Initial commit

vendor/google/auth/.editorconfig

@@ -0,0 +1,18 @@
+# EditorConfig is awesome: http://EditorConfig.org
+
+# top-most EditorConfig file
+root = true
+charset = utf-8
+
+# Get rid of whitespace to avoid diffs with a bunch of EOL changes
+trim_trailing_whitespace = true
+
+# Unix-style newlines with a newline ending every file
+[*]
+end_of_line = lf
+insert_final_newline = true
+
+# PHP-Files
+[*.php]
+indent_style = space
+indent_size = 4

vendor/google/auth/.github/CONTRIBUTING.md

@@ -0,0 +1,73 @@
+# How to become a contributor and submit your own code
+
+## Contributor License Agreements
+
+We'd love to accept your sample apps and patches! Before we can take them, we
+have to jump a couple of legal hurdles.
+
+Please fill out either the individual or corporate Contributor License Agreement
+(CLA).
+
+  * If you are an individual writing original source code and you're sure you
+    own the intellectual property, then you'll need to sign an [individual CLA]
+    (http://code.google.com/legal/individual-cla-v1.0.html).
+  * If you work for a company that wants to allow you to contribute your work,
+    then you'll need to sign a [corporate CLA]
+    (http://code.google.com/legal/corporate-cla-v1.0.html).
+
+Follow either of the two links above to access the appropriate CLA and
+instructions for how to sign and return it. Once we receive it, we'll be able to
+accept your pull requests.
+
+## Issue reporting
+
+* Check that the issue has not already been reported.
+* Check that the issue has not already been fixed in the latest code
+  (a.k.a. `master`).
+* Be clear, concise and precise in your description of the problem.
+* Open an issue with a descriptive title and a summary in grammatically correct,
+    complete sentences.
+* Include any relevant code to the issue summary.
+
+## Pull requests
+
+* Read [how to properly contribute to open source projects on Github][2].
+* Fork the project.
+* Use a topic/feature branch to easily amend a pull request later, if necessary.
+* Write [good commit messages][3].
+* Use the same coding conventions as the rest of the project.
+* Commit and push until you are happy with your contribution.
+* Make sure to add tests for it. This is important so I don't break it
+  in a future version unintentionally.
+* Add an entry to the [Changelog](CHANGELOG.md) accordingly. See [changelog entry format](#changelog-entry-format).
+* Please try not to mess with the Rakefile, version, or history. If you want to
+  have your own version, or is otherwise necessary, that is fine, but please
+  isolate to its own commit so I can cherry-pick around it.
+* Make sure the test suite is passing and the code you wrote doesn't produce
+  phpunit or phplint offenses.
+* [Squash related commits together][5].
+* Open a [pull request][4] that relates to *only* one subject with a clear title
+  and description in grammatically correct, complete sentences.
+
+### Changelog entry format
+
+Here are a few examples:
+
+```
+* ADC Support for User Refresh Tokens (@tbetbetbe[])
+* [#16](https://github.com/google/google-auth-library-php/issues/16): ADC Support for User Refresh Tokens ([@tbetbetbe][])
+```
+
+* Mark it up in [Markdown syntax][6].
+* The entry line should start with `* ` (an asterisk and a space).
+* If the change has a related GitHub issue (e.g. a bug fix for a reported issue), put a link to the issue as `[#16](https://github.com/google/google-auth-library-php/issues/16): `.
+* Describe the brief of the change. The sentence should end with a punctuation.
+* At the end of the entry, add an implicit link to your GitHub user page as `([@username][])`.
+* If this is your first contribution to google-auth-library-php project, add a link definition for the implicit link to the bottom of the changelog as `[@username]: https://github.com/username`.
+
+[1]: https://github.com/google/google-auth-php-library/issues
+[2]: http://gun.io/blog/how-to-github-fork-branch-and-pull-request
+[3]: http://tbaggery.com/2008/04/19/a-note-about-git-commit-messages.html
+[4]: https://help.github.com/articles/using-pull-requests
+[5]: http://gitready.com/advanced/2009/02/10/squashing-commits-with-rebase.html
+[6]: http://daringfireball.net/projects/markdown/syntax

vendor/google/auth/.github/ISSUE_TEMPLATE/bug_report.md

@@ -0,0 +1,36 @@
+---
+name: Bug report
+about: Create a report to help us improve
+
+---
+
+Thanks for stopping by to let us know something could be better!
+
+**PLEASE READ**: If you have a support contract with Google, please create an issue in the [support console](https://cloud.google.com/support/) instead of filing on GitHub. This will ensure a timely response.
+
+Please run down the following list and make sure you've tried the usual "quick fixes":
+
+  - Search the issues already opened: https://github.com/googleapis/google-auth-library-php/issues
+  - Search StackOverflow: http://stackoverflow.com/questions/tagged/google-cloud-platform+php
+
+If you are still having issues, please be sure to include as much information as possible:
+
+#### Environment details
+
+  - OS:
+  - PHP version:
+  - Package name and version:
+
+#### Steps to reproduce
+
+  1. ...
+
+#### Code example
+
+```php
+# example
+```
+
+Making sure to follow these steps will guarantee the quickest resolution possible.
+
+Thanks!

vendor/google/auth/.github/ISSUE_TEMPLATE/feature_request.md

@@ -0,0 +1,21 @@
+---
+name: Feature request
+about: Suggest an idea for this library
+
+---
+
+Thanks for stopping by to let us know something could be better!
+
+**PLEASE READ**: If you have a support contract with Google, please create an issue in the [support console](https://cloud.google.com/support/) instead of filing on GitHub. This will ensure a timely response.
+
+ **Is your feature request related to a problem? Please describe.**
+A clear and concise description of what the problem is. Ex. I'm always frustrated when [...]
+
+ **Describe the solution you'd like**
+A clear and concise description of what you want to happen.
+
+ **Describe alternatives you've considered**
+A clear and concise description of any alternative solutions or features you've considered.
+
+ **Additional context**
+Add any other context or screenshots about the feature request here.

vendor/google/auth/.github/ISSUE_TEMPLATE/support_request.md

@@ -0,0 +1,7 @@
+---
+name: Support request
+about: If you have a support contract with Google, please create an issue in the Google Cloud Support console.
+
+---
+
+**PLEASE READ**: If you have a support contract with Google, please create an issue in the [support console](https://cloud.google.com/support/) instead of filing on GitHub. This will ensure a timely response.

vendor/google/auth/CHANGELOG.md

@@ -0,0 +1,101 @@
+## 1.5.2 (07/22/2019)
+
+* [fix] Move loadItems call out of `SysVCacheItemPool` constructor. (#229)
+* [fix] Add `Metadata-Flavor` header to initial GCE metadata call. (#232)
+
+## 1.5.1 (04/16/2019)
+
+* [fix] Moved `getClientName()` from `Google\Auth\FetchAuthTokenInterface`
+  to `Google\Auth\SignBlobInterface`, and removed `getClientName()` from
+  `InsecureCredentials` and `UserRefreshCredentials`. (#223)
+
+## 1.5.0 (04/15/2019)
+
+### Changes
+
+ * Add support for signing strings with a Credentials instance. (#221)
+ * [Docs] Describe the arrays returned by fetchAuthToken. (#216)
+ * [Testing] Fix failing tests (#217)
+ * Update GitHub issue templates (#214, #213)
+
+## 1.4.0 (09/17/2018)
+
+### Changes
+
+ * Add support for insecure credentials (#208)
+
+## 1.3.3 (08/27/2018)
+
+### Changes
+
+ * Add retry and increase timeout for GCE credentials (#195)
+ * [Docs] Fix spelling (#204)
+ * Update token url (#206)
+
+## 1.3.2 (07/23/2018)
+
+### Changes
+
+ * Only emits a warning for gcloud credentials (#202)
+
+## 1.3.1 (07/19/2018)
+
+### Changes
+
+ * Added a warning for 3 legged OAuth credentials (#199)
+ * [Code cleanup] Removed useless else after return (#193)
+
+## 1.3.0 (06/04/2018)
+
+### Changes
+
+ * Fixes usage of deprecated env var for GAE Flex (#189)
+ * fix - guzzlehttp/psr7 dependency version definition (#190)
+ * Added SystemV shared memory based CacheItemPool (#191)
+
+## 1.2.1 (24/01/2018)
+
+### Changes
+
+ * Fixes array merging bug in Guzzle5HttpHandler (#186)
+ * Fixes constructor argument bug in Subscriber & Middleware (#184)
+
+## 1.2.0 (6/12/2017)
+
+### Changes
+
+ * Adds async method to HTTP handlers (#176)
+ * Misc bug fixes and improvements (#177, #175, #178)
+
+## 1.1.0 (10/10/2017)
+
+### Changes
+
+ * Supports additional claims in JWT tokens (#171)
+ * Adds makeHttpClient for creating authorized Guzzle clients (#162)
+ * Misc bug fixes/improvements (#168, #161, #167, #170, #143)
+
+## 1.0.1 (31/07/2017)
+
+### Changes
+
+* Adds support for Firebase 5.0 (#159)
+
+## 1.0.0 (12/06/2017)
+
+### Changes
+
+* Adds hashing and shortening to enforce max key length ([@bshaffer])
+* Fix for better PSR-6 compliance - verifies a hit before getting the cache item ([@bshaffer])
+* README fixes ([@bshaffer])
+* Change authorization header key to lowercase ([@stanley-cheung])
+
+## 0.4.0 (23/04/2015)
+
+### Changes
+
+* Export callback function to update auth metadata ([@stanley-cheung][])
+* Adds an implementation of User Refresh Token auth ([@stanley-cheung][])
+
+[@bshaffer]: https://github.com/bshaffer
+[@stanley-cheung]: https://github.com/stanley-cheung

