using:

$this->params['schema'] = \yii\helpers\Json::encode([
    '@context' => 'https://schema.org',
    '@type' => 'Product',
    'name' => $model->title,
    'description' => $model->description,
    'image' => array_map(function ($item) {
        return $item->url;
    }, $model->images),
    'category' => $model->type->description_es,
    'productID' => $model->code,
    'identifier' => $model->code,
    'sku' => $model->code,
    'url' => \yii\helpers\Url::current(),
    'brand' => [
        '@type' => 'Organization',
        'name' => Yii::$app->name,
        'url' => 'https://www.hogarencuba.com',
        'telephone' => '+5352381595',
    ],
    'offers' => [
        '@type' => 'Offer',
        'availability' => 'InStock',
        'url' => \yii\helpers\Url::current(),
        'priceCurrency' => 'CUC',
        'price' => $model->price,
        'priceValidUntil' => date('Y-m-d', strtotime(date("Y-m-d", time()) . " + 365 day")),
        'itemCondition' => 'https://schema.org/UsedCondition',
        'sku' => $model->code,
        'identifier' => $model->code,
        'image' => $model->images[0],
        'category' => $model->type->description_es,
        'offeredBy' => [
            '@type' => 'Organization',
            'name' => Yii::$app->name,
            'url' => 'https://www.hogarencuba.com',
            'telephone' => '+5352381595',
        ]
    ]
]);

Here we redefine the schema for this page with more complex markup: a product with an offer.

This way all the pages on our website will have a schema.org markup defined: in the layout we have a default and in other pages we can redefine setting the value on $this->params['schema'].