elementsToDot.php

<?php

use Illuminate\Support\Collection;

/**
 * This macro will help you turn any nested array into an associative array,
 * where each element is represented with dot notation.
 *
 * For example:
 *
 * $arr = [
 *    'a' => 1,
 *    'b' => [
 *        'c' => 2,
 *        'd' => [
 *            'e' => 3,
 *        ],
 *     ],
 * ];
 *
 * will get coverted to:
 *
 * $arr = [
 *     'a' => 1,
 *     'b.c' => 2,
 *     'b.d.e' => 3,
 * ];
 */
Collection::macro('elementsToDot', function () {
    /**
     * @var \Illuminate\Support\Collection $this
     */
    $recursiveIterator = new RecursiveIteratorIterator(new RecursiveArrayIterator($this->toArray()));
    $result = [];

    foreach ($recursiveIterator as $leafValue) {
        $keys = [];

        foreach (range(0, $recursiveIterator->getDepth()) as $depth) {
            $keys[] = $recursiveIterator->getSubIterator($depth)->key();
        }

        $result[implode('.', $keys)] = $leafValue;
    }

    return $result;
});