vendor/google/auth/CODE_OF_CONDUCT.md

@@ -0,0 +1,43 @@
+# Contributor Code of Conduct
+
+As contributors and maintainers of this project,
+and in the interest of fostering an open and welcoming community,
+we pledge to respect all people who contribute through reporting issues,
+posting feature requests, updating documentation,
+submitting pull requests or patches, and other activities.
+
+We are committed to making participation in this project
+a harassment-free experience for everyone,
+regardless of level of experience, gender, gender identity and expression,
+sexual orientation, disability, personal appearance,
+body size, race, ethnicity, age, religion, or nationality.
+
+Examples of unacceptable behavior by participants include:
+
+* The use of sexualized language or imagery
+* Personal attacks
+* Trolling or insulting/derogatory comments
+* Public or private harassment
+* Publishing other's private information,
+such as physical or electronic
+addresses, without explicit permission
+* Other unethical or unprofessional conduct.
+
+Project maintainers have the right and responsibility to remove, edit, or reject
+comments, commits, code, wiki edits, issues, and other contributions
+that are not aligned to this Code of Conduct.
+By adopting this Code of Conduct,
+project maintainers commit themselves to fairly and consistently
+applying these principles to every aspect of managing this project.
+Project maintainers who do not follow or enforce the Code of Conduct
+may be permanently removed from the project team.
+
+This code of conduct applies both within project spaces and in public spaces
+when an individual is representing the project or its community.
+
+Instances of abusive, harassing, or otherwise unacceptable behavior
+may be reported by opening an issue
+or contacting one or more of the project maintainers.
+
+This Code of Conduct is adapted from the [Contributor Covenant](http://contributor-covenant.org), version 1.2.0,
+available at [http://contributor-covenant.org/version/1/2/0/](http://contributor-covenant.org/version/1/2/0/)

vendor/google/auth/COPYING

@@ -0,0 +1,202 @@
+
+                                 Apache License
+                           Version 2.0, January 2004
+                        http://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+   1. Definitions.
+
+      "License" shall mean the terms and conditions for use, reproduction,
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+      any Contribution intentionally submitted for inclusion in the Work
+      by You to the Licensor shall be under the terms and conditions of
+      this License, without any additional terms or conditions.
+      Notwithstanding the above, nothing herein shall supersede or modify
+      the terms of any separate license agreement you may have executed
+      with Licensor regarding such Contributions.
+
+   6. Trademarks. This License does not grant permission to use the trade
+      names, trademarks, service marks, or product names of the Licensor,
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+
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+   See the License for the specific language governing permissions and
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vendor/google/auth/LICENSE

@@ -0,0 +1,203 @@
+Apache License
+Version 2.0, January 2004
+http://www.apache.org/licenses/
+
+TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+1. Definitions.
+
+"License" shall mean the terms and conditions for use, reproduction,
+and distribution as defined by Sections 1 through 9 of this document.
+
+"Licensor" shall mean the copyright owner or entity authorized by
+the copyright owner that is granting the License.
+
+"Legal Entity" shall mean the union of the acting entity and all
+other entities that control, are controlled by, or are under common
+control with that entity. For the purposes of this definition,
+"control" means (i) the power, direct or indirect, to cause the
+direction or management of such entity, whether by contract or
+otherwise, or (ii) ownership of fifty percent (50%) or more of the
+outstanding shares, or (iii) beneficial ownership of such entity.
+
+"You" (or "Your") shall mean an individual or Legal Entity
+exercising permissions granted by this License.
+
+"Source" form shall mean the preferred form for making modifications,
+including but not limited to software source code, documentation
+source, and configuration files.
+
+"Object" form shall mean any form resulting from mechanical
+transformation or translation of a Source form, including but
+not limited to compiled object code, generated documentation,
+and conversions to other media types.
+
+"Work" shall mean the work of authorship, whether in Source or
+Object form, made available under the License, as indicated by a
+copyright notice that is included in or attached to the work
+(an example is provided in the Appendix below).
+
+"Derivative Works" shall mean any work, whether in Source or Object
+form, that is based on (or derived from) the Work and for which the
+editorial revisions, annotations, elaborations, or other modifications
+represent, as a whole, an original work of authorship. For the purposes
+of this License, Derivative Works shall not include works that remain
+separable from, or merely link (or bind by name) to the interfaces of,
+the Work and Derivative Works thereof.
+
+"Contribution" shall mean any work of authorship, including
+the original version of the Work and any modifications or additions
+to that Work or Derivative Works thereof, that is intentionally
+submitted to Licensor for inclusion in the Work by the copyright owner
+or by an individual or Legal Entity authorized to submit on behalf of
+the copyright owner. For the purposes of this definition, "submitted"
+means any form of electronic, verbal, or written communication sent
+to the Licensor or its representatives, including but not limited to
+communication on electronic mailing lists, source code control systems,
+and issue tracking systems that are managed by, or on behalf of, the
+Licensor for the purpose of discussing and improving the Work, but
+excluding communication that is conspicuously marked or otherwise
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+
+"Contributor" shall mean Licensor and any individual or Legal Entity
+on behalf of whom a Contribution has been received by Licensor and
+subsequently incorporated within the Work.
+
+2. Grant of Copyright License. Subject to the terms and conditions of
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+worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+copyright license to reproduce, prepare Derivative Works of,
+publicly display, publicly perform, sublicense, and distribute the
+Work and such Derivative Works in Source or Object form.
+
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+worldwide, non-exclusive, no-charge, royalty-free, irrevocable
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+modifications, and in Source or Object form, provided that You
+meet the following conditions:
+
+(a) You must give any other recipients of the Work or
+Derivative Works a copy of this License; and
+
+(b) You must cause any modified files to carry prominent notices
+stating that You changed the files; and
+
+(c) You must retain, in the Source form of any Derivative Works
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+
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+
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+
+

