<?php
/**
 * CheckoutApi_Client_Constant
 * A final class that manage constant value for all CheckoutApi_Client_Client instance
 * @package     CheckoutApi_Client
 * @category     Api
 * @author       Dhiraj Gangoosirdar <dhiraj.gangoosirdar@checkout.com>
 * @copyright 2014 Integration team (http://www.checkout.com)
 */
final class CheckoutApi_Client_Constant 
{
	const APIGW3_URI_PREFIX_PREPOD = 'http://preprod.checkout.com/api2/';
	const APIGW3_URI_PREFIX_DEV= 'http://dev.checkout.com/api2/';
	const APIGW3_URI_PREFIX_SANDBOX= 'http://sandbox.checkout.com/api2/';
	const APIGW3_URI_PREFIX_LIVE = 'https://api2.checkout.com/';
	const ADAPTER_CLASS_GROUP = 'CheckoutApi_Client_Adapter_';
	const PARSER_CLASS_GROUP = 'CheckoutApi_Parser_';
	const CHARGE_TYPE = 'card';
	const LOCALPAYMENT_CHARGE_TYPE = 'localPayment';
	const TOKEN_CARD_TYPE = 'cardToken';
	const TOKEN_SESSION_TYPE = 'sessionToken';
	const AUTOCAPUTURE_CAPTURE = 'y';
	const AUTOCAPUTURE_AUTH = 'n';
	const VERSION = 'v2';
    const STATUS_CAPTURE = 'Captured';
    const STATUS_REFUND = 'Refunded';
    const LIB_VERSION = 'v1.2.5';
}

<?php
/**
 * CheckoutApi_Client_Constant
 * A final class that manage constant value for all CheckoutApi_Client_Client instance
 * @package     CheckoutApi_Client
 * @category     Api
 * @author       Dhiraj Gangoosirdar <dhiraj.gangoosirdar@checkout.com>
 * @copyright 2014 Integration team (http://www.checkout.com)
 */
final class CheckoutApi_Client_Constant 
{
	const APIGW3_URI_PREFIX_PREPOD = 'http://preprod.checkout.com/api2/';
	const APIGW3_URI_PREFIX_DEV= 'http://dev.checkout.com/api2/';
	const APIGW3_URI_PREFIX_SANDBOX= 'https://sandbox.checkout.com/api2/';
	const APIGW3_URI_PREFIX_LIVE = 'https://api2.checkout.com/';
	const ADAPTER_CLASS_GROUP = 'CheckoutApi_Client_Adapter_';
	const PARSER_CLASS_GROUP = 'CheckoutApi_Parser_';
	const CHARGE_TYPE = 'card';
	const LOCALPAYMENT_CHARGE_TYPE = 'localPayment';
	const TOKEN_CARD_TYPE = 'cardToken';
	const TOKEN_SESSION_TYPE = 'sessionToken';
	const AUTOCAPUTURE_CAPTURE = 'y';
	const AUTOCAPUTURE_AUTH = 'n';
	const VERSION = 'v2';
    const STATUS_CAPTURE = 'Captured';
    const STATUS_REFUND = 'Refunded';
    const LIB_VERSION = 'v1.2.5';
}

Change client constants sandbox URL to https
Change client constants sandbox URL to https
