<?php
/**
 * Copyright 2010-2013 Amazon.com, Inc. or its affiliates. All Rights Reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License").
 * You may not use this file except in compliance with the License.
 * A copy of the License is located at
 *
 * http://aws.amazon.com/apache2.0
 *
 * or in the "license" file accompanying this file. This file is distributed
 * on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
 * express or implied. See the License for the specific language governing
 * permissions and limitations under the License.
 */

namespace Aws\Common\Signature;

use Aws\Common\Credentials\CredentialsInterface;
use Guzzle\Http\Message\RequestInterface;

/**
 * Interface used to provide interchangeable strategies for signing requests
 * using the various AWS signature protocols.
 */
interface SignatureInterface
{
    /**
     * Signs the specified request with an AWS signing protocol by using the
     * provided AWS account credentials and adding the required headers to the
     * request.
     *
     * @param RequestInterface     $request     Request to add a signature to
     * @param CredentialsInterface $credentials Signing credentials
     */
    public function signRequest(RequestInterface $request, CredentialsInterface $credentials);

    /**
     * Create a pre-signed URL
     *
     * @param RequestInterface     $request Request to sign
     * @param CredentialsInterface $credentials Credentials used to sign
     * @param int|string|\DateTime $expires The time at which the URL should expire. This can be a Unix timestamp, a
     *                                      PHP DateTime object, or a string that can be evaluated by strtotime
     * @return string
     */
    public function createPresignedUrl(
        RequestInterface $request,
        CredentialsInterface $credentials,
        $expires
    );
}