vendor/google/auth/README.md

@@ -0,0 +1,150 @@
+# Google Auth Library for PHP
+
+<dl>
+  <dt>Homepage</dt><dd><a href="http://www.github.com/google/google-auth-library-php">http://www.github.com/google/google-auth-library-php</a></dd>
+  <dt>Authors</dt>
+    <dd><a href="mailto:temiola@google.com">Tim Emiola</a></dd>
+    <dd><a href="mailto:stanleycheung@google.com">Stanley Cheung</a></dd>
+    <dd><a href="mailto:betterbrent@google.com">Brent Shaffer</a></dd>
+  <dt>Copyright</dt><dd>Copyright © 2015 Google, Inc.</dd>
+  <dt>License</dt><dd>Apache 2.0</dd>
+</dl>
+
+## Description
+
+This is Google's officially supported PHP client library for using OAuth 2.0
+authorization and authentication with Google APIs.
+
+### Installing via Composer
+
+The recommended way to install the google auth library is through
+[Composer](http://getcomposer.org).
+
+```bash
+# Install Composer
+curl -sS https://getcomposer.org/installer | php
+```
+
+Next, run the Composer command to install the latest stable version:
+
+```bash
+composer.phar require google/auth
+```
+
+## Application Default Credentials
+
+This library provides an implementation of
+[application default credentials][application default credentials] for PHP.
+
+The Application Default Credentials provide a simple way to get authorization
+credentials for use in calling Google APIs.
+
+They are best suited for cases when the call needs to have the same identity
+and authorization level for the application independent of the user. This is
+the recommended approach to authorize calls to Cloud APIs, particularly when
+you're building an application that uses Google Compute Engine.
+
+#### Download your Service Account Credentials JSON file
+
+To use `Application Default Credentials`, You first need to download a set of
+JSON credentials for your project. Go to **APIs & Auth** > **Credentials** in
+the [Google Developers Console][developer console] and select
+**Service account** from the **Add credentials** dropdown.
+
+> This file is your *only copy* of these credentials. It should never be
+> committed with your source code, and should be stored securely.
+
+Once downloaded, store the path to this file in the
+`GOOGLE_APPLICATION_CREDENTIALS` environment variable.
+
+```php
+putenv('GOOGLE_APPLICATION_CREDENTIALS=/path/to/my/credentials.json');
+```
+
+> PHP's `putenv` function is just one way to set an environment variable.
+> Consider using `.htaccess` or apache configuration files as well.
+
+#### Enable the API you want to use
+
+Before making your API call, you must be sure the API you're calling has been
+enabled. Go to **APIs & Auth** > **APIs** in the
+[Google Developers Console][developer console] and enable the APIs you'd like to
+call. For the example below, you must enable the `Drive API`.
+
+#### Call the APIs
+
+As long as you update the environment variable below to point to *your* JSON
+credentials file, the following code should output a list of your Drive files.
+
+```php
+use Google\Auth\ApplicationDefaultCredentials;
+use GuzzleHttp\Client;
+use GuzzleHttp\HandlerStack;
+
+// specify the path to your application credentials
+putenv('GOOGLE_APPLICATION_CREDENTIALS=/path/to/my/credentials.json');
+
+// define the scopes for your API call
+$scopes = ['https://www.googleapis.com/auth/drive.readonly'];
+
+// create middleware
+$middleware = ApplicationDefaultCredentials::getMiddleware($scopes);
+$stack = HandlerStack::create();
+$stack->push($middleware);
+
+// create the HTTP client
+$client = new Client([
+  'handler' => $stack,
+  'base_uri' => 'https://www.googleapis.com',
+  'auth' => 'google_auth'  // authorize all requests
+]);
+
+// make the request
+$response = $client->get('drive/v2/files');
+
+// show the result!
+print_r((string) $response->getBody());
+```
+
+##### Guzzle 5 Compatibility
+
+If you are using [Guzzle 5][Guzzle 5], replace the `create middleware` and
+`create the HTTP Client` steps with the following:
+
+```php
+// create the HTTP client
+$client = new Client([
+  'base_url' => 'https://www.googleapis.com',
+  'auth' => 'google_auth'  // authorize all requests
+]);
+
+// create subscriber
+$subscriber = ApplicationDefaultCredentials::getSubscriber($scopes);
+$client->getEmitter()->attach($subscriber);
+
+```
+
+## License
+
+This library is licensed under Apache 2.0. Full license text is
+available in [COPYING][copying].
+
+## Contributing
+
+See [CONTRIBUTING][contributing].
+
+## Support
+
+Please
+[report bugs at the project on Github](https://github.com/google/google-auth-library-php/issues). Don't
+hesitate to
+[ask questions](http://stackoverflow.com/questions/tagged/google-auth-library-php)
+about the client or APIs on [StackOverflow](http://stackoverflow.com).
+
+[google-apis-php-client]: https://github.com/google/google-api-php-client
+[application default credentials]: https://developers.google.com/accounts/docs/application-default-credentials
+[contributing]: https://github.com/google/google-auth-library-php/tree/master/.github/CONTRIBUTING.md
+[copying]: https://github.com/google/google-auth-library-php/tree/master/COPYING
+[Guzzle]: https://github.com/guzzle/guzzle
+[Guzzle 5]: http://docs.guzzlephp.org/en/5.3
+[developer console]: https://console.developers.google.com

vendor/google/auth/autoload.php

@@ -0,0 +1,34 @@
+<?php
+/*
+ * Copyright 2014 Google Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License 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.
+ */
+
+function oauth2client_php_autoload($className)
+{
+    $classPath = explode('_', $className);
+    if ($classPath[0] != 'Google') {
+        return;
+    }
+    if (count($classPath) > 3) {
+        // Maximum class file path depth in this project is 3.
+    $classPath = array_slice($classPath, 0, 3);
+    }
+    $filePath = dirname(__FILE__) . '/src/' . implode('/', $classPath) . '.php';
+    if (file_exists($filePath)) {
+        require_once $filePath;
+    }
+}
+
+spl_autoload_register('oauth2client_php_autoload');

vendor/google/auth/composer.json

@@ -0,0 +1,31 @@
+{
+  "name": "google/auth",
+  "type": "library",
+  "description": "Google Auth Library for PHP",
+  "keywords": ["google", "oauth2", "authentication"],
+  "homepage": "http://github.com/google/google-auth-library-php",
+  "license": "Apache-2.0",
+  "require": {
+    "php": ">=5.4",
+    "firebase/php-jwt": "~2.0|~3.0|~4.0|~5.0",
+    "guzzlehttp/guzzle": "~5.3.1|~6.0",
+    "guzzlehttp/psr7": "^1.2",
+    "psr/http-message": "^1.0",
+    "psr/cache": "^1.0"
+  },
+  "require-dev": {
+    "guzzlehttp/promises": "0.1.1|^1.3",
+    "friendsofphp/php-cs-fixer": "^1.11",
+    "phpunit/phpunit": "^4.8.36|^5.7",
+    "sebastian/comparator": ">=1.2.3",
+    "phpseclib/phpseclib": "^2"
+  },
+  "suggest": {
+    "phpseclib/phpseclib": "May be used in place of OpenSSL for signing strings. Please require version ^2."
+  },
+  "autoload": {
+    "psr-4": {
+      "Google\\Auth\\": "src"
+    }
+  }
+}

