RecursiveSnakeCaseToCamelCaseKeys

<?php


namespace CSID\IMC\Baseline\CoreBundle\Model\Traits;


trait RecursiveSnakeCaseToCamelCaseKeys
{
    /**
     * Recursively iterate through an array with snake_case keys
     * and convert those keys to camelCase.
     * @param array $snakeCaseArray
     * @return array
     */
    public function recursiveSnakeCaseToCamelCaseKeys(array $snakeCaseArray): array
    {
        $result = [];
        foreach ($snakeCaseArray as $key => $val) {
            $newKey = $this->toCamelCase($key);

            if (!is_array($val)) {
                $result[$newKey] = $val;
            } else {
                $result[$newKey] = $this->recursiveSnakeCaseToCamelCaseKeys($val);
            }
        }

        return $result;
    }

    /**
     * Convert snake_case words to camelCase
     * @param string $value
     * @return string
     */
    public function toCamelCase(string $value): string
    {
        $valueArray = explode('_', $value);
        return $this->iterateSnakeCaseWordArray($valueArray);
    }

    /**
     * Iterate through a word array
     * Capitalize the first letter of every word
     * Join each word.
     * @param array $wordArray
     * @return string
     */
    public function iterateSnakeCaseWordArray(array $wordArray): string
    {
        $i = 0;
        $capitalizedWords = [];
        foreach ($wordArray as $word) {
            $i === 0
                ? $capitalizedWords[] = $word
                : $capitalizedWords[] = ucwords($word);

            $i++;
        }

        return implode('', $capitalizedWords);
    }
}

This trait recursively converts snake_case keys to camelCase for multi-nested associative arrays.