pipit_category_get_path()

pipit_category_get_path() takes the returned category source (typically when you use the skip-template option) and returns the category path.

pipit_category_get_path($source);

When you have a categories field in a template (e.g. Collection item), Perch in some cases stores categories by their IDs and in other cases by their category paths. This makes it inconvenient when you skip templating and try to use the categories values. 

<perch:content id="name" type="text" label="Product Name">
<perch:content id="slug" type="slug" for="name">
<perch:categories id="categories" set="products" label="Categories" />
    $products = perch_collection('Products', [
        'skip-template' => true,
        'filter' => 'slug',
        'value' => 'my-product',
    ]);

    foreach($products as $product) {
        foreach($product['categories'] as $category) {
            // $category can be a path e.g. products/shoes/
            // or it can be an ID e.g. 34
        }
    }

A lot of the time you need the category path instead of the ID because category filtering requires paths. A common use-case is using the category paths for outputting similar items on an item’s detail page.

    $products = perch_collection('Products', [
        'skip-template' => true,
        'filter' => 'slug',
        'value' => 'my-product',
    ]);

    $categories = array();
    foreach($products as $product) {
        foreach($product['categories'] as $category) {
            $categories[] = pipit_category_get_path($category);
        }
    }

    // similar products
    perch_collection('Products', [
        'category' => $categories,
        'filter' => 'slug',
        'match' => 'neq',
        'value' => 'my-product',
    ]);

The function only attempts to retrieve the category path if $source is numerical. If $source is not numerical, the function will return the string without checking whether it is in fact a category path. This is because $source is expected to be either a category ID e.g. 34 or a category path products/shoes/.

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