vendor/google/auth/src/ApplicationDefaultCredentials.php

@@ -0,0 +1,185 @@
+<?php
+/*
+ * Copyright 2015 Google Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License 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 Google\Auth;
+
+use DomainException;
+use Google\Auth\Credentials\AppIdentityCredentials;
+use Google\Auth\Credentials\GCECredentials;
+use Google\Auth\HttpHandler\HttpClientCache;
+use Google\Auth\HttpHandler\HttpHandlerFactory;
+use Google\Auth\Middleware\AuthTokenMiddleware;
+use Google\Auth\Subscriber\AuthTokenSubscriber;
+use GuzzleHttp\Client;
+use Psr\Cache\CacheItemPoolInterface;
+
+/**
+ * ApplicationDefaultCredentials obtains the default credentials for
+ * authorizing a request to a Google service.
+ *
+ * Application Default Credentials are described here:
+ * https://developers.google.com/accounts/docs/application-default-credentials
+ *
+ * This class implements the search for the application default credentials as
+ * described in the link.
+ *
+ * It provides three factory methods:
+ * - #get returns the computed credentials object
+ * - #getSubscriber returns an AuthTokenSubscriber built from the credentials object
+ * - #getMiddleware returns an AuthTokenMiddleware built from the credentials object
+ *
+ * This allows it to be used as follows with GuzzleHttp\Client:
+ *
+ *   use Google\Auth\ApplicationDefaultCredentials;
+ *   use GuzzleHttp\Client;
+ *   use GuzzleHttp\HandlerStack;
+ *
+ *   $middleware = ApplicationDefaultCredentials::getMiddleware(
+ *       'https://www.googleapis.com/auth/taskqueue'
+ *   );
+ *   $stack = HandlerStack::create();
+ *   $stack->push($middleware);
+ *
+ *   $client = new Client([
+ *       'handler' => $stack,
+ *       'base_uri' => 'https://www.googleapis.com/taskqueue/v1beta2/projects/',
+ *       'auth' => 'google_auth' // authorize all requests
+ *   ]);
+ *
+ *   $res = $client->get('myproject/taskqueues/myqueue');
+ */
+class ApplicationDefaultCredentials
+{
+    /**
+     * Obtains an AuthTokenSubscriber that uses the default FetchAuthTokenInterface
+     * implementation to use in this environment.
+     *
+     * If supplied, $scope is used to in creating the credentials instance if
+     * this does not fallback to the compute engine defaults.
+     *
+     * @param string|array scope the scope of the access request, expressed
+     *   either as an Array or as a space-delimited String.
+     * @param callable $httpHandler callback which delivers psr7 request
+     * @param array $cacheConfig configuration for the cache when it's present
+     * @param CacheItemPoolInterface $cache an implementation of CacheItemPoolInterface
+     *
+     * @return AuthTokenSubscriber
+     *
+     * @throws DomainException if no implementation can be obtained.
+     */
+    public static function getSubscriber(
+        $scope = null,
+        callable $httpHandler = null,
+        array $cacheConfig = null,
+        CacheItemPoolInterface $cache = null
+    ) {
+        $creds = self::getCredentials($scope, $httpHandler, $cacheConfig, $cache);
+
+        return new AuthTokenSubscriber($creds, $httpHandler);
+    }
+
+    /**
+     * Obtains an AuthTokenMiddleware that uses the default FetchAuthTokenInterface
+     * implementation to use in this environment.
+     *
+     * If supplied, $scope is used to in creating the credentials instance if
+     * this does not fallback to the compute engine defaults.
+     *
+     * @param string|array scope the scope of the access request, expressed
+     *   either as an Array or as a space-delimited String.
+     * @param callable $httpHandler callback which delivers psr7 request
+     * @param array $cacheConfig configuration for the cache when it's present
+     * @param CacheItemPoolInterface $cache
+     *
+     * @return AuthTokenMiddleware
+     *
+     * @throws DomainException if no implementation can be obtained.
+     */
+    public static function getMiddleware(
+        $scope = null,
+        callable $httpHandler = null,
+        array $cacheConfig = null,
+        CacheItemPoolInterface $cache = null
+    ) {
+        $creds = self::getCredentials($scope, $httpHandler, $cacheConfig, $cache);
+
+        return new AuthTokenMiddleware($creds, $httpHandler);
+    }
+
+    /**
+     * Obtains the default FetchAuthTokenInterface implementation to use
+     * in this environment.
+     *
+     * If supplied, $scope is used to in creating the credentials instance if
+     * this does not fallback to the Compute Engine defaults.
+     *
+     * @param string|array scope the scope of the access request, expressed
+     *   either as an Array or as a space-delimited String.
+     * @param callable $httpHandler callback which delivers psr7 request
+     * @param array $cacheConfig configuration for the cache when it's present
+     * @param CacheItemPoolInterface $cache
+     *
+     * @return CredentialsLoader
+     *
+     * @throws DomainException if no implementation can be obtained.
+     */
+    public static function getCredentials(
+        $scope = null,
+        callable $httpHandler = null,
+        array $cacheConfig = null,
+        CacheItemPoolInterface $cache = null
+    ) {
+        $creds = null;
+        $jsonKey = CredentialsLoader::fromEnv()
+            ?: CredentialsLoader::fromWellKnownFile();
+
+        if (!$httpHandler) {
+            if (!($client = HttpClientCache::getHttpClient())) {
+                $client = new Client();
+                HttpClientCache::setHttpClient($client);
+            }
+
+            $httpHandler = HttpHandlerFactory::build($client);
+        }
+
+        if (!is_null($jsonKey)) {
+            $creds = CredentialsLoader::makeCredentials($scope, $jsonKey);
+        } elseif (AppIdentityCredentials::onAppEngine() && !GCECredentials::onAppEngineFlexible()) {
+            $creds = new AppIdentityCredentials($scope);
+        } elseif (GCECredentials::onGce($httpHandler)) {
+            $creds = new GCECredentials();
+        }
+
+        if (is_null($creds)) {
+            throw new \DomainException(self::notFound());
+        }
+        if (!is_null($cache)) {
+            $creds = new FetchAuthTokenCache($creds, $cacheConfig, $cache);
+        }
+        return $creds;
+    }
+
+    private static function notFound()
+    {
+        $msg = 'Could not load the default credentials. Browse to ';
+        $msg .= 'https://developers.google.com';
+        $msg .= '/accounts/docs/application-default-credentials';
+        $msg .= ' for more information';
+
+        return $msg;
+    }
+}

vendor/google/auth/src/Cache/InvalidArgumentException.php

@@ -0,0 +1,24 @@
+<?php
+/*
+ * Copyright 2016 Google Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License 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 Google\Auth\Cache;
+
+use Psr\Cache\InvalidArgumentException as PsrInvalidArgumentException;
+
+class InvalidArgumentException extends \InvalidArgumentException implements PsrInvalidArgumentException
+{
+}

vendor/google/auth/src/Cache/Item.php

@@ -0,0 +1,185 @@
+<?php
+/*
+ * Copyright 2016 Google Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License 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 Google\Auth\Cache;
+
+use Psr\Cache\CacheItemInterface;
+
+/**
+ * A cache item.
+ */
+final class Item implements CacheItemInterface
+{
+    /**
+     * @var string
+     */
+    private $key;
+
+    /**
+     * @var mixed
+     */
+    private $value;
+
+    /**
+     * @var \DateTime
+     */
+    private $expiration;
+
+    /**
+     * @var bool
+     */
+    private $isHit = false;
+
+    /**
+     * @param string $key
+     */
+    public function __construct($key)
+    {
+        $this->key = $key;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function getKey()
+    {
+        return $this->key;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function get()
+    {
+        return $this->isHit() ? $this->value : null;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function isHit()
+    {
+        if (!$this->isHit) {
+            return false;
+        }
+
+        if ($this->expiration === null) {
+            return true;
+        }
+
+        return new \DateTime() < $this->expiration;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function set($value)
+    {
+        $this->isHit = true;
+        $this->value = $value;
+
+        return $this;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function expiresAt($expiration)
+    {
+        if ($this->isValidExpiration($expiration)) {
+            $this->expiration = $expiration;
+
+            return $this;
+        }
+
+        $implementationMessage = interface_exists('DateTimeInterface')
+            ? 'implement interface DateTimeInterface'
+            : 'be an instance of DateTime';
+
+        $error = sprintf(
+            'Argument 1 passed to %s::expiresAt() must %s, %s given',
+            get_class($this),
+            $implementationMessage,
+            gettype($expiration)
+        );
+
+        $this->handleError($error);
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function expiresAfter($time)
+    {
+        if (is_int($time)) {
+            $this->expiration = new \DateTime("now + $time seconds");
+        } elseif ($time instanceof \DateInterval) {
+            $this->expiration = (new \DateTime())->add($time);
+        } elseif ($time === null) {
+            $this->expiration = $time;
+        } else {
+            $message = 'Argument 1 passed to %s::expiresAfter() must be an ' .
+                       'instance of DateInterval or of the type integer, %s given';
+            $error = sprintf($message, get_class($this), gettype($time));
+
+            $this->handleError($error);
+        }
+
+        return $this;
+    }
+
+    /**
+     * Handles an error.
+     *
+     * @param string $error
+     * @throws \TypeError
+     */
+    private function handleError($error)
+    {
+        if (class_exists('TypeError')) {
+            throw new \TypeError($error);
+        }
+
+        trigger_error($error, E_USER_ERROR);
+    }
+
+    /**
+     * Determines if an expiration is valid based on the rules defined by PSR6.
+     *
+     * @param mixed $expiration
+     * @return bool
+     */
+    private function isValidExpiration($expiration)
+    {
+        if ($expiration === null) {
+            return true;
+        }
+
+        // We test for two types here due to the fact the DateTimeInterface
+        // was not introduced until PHP 5.5. Checking for the DateTime type as
+        // well allows us to support 5.4.
+        if ($expiration instanceof \DateTimeInterface) {
+            return true;
+        }
+
+        if ($expiration instanceof \DateTime) {
+            return true;
+        }
+
+        return false;
+    }
+}

