https://www.reddit.com/r/PHPhelp/comments/625t3g/function_to_send_to_two_different_apis/

API_Input_Parameters.php

<?php

/**
 * Interface ApplicantAPI
 */
interface ApplicantAPI {
    /**
     * @param $title
     * @return int|null
     */
    public function title($title);
}

class A implements ApplicantAPI {
    /**
     * @param $title
     * @return int|null
     */
    public function title($title) {
        switch ($title) {
            case 'Mr.' :
                return 1;
            case 'Mrs.' :
                return 2;
            case 'Ms.' :
                return 3;
            case 'Miss' :
                return 4;
        }
        return null; // Return null or throw an exception.
    }
}

class B implements ApplicantAPI {
    /**
     * @param $title
     * @return int|null
     */
    public function title($title) {
        switch ($title) {
            case 'Mr.' :
                return 10;
            case 'Mrs.' :
                return 20;
            case 'Ms.' :
                return 30;
            case 'Miss' :
                return 40;
        }
        return null; // Return null or throw an exception.
    }
}

$applicantAPI = new A();
echo $applicantAPI->title('Mr.');

In the example above the value of 1 is echoed to STDOUT.