uninstall.php

<?php
/**
 * Uninstall routine. Runs when the Plugin is deleted
 * at Plugins > Delete.
 *
 * @package CKWC
 * @author ConvertKit
 */

// If uninstall.php is not called by WordPress, die.
if ( ! defined( 'WP_UNINSTALL_PLUGIN' ) ) {
	die;
}

// Only WordPress and PHP methods can be used. Plugin classes and methods
// are not reliably available due to the Plugin being deactivated and going
// through deletion now.

// Get providers.
$providers = get_option( 'wpforms_providers' );

// Bail if no providers exist.
if ( ! $providers ) {
	return;
}

// Bail if no Kit connections exist.
if ( ! array_key_exists( 'convertkit', $providers ) ) {
	return;
}

// Iterate through each connection, revoking the tokens.
foreach ( $providers['convertkit'] as $account_id => $connection ) {
	// Revoke Access Token.
	if ( array_key_exists( 'access_token', $connection ) && ! empty( $connection['access_token'] ) ) {
		wp_remote_post(
			'https://api.kit.com/v4/oauth/revoke',
			array(
				'headers' => array(
					'Accept'       => 'application/json',
					'Content-Type' => 'application/json',
				),
				'body'    => wp_json_encode(
					array(
						'client_id' => 'L0kyADsB3WP5zO5MvUpXQU64gIntQg9BBAIme17r_7A',
						'token'     => $connection['access_token'],
					)
				),
				'timeout' => 5,
			)
		);
	}

	// Revoke Refresh Token.
	if ( array_key_exists( 'refresh_token', $connection ) && ! empty( $connection['refresh_token'] ) ) {
		wp_remote_post(
			'https://api.kit.com/v4/oauth/revoke',
			array(
				'headers' => array(
					'Accept'       => 'application/json',
					'Content-Type' => 'application/json',
				),
				'body'    => wp_json_encode(
					array(
						'client_id' => 'L0kyADsB3WP5zO5MvUpXQU64gIntQg9BBAIme17r_7A',
						'token'     => $connection['refresh_token'],
					)
				),
				'timeout' => 5,
			)
		);
	}

	// Remove credentials from settings.
	$providers['convertkit'][ $account_id ]['access_token']  = '';
	$providers['convertkit'][ $account_id ]['refresh_token'] = '';
	$providers['convertkit'][ $account_id ]['token_expires'] = '';
	$providers['convertkit'][ $account_id ]['api_key']       = '';
	$providers['convertkit'][ $account_id ]['api_secret']    = '';
}

// Save settings.
update_option( 'wpforms_providers', $providers );