vendor/google/auth/src/Cache/MemoryCacheItemPool.php

@@ -0,0 +1,154 @@
+<?php
+/*
+ * Copyright 2016 Google Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License 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 Google\Auth\Cache;
+
+use Psr\Cache\CacheItemInterface;
+use Psr\Cache\CacheItemPoolInterface;
+
+/**
+ * Simple in-memory cache implementation.
+ */
+final class MemoryCacheItemPool implements CacheItemPoolInterface
+{
+    /**
+     * @var CacheItemInterface[]
+     */
+    private $items;
+
+    /**
+     * @var CacheItemInterface[]
+     */
+    private $deferredItems;
+
+    /**
+     * {@inheritdoc}
+     */
+    public function getItem($key)
+    {
+        return current($this->getItems([$key]));
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function getItems(array $keys = [])
+    {
+        $items = [];
+
+        foreach ($keys as $key) {
+            $items[$key] = $this->hasItem($key) ? clone $this->items[$key] : new Item($key);
+        }
+
+        return $items;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function hasItem($key)
+    {
+        $this->isValidKey($key);
+
+        return isset($this->items[$key]) && $this->items[$key]->isHit();
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function clear()
+    {
+        $this->items = [];
+        $this->deferredItems = [];
+
+        return true;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function deleteItem($key)
+    {
+        return $this->deleteItems([$key]);
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function deleteItems(array $keys)
+    {
+        array_walk($keys, [$this, 'isValidKey']);
+
+        foreach ($keys as $key) {
+            unset($this->items[$key]);
+        }
+
+        return true;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function save(CacheItemInterface $item)
+    {
+        $this->items[$item->getKey()] = $item;
+
+        return true;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function saveDeferred(CacheItemInterface $item)
+    {
+        $this->deferredItems[$item->getKey()] = $item;
+
+        return true;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function commit()
+    {
+        foreach ($this->deferredItems as $item) {
+            $this->save($item);
+        }
+
+        $this->deferredItems = [];
+
+        return true;
+    }
+
+    /**
+     * Determines if the provided key is valid.
+     *
+     * @param string $key
+     * @return bool
+     * @throws InvalidArgumentException
+     */
+    private function isValidKey($key)
+    {
+        $invalidCharacters = '{}()/\\\\@:';
+
+        if (!is_string($key) || preg_match("#[$invalidCharacters]#", $key)) {
+            throw new InvalidArgumentException('The provided key is not valid: ' . var_export($key, true));
+        }
+
+        return true;
+    }
+}

vendor/google/auth/src/Cache/SysVCacheItemPool.php

@@ -0,0 +1,244 @@
+<?php
+/**
+ * Copyright 2018 Google Inc. 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.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License 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 Google\Auth\Cache;
+
+use Psr\Cache\CacheItemInterface;
+use Psr\Cache\CacheItemPoolInterface;
+
+/**
+ * SystemV shared memory based CacheItemPool implementation.
+ *
+ * This CacheItemPool implementation can be used among multiple processes, but
+ * it doesn't provide any locking mechanism. If multiple processes write to
+ * this ItemPool, you have to avoid race condition manually in your code.
+ */
+class SysVCacheItemPool implements CacheItemPoolInterface
+{
+    const VAR_KEY = 1;
+
+    const DEFAULT_PROJ = 'A';
+
+    const DEFAULT_MEMSIZE = 10000;
+
+    const DEFAULT_PERM = 0600;
+
+    /** @var int */
+    private $sysvKey;
+
+    /**
+     * @var CacheItemInterface[]
+     */
+    private $items;
+
+    /**
+     * @var CacheItemInterface[]
+     */
+    private $deferredItems;
+
+    /**
+     * @var array
+     */
+    private $options;
+
+    /*
+     * @var bool
+     */
+    private $hasLoadedItems = false;
+
+    /**
+     * Create a SystemV shared memory based CacheItemPool.
+     *
+     * @param array $options [optional] {
+     *     Configuration options.
+     *
+     *     @type int $variableKey The variable key for getting the data from
+     *           the shared memory. **Defaults to** 1.
+     *     @type string $proj The project identifier for ftok. This needs to
+     *           be a one character string. **Defaults to** 'A'.
+     *     @type int $memsize The memory size in bytes for shm_attach.
+     *           **Defaults to** 10000.
+     *     @type int $perm The permission for shm_attach. **Defaults to** 0600.
+     */
+    public function __construct($options = [])
+    {
+        if (! extension_loaded('sysvshm')) {
+            throw \RuntimeException(
+                'sysvshm extension is required to use this ItemPool');
+        }
+        $this->options = $options + [
+            'variableKey' => self::VAR_KEY,
+            'proj' => self::DEFAULT_PROJ,
+            'memsize' => self::DEFAULT_MEMSIZE,
+            'perm' => self::DEFAULT_PERM
+        ];
+        $this->items = [];
+        $this->deferredItems = [];
+        $this->sysvKey = ftok(__FILE__, $this->options['proj']);
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function getItem($key)
+    {
+        $this->loadItems();
+        return current($this->getItems([$key]));
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function getItems(array $keys = [])
+    {
+        $this->loadItems();
+        $items = [];
+        foreach ($keys as $key) {
+            $items[$key] = $this->hasItem($key) ?
+                clone $this->items[$key] :
+                new Item($key);
+        }
+        return $items;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function hasItem($key)
+    {
+        $this->loadItems();
+        return isset($this->items[$key]) && $this->items[$key]->isHit();
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function clear()
+    {
+        $this->items = [];
+        $this->deferredItems = [];
+        return $this->saveCurrentItems();
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function deleteItem($key)
+    {
+        return $this->deleteItems([$key]);
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function deleteItems(array $keys)
+    {
+        if (!$this->hasLoadedItems) {
+            $this->loadItems();
+        }
+
+        foreach ($keys as $key) {
+            unset($this->items[$key]);
+        }
+        return $this->saveCurrentItems();
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function save(CacheItemInterface $item)
+    {
+        if (!$this->hasLoadedItems) {
+            $this->loadItems();
+        }
+
+        $this->items[$item->getKey()] = $item;
+        return $this->saveCurrentItems();
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function saveDeferred(CacheItemInterface $item)
+    {
+        $this->deferredItems[$item->getKey()] = $item;
+        return true;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function commit()
+    {
+        foreach ($this->deferredItems as $item) {
+            if ($this->save($item) === false) {
+                return false;
+            }
+        }
+        $this->deferredItems = [];
+        return true;
+    }
+
+    /**
+     * Save the current items.
+     *
+     * @return bool true when success, false upon failure
+     */
+    private function saveCurrentItems()
+    {
+        $shmid = shm_attach(
+            $this->sysvKey,
+            $this->options['memsize'],
+            $this->options['perm']
+        );
+        if ($shmid !== false) {
+            $ret = shm_put_var(
+                $shmid,
+                $this->options['variableKey'],
+                $this->items
+            );
+            shm_detach($shmid);
+            return $ret;
+        }
+        return false;
+    }
+
+    /**
+     * Load the items from the shared memory.
+     *
+     * @return bool true when success, false upon failure
+     */
+    private function loadItems()
+    {
+        $shmid = shm_attach(
+            $this->sysvKey,
+            $this->options['memsize'],
+            $this->options['perm']
+        );
+        if ($shmid !== false) {
+            $data = @shm_get_var($shmid, $this->options['variableKey']);
+            if (!empty($data)) {
+                $this->items = $data;
+            } else {
+                $this->items = [];
+            }
+            shm_detach($shmid);
+            $this->hasLoadedItems = true;
+            return true;
+        }
+        return false;
+    }
+}

