1<?php
2/*
3 * Copyright 2020 Google LLC
4 *
5 * Licensed under the Apache License, Version 2.0 (the "License");
6 * you may not use this file except in compliance with the License.
7 * You may obtain a copy of the License at
8 *
9 *     http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 */
17
18namespace Google\Auth;
19
20/**
21 * Describes a Credentials object which supports updating request metadata
22 * (request headers).
23 */
24interface UpdateMetadataInterface
25{
26    const AUTH_METADATA_KEY = 'authorization';
27
28    /**
29     * Updates metadata with the authorization token.
30     *
31     * @param array<mixed> $metadata metadata hashmap
32     * @param string $authUri optional auth uri
33     * @param callable $httpHandler callback which delivers psr7 request
34     * @return array<mixed> updated metadata hashmap
35     */
36    public function updateMetadata(
37        $metadata,
38        $authUri = null,
39        callable $httpHandler = null
40    );
41}
42