vendor/google/auth/src/CacheTrait.php

@@ -0,0 +1,83 @@
+<?php
+/*
+ * Copyright 2015 Google Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License 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 Google\Auth;
+
+trait CacheTrait
+{
+    private $maxKeyLength = 64;
+
+    /**
+     * Gets the cached value if it is present in the cache when that is
+     * available.
+     */
+    private function getCachedValue($k)
+    {
+        if (is_null($this->cache)) {
+            return;
+        }
+
+        $key = $this->getFullCacheKey($k);
+        if (is_null($key)) {
+            return;
+        }
+
+        $cacheItem = $this->cache->getItem($key);
+        if ($cacheItem->isHit()) {
+            return $cacheItem->get();
+        }
+    }
+
+    /**
+     * Saves the value in the cache when that is available.
+     */
+    private function setCachedValue($k, $v)
+    {
+        if (is_null($this->cache)) {
+            return;
+        }
+
+        $key = $this->getFullCacheKey($k);
+        if (is_null($key)) {
+            return;
+        }
+
+        $cacheItem = $this->cache->getItem($key);
+        $cacheItem->set($v);
+        $cacheItem->expiresAfter($this->cacheConfig['lifetime']);
+        return $this->cache->save($cacheItem);
+    }
+
+    private function getFullCacheKey($key)
+    {
+        if (is_null($key)) {
+            return;
+        }
+
+        $key = $this->cacheConfig['prefix'] . $key;
+
+        // ensure we do not have illegal characters
+        $key = preg_replace('|[^a-zA-Z0-9_\.!]|', '', $key);
+
+        // Hash keys if they exceed $maxKeyLength (defaults to 64)
+        if ($this->maxKeyLength && strlen($key) > $this->maxKeyLength) {
+            $key = substr(hash('sha256', $key), 0, $this->maxKeyLength);
+        }
+
+        return $key;
+    }
+}

vendor/google/auth/src/Credentials/AppIdentityCredentials.php

@@ -0,0 +1,201 @@
+<?php
+/*
+ * Copyright 2015 Google Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License 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 Google\Auth\Credentials;
+
+/*
+ * The AppIdentityService class is automatically defined on App Engine,
+ * so including this dependency is not necessary, and will result in a
+ * PHP fatal error in the App Engine environment.
+ */
+use google\appengine\api\app_identity\AppIdentityService;
+use Google\Auth\CredentialsLoader;
+use Google\Auth\SignBlobInterface;
+
+/**
+ * AppIdentityCredentials supports authorization on Google App Engine.
+ *
+ * It can be used to authorize requests using the AuthTokenMiddleware or
+ * AuthTokenSubscriber, but will only succeed if being run on App Engine:
+ *
+ *   use Google\Auth\Credentials\AppIdentityCredentials;
+ *   use Google\Auth\Middleware\AuthTokenMiddleware;
+ *   use GuzzleHttp\Client;
+ *   use GuzzleHttp\HandlerStack;
+ *
+ *   $gae = new AppIdentityCredentials('https://www.googleapis.com/auth/books');
+ *   $middleware = new AuthTokenMiddleware($gae);
+ *   $stack = HandlerStack::create();
+ *   $stack->push($middleware);
+ *
+ *   $client = new Client([
+ *       'handler' => $stack,
+ *       'base_uri' => 'https://www.googleapis.com/books/v1',
+ *       'auth' => 'google_auth'
+ *   ]);
+ *
+ *   $res = $client->get('volumes?q=Henry+David+Thoreau&country=US');
+ */
+class AppIdentityCredentials extends CredentialsLoader implements SignBlobInterface
+{
+    /**
+     * Result of fetchAuthToken.
+     *
+     * @array
+     */
+    protected $lastReceivedToken;
+
+    /**
+     * Array of OAuth2 scopes to be requested.
+     */
+    private $scope;
+
+    /**
+     * @var string
+     */
+    private $clientName;
+
+    public function __construct($scope = array())
+    {
+        $this->scope = $scope;
+    }
+
+    /**
+     * Determines if this an App Engine instance, by accessing the
+     * SERVER_SOFTWARE environment variable (prod) or the APPENGINE_RUNTIME
+     * environment variable (dev).
+     *
+     * @return true if this an App Engine Instance, false otherwise
+     */
+    public static function onAppEngine()
+    {
+        $appEngineProduction = isset($_SERVER['SERVER_SOFTWARE']) &&
+            0 === strpos($_SERVER['SERVER_SOFTWARE'], 'Google App Engine');
+        if ($appEngineProduction) {
+            return true;
+        }
+        $appEngineDevAppServer = isset($_SERVER['APPENGINE_RUNTIME']) &&
+            $_SERVER['APPENGINE_RUNTIME'] == 'php';
+        if ($appEngineDevAppServer) {
+            return true;
+        }
+        return false;
+    }
+
+    /**
+     * Implements FetchAuthTokenInterface#fetchAuthToken.
+     *
+     * Fetches the auth tokens using the AppIdentityService if available.
+     * As the AppIdentityService uses protobufs to fetch the access token,
+     * the GuzzleHttp\ClientInterface instance passed in will not be used.
+     *
+     * @param callable $httpHandler callback which delivers psr7 request
+     *
+     * @return array A set of auth related metadata, containing the following
+     *     keys:
+     *         - access_token (string)
+     *         - expiration_time (string)
+     */
+    public function fetchAuthToken(callable $httpHandler = null)
+    {
+        try {
+            $this->checkAppEngineContext();
+        } catch (\Exception $e) {
+            return [];
+        }
+
+        // AppIdentityService expects an array when multiple scopes are supplied
+        $scope = is_array($this->scope) ? $this->scope : explode(' ', $this->scope);
+
+        $token = AppIdentityService::getAccessToken($scope);
+        $this->lastReceivedToken = $token;
+
+        return $token;
+    }
+
+    /**
+     * Sign a string using AppIdentityService.
+     *
+     * @param string $stringToSign The string to sign.
+     * @param bool $forceOpenSsl [optional] Does not apply to this credentials
+     *        type.
+     * @return string The signature, base64-encoded.
+     * @throws \Exception If AppEngine SDK or mock is not available.
+     */
+    public function signBlob($stringToSign, $forceOpenSsl = false)
+    {
+        $this->checkAppEngineContext();
+
+        return base64_encode(AppIdentityService::signForApp($stringToSign)['signature']);
+    }
+
+    /**
+     * Get the client name from AppIdentityService.
+     *
+     * Subsequent calls to this method will return a cached value.
+     *
+     * @param callable $httpHandler Not used in this implementation.
+     * @return string
+     * @throws \Exception If AppEngine SDK or mock is not available.
+     */
+    public function getClientName(callable $httpHandler = null)
+    {
+        $this->checkAppEngineContext();
+
+        if (!$this->clientName) {
+            $this->clientName = AppIdentityService::getServiceAccountName();
+        }
+
+        return $this->clientName;
+    }
+
+    /**
+     * @return array|null
+     */
+    public function getLastReceivedToken()
+    {
+        if ($this->lastReceivedToken) {
+            return [
+                'access_token' => $this->lastReceivedToken['access_token'],
+                'expires_at' => $this->lastReceivedToken['expiration_time'],
+            ];
+        }
+
+        return null;
+    }
+
+    /**
+     * Caching is handled by the underlying AppIdentityService, return empty string
+     * to prevent caching.
+     *
+     * @return string
+     */
+    public function getCacheKey()
+    {
+        return '';
+    }
+
+    private function checkAppEngineContext()
+    {
+        if (!self::onAppEngine() || !class_exists('google\appengine\api\app_identity\AppIdentityService')) {
+            throw new \Exception(
+                'This class must be run in App Engine, or you must include the AppIdentityService '
+                . 'mock class defined in tests/mocks/AppIdentityService.php'
+            );
+        }
+    }
+}

vendor/google/auth/src/Credentials/GCECredentials.php

@@ -0,0 +1,353 @@
+<?php
+/*
+ * Copyright 2015 Google Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License 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 Google\Auth\Credentials;
+
+use Google\Auth\CredentialsLoader;
+use Google\Auth\HttpHandler\HttpClientCache;
+use Google\Auth\HttpHandler\HttpHandlerFactory;
+use Google\Auth\Iam;
+use Google\Auth\SignBlobInterface;
+use GuzzleHttp\Exception\ClientException;
+use GuzzleHttp\Exception\RequestException;
+use GuzzleHttp\Exception\ServerException;
+use GuzzleHttp\Psr7\Request;
+
+/**
+ * GCECredentials supports authorization on Google Compute Engine.
+ *
+ * It can be used to authorize requests using the AuthTokenMiddleware, but will
+ * only succeed if being run on GCE:
+ *
+ *   use Google\Auth\Credentials\GCECredentials;
+ *   use Google\Auth\Middleware\AuthTokenMiddleware;
+ *   use GuzzleHttp\Client;
+ *   use GuzzleHttp\HandlerStack;
+ *
+ *   $gce = new GCECredentials();
+ *   $middleware = new AuthTokenMiddleware($gce);
+ *   $stack = HandlerStack::create();
+ *   $stack->push($middleware);
+ *
+ *   $client = new Client([
+ *      'handler' => $stack,
+ *      'base_uri' => 'https://www.googleapis.com/taskqueue/v1beta2/projects/',
+ *      'auth' => 'google_auth'
+ *   ]);
+ *
+ *   $res = $client->get('myproject/taskqueues/myqueue');
+ */
+class GCECredentials extends CredentialsLoader implements SignBlobInterface
+{
+    const cacheKey = 'GOOGLE_AUTH_PHP_GCE';
+
+    /**
+     * The metadata IP address on appengine instances.
+     *
+     * The IP is used instead of the domain 'metadata' to avoid slow responses
+     * when not on Compute Engine.
+     */
+    const METADATA_IP = '169.254.169.254';
+
+    /**
+     * The metadata path of the default token.
+     */
+    const TOKEN_URI_PATH = 'v1/instance/service-accounts/default/token';
+
+    /**
+     * The metadata path of the client ID.
+     */
+    const CLIENT_ID_URI_PATH = 'v1/instance/service-accounts/default/email';
+
+    /**
+     * The header whose presence indicates GCE presence.
+     */
+    const FLAVOR_HEADER = 'Metadata-Flavor';
+
+    /**
+     * Note: the explicit `timeout` and `tries` below is a workaround. The underlying
+     * issue is that resolving an unknown host on some networks will take
+     * 20-30 seconds; making this timeout short fixes the issue, but
+     * could lead to false negatives in the event that we are on GCE, but
+     * the metadata resolution was particularly slow. The latter case is
+     * "unlikely" since the expected 4-nines time is about 0.5 seconds.
+     * This allows us to limit the total ping maximum timeout to 1.5 seconds
+     * for developer desktop scenarios.
+     */
+    const MAX_COMPUTE_PING_TRIES = 3;
+    const COMPUTE_PING_CONNECTION_TIMEOUT_S = 0.5;
+
+    /**
+     * Flag used to ensure that the onGCE test is only done once;.
+     *
+     * @var bool
+     */
+    private $hasCheckedOnGce = false;
+
+    /**
+     * Flag that stores the value of the onGCE check.
+     *
+     * @var bool
+     */
+    private $isOnGce = false;
+
+    /**
+     * Result of fetchAuthToken.
+     */
+    protected $lastReceivedToken;
+
+    /**
+     * @var string
+     */
+    private $clientName;
+
+    /**
+     * @var Iam|null
+     */
+    private $iam;
+
+    /**
+     * @param Iam $iam [optional] An IAM instance.
+     */
+    public function __construct(Iam $iam = null)
+    {
+        $this->iam = $iam;
+    }
+
+    /**
+     * The full uri for accessing the default token.
+     *
+     * @return string
+     */
+    public static function getTokenUri()
+    {
+        $base = 'http://' . self::METADATA_IP . '/computeMetadata/';
+
+        return $base . self::TOKEN_URI_PATH;
+    }
+
+    /**
+     * The full uri for accessing the default service account.
+     *
+     * @return string
+     */
+    public static function getClientNameUri()
+    {
+        $base = 'http://' . self::METADATA_IP . '/computeMetadata/';
+
+        return $base . self::CLIENT_ID_URI_PATH;
+    }
+
+    /**
+     * Determines if this an App Engine Flexible instance, by accessing the
+     * GAE_INSTANCE environment variable.
+     *
+     * @return true if this an App Engine Flexible Instance, false otherwise
+     */
+    public static function onAppEngineFlexible()
+    {
+        return substr(getenv('GAE_INSTANCE'), 0, 4) === 'aef-';
+    }
+
+    /**
+     * Determines if this a GCE instance, by accessing the expected metadata
+     * host.
+     * If $httpHandler is not specified a the default HttpHandler is used.
+     *
+     * @param callable $httpHandler callback which delivers psr7 request
+     *
+     * @return true if this a GCEInstance false otherwise
+     */
+    public static function onGce(callable $httpHandler = null)
+    {
+        $httpHandler = $httpHandler
+            ?: HttpHandlerFactory::build(HttpClientCache::getHttpClient());
+
+        $checkUri = 'http://' . self::METADATA_IP;
+        for ($i = 1; $i <= self::MAX_COMPUTE_PING_TRIES; $i++) {
+            try {
+                // Comment from: oauth2client/client.py
+                //
+                // Note: the explicit `timeout` below is a workaround. The underlying
+                // issue is that resolving an unknown host on some networks will take
+                // 20-30 seconds; making this timeout short fixes the issue, but
+                // could lead to false negatives in the event that we are on GCE, but
+                // the metadata resolution was particularly slow. The latter case is
+                // "unlikely".
+                $resp = $httpHandler(
+                    new Request(
+                        'GET',
+                        $checkUri,
+                        [self::FLAVOR_HEADER => 'Google']
+                    ),
+                    ['timeout' => self::COMPUTE_PING_CONNECTION_TIMEOUT_S]
+                );
+
+                return $resp->getHeaderLine(self::FLAVOR_HEADER) == 'Google';
+            } catch (ClientException $e) {
+            } catch (ServerException $e) {
+            } catch (RequestException $e) {
+            }
+        }
+        return false;
+    }
+
+    /**
+     * Implements FetchAuthTokenInterface#fetchAuthToken.
+     *
+     * Fetches the auth tokens from the GCE metadata host if it is available.
+     * If $httpHandler is not specified a the default HttpHandler is used.
+     *
+     * @param callable $httpHandler callback which delivers psr7 request
+     *
+     * @return array A set of auth related metadata, containing the following
+     * keys:
+     *   - access_token (string)
+     *   - expires_in (int)
+     *   - token_type (string)
+     *
+     * @throws \Exception
+     */
+    public function fetchAuthToken(callable $httpHandler = null)
+    {
+        $httpHandler = $httpHandler
+            ?: HttpHandlerFactory::build(HttpClientCache::getHttpClient());
+
+        if (!$this->hasCheckedOnGce) {
+            $this->isOnGce = self::onGce($httpHandler);
+            $this->hasCheckedOnGce = true;
+        }
+        if (!$this->isOnGce) {
+            return array();  // return an empty array with no access token
+        }
+
+        $json = $this->getFromMetadata($httpHandler, self::getTokenUri());
+        if (null === $json = json_decode($json, true)) {
+            throw new \Exception('Invalid JSON response');
+        }
+
+        // store this so we can retrieve it later
+        $this->lastReceivedToken = $json;
+        $this->lastReceivedToken['expires_at'] = time() + $json['expires_in'];
+
+        return $json;
+    }
+
+    /**
+     * @return string
+     */
+    public function getCacheKey()
+    {
+        return self::cacheKey;
+    }
+
+    /**
+     * @return array|null
+     */
+    public function getLastReceivedToken()
+    {
+        if ($this->lastReceivedToken) {
+            return [
+                'access_token' => $this->lastReceivedToken['access_token'],
+                'expires_at' => $this->lastReceivedToken['expires_at'],
+            ];
+        }
+
+        return null;
+    }
+
+    /**
+     * Get the client name from GCE metadata.
+     *
+     * Subsequent calls will return a cached value.
+     *
+     * @param callable $httpHandler callback which delivers psr7 request
+     * @return string
+     */
+    public function getClientName(callable $httpHandler = null)
+    {
+        if ($this->clientName) {
+            return $this->clientName;
+        }
+
+        $httpHandler = $httpHandler
+            ?: HttpHandlerFactory::build(HttpClientCache::getHttpClient());
+
+        if (!$this->hasCheckedOnGce) {
+            $this->isOnGce = self::onGce($httpHandler);
+            $this->hasCheckedOnGce = true;
+        }
+
+        if (!$this->isOnGce) {
+            return '';
+        }
+
+        $this->clientName = $this->getFromMetadata($httpHandler, self::getClientNameUri());
+
+        return $this->clientName;
+    }
+
+    /**
+     * Sign a string using the default service account private key.
+     *
+     * This implementation uses IAM's signBlob API.
+     *
+     * @see https://cloud.google.com/iam/credentials/reference/rest/v1/projects.serviceAccounts/signBlob SignBlob
+     *
+     * @param string $stringToSign The string to sign.
+     * @param bool $forceOpenSsl [optional] Does not apply to this credentials
+     *        type.
+     * @return string
+     */
+    public function signBlob($stringToSign, $forceOpenSsl = false)
+    {
+        $httpHandler = HttpHandlerFactory::build(HttpClientCache::getHttpClient());
+
+        // Providing a signer is useful for testing, but it's undocumented
+        // because it's not something a user would generally need to do.
+        $signer = $this->iam ?: new Iam($httpHandler);
+
+        $email = $this->getClientName($httpHandler);
+
+        $previousToken = $this->getLastReceivedToken();
+        $accessToken = $previousToken
+            ? $previousToken['access_token']
+            : $this->fetchAuthToken($httpHandler)['access_token'];
+
+        return $signer->signBlob($email, $accessToken, $stringToSign);
+    }
+
+    /**
+     * Fetch the value of a GCE metadata server URI.
+     *
+     * @param callable $httpHandler An HTTP Handler to deliver PSR7 requests.
+     * @param string $uri The metadata URI.
+     * @return string
+     */
+    private function getFromMetadata(callable $httpHandler, $uri)
+    {
+        $resp = $httpHandler(
+            new Request(
+                'GET',
+                $uri,
+                [self::FLAVOR_HEADER => 'Google']
+            )
+        );
+
+        return (string) $resp->getBody();
+    }
+}

vendor/google/auth/src/Credentials/IAMCredentials.php

@@ -0,0 +1,89 @@
+<?php
+/*
+ * Copyright 2015 Google Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License 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 Google\Auth\Credentials;
+
+/**
+ * Authenticates requests using IAM credentials.
+ */
+class IAMCredentials
+{
+    const SELECTOR_KEY = 'x-goog-iam-authority-selector';
+    const TOKEN_KEY = 'x-goog-iam-authorization-token';
+
+    /**
+     * @var string
+     */
+    private $selector;
+
+    /**
+     * @var string
+     */
+    private $token;
+
+    /**
+     * @param $selector string the IAM selector
+     * @param $token string the IAM token
+     */
+    public function __construct($selector, $token)
+    {
+        if (!is_string($selector)) {
+            throw new \InvalidArgumentException(
+                'selector must be a string');
+        }
+        if (!is_string($token)) {
+            throw new \InvalidArgumentException(
+                'token must be a string');
+        }
+
+        $this->selector = $selector;
+        $this->token = $token;
+    }
+
+    /**
+     * export a callback function which updates runtime metadata.
+     *
+     * @return array updateMetadata function
+     */
+    public function getUpdateMetadataFunc()
+    {
+        return array($this, 'updateMetadata');
+    }
+
+    /**
+     * Updates metadata with the appropriate header metadata.
+     *
+     * @param array $metadata metadata hashmap
+     * @param string $unusedAuthUri optional auth uri
+     * @param callable $httpHandler callback which delivers psr7 request
+     *        Note: this param is unused here, only included here for
+     *        consistency with other credentials class
+     *
+     * @return array updated metadata hashmap
+     */
+    public function updateMetadata(
+        $metadata,
+        $unusedAuthUri = null,
+        callable $httpHandler = null
+    ) {
+        $metadata_copy = $metadata;
+        $metadata_copy[self::SELECTOR_KEY] = $this->selector;
+        $metadata_copy[self::TOKEN_KEY] = $this->token;
+
+        return $metadata_copy;
+    }
+}

vendor/google/auth/src/Credentials/InsecureCredentials.php

@@ -0,0 +1,70 @@
+<?php
+/*
+ * Copyright 2018 Google Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License 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 Google\Auth\Credentials;
+
+use Google\Auth\FetchAuthTokenInterface;
+
+/**
+ * Provides a set of credentials that will always return an empty access token.
+ * This is useful for APIs which do not require authentication, for local
+ * service emulators, and for testing.
+ */
+class InsecureCredentials implements FetchAuthTokenInterface
+{
+    /**
+     * @var array
+     */
+    private $token = [
+        'access_token' => ''
+    ];
+
+    /**
+     * Fetches the auth token. In this case it returns an empty string.
+     *
+     * @param callable $httpHandler
+     * @return array A set of auth related metadata, containing the following
+     * keys:
+     *   - access_token (string)
+     */
+    public function fetchAuthToken(callable $httpHandler = null)
+    {
+        return $this->token;
+    }
+
+    /**
+     * Returns the cache key. In this case it returns a null value, disabling
+     * caching.
+     *
+     * @return string|null
+     */
+    public function getCacheKey()
+    {
+        return null;
+    }
+
+    /**
+     * Fetches the last received token. In this case, it returns the same empty string
+     * auth token.
+     *
+     * @return array
+     */
+    public function getLastReceivedToken()
+    {
+        return $this->token;
+    }
+}

vendor/google/auth/src/Credentials/ServiceAccountCredentials.php

@@ -0,0 +1,198 @@
+<?php
+/*
+ * Copyright 2015 Google Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License 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 Google\Auth\Credentials;
+
+use Google\Auth\CredentialsLoader;
+use Google\Auth\OAuth2;
+use Google\Auth\ServiceAccountSignerTrait;
+use Google\Auth\SignBlobInterface;
+
+/**
+ * ServiceAccountCredentials supports authorization using a Google service
+ * account.
+ *
+ * (cf https://developers.google.com/accounts/docs/OAuth2ServiceAccount)
+ *
+ * It's initialized using the json key file that's downloadable from developer
+ * console, which should contain a private_key and client_email fields that it
+ * uses.
+ *
+ * Use it with AuthTokenMiddleware to authorize http requests:
+ *
+ *   use Google\Auth\Credentials\ServiceAccountCredentials;
+ *   use Google\Auth\Middleware\AuthTokenMiddleware;
+ *   use GuzzleHttp\Client;
+ *   use GuzzleHttp\HandlerStack;
+ *
+ *   $sa = new ServiceAccountCredentials(
+ *       'https://www.googleapis.com/auth/taskqueue',
+ *       '/path/to/your/json/key_file.json'
+ *   );
+ *   $middleware = new AuthTokenMiddleware($sa);
+ *   $stack = HandlerStack::create();
+ *   $stack->push($middleware);
+ *
+ *   $client = new Client([
+ *       'handler' => $stack,
+ *       'base_uri' => 'https://www.googleapis.com/taskqueue/v1beta2/projects/',
+ *       'auth' => 'google_auth' // authorize all requests
+ *   ]);
+ *
+ *   $res = $client->get('myproject/taskqueues/myqueue');
+ */
+class ServiceAccountCredentials extends CredentialsLoader implements SignBlobInterface
+{
+    use ServiceAccountSignerTrait;
+
+    /**
+     * The OAuth2 instance used to conduct authorization.
+     *
+     * @var OAuth2
+     */
+    protected $auth;
+
+    /**
+     * Create a new ServiceAccountCredentials.
+     *
+     * @param string|array $scope the scope of the access request, expressed
+     *   either as an Array or as a space-delimited String.
+     * @param string|array $jsonKey JSON credential file path or JSON credentials
+     *   as an associative array
+     * @param string $sub an email address account to impersonate, in situations when
+     *   the service account has been delegated domain wide access.
+     */
+    public function __construct(
+        $scope,
+        $jsonKey,
+        $sub = null
+    ) {
+        if (is_string($jsonKey)) {
+            if (!file_exists($jsonKey)) {
+                throw new \InvalidArgumentException('file does not exist');
+            }
+            $jsonKeyStream = file_get_contents($jsonKey);
+            if (!$jsonKey = json_decode($jsonKeyStream, true)) {
+                throw new \LogicException('invalid json for auth config');
+            }
+        }
+        if (!array_key_exists('client_email', $jsonKey)) {
+            throw new \InvalidArgumentException(
+                'json key is missing the client_email field');
+        }
+        if (!array_key_exists('private_key', $jsonKey)) {
+            throw new \InvalidArgumentException(
+                'json key is missing the private_key field');
+        }
+        $this->auth = new OAuth2([
+            'audience' => self::TOKEN_CREDENTIAL_URI,
+            'issuer' => $jsonKey['client_email'],
+            'scope' => $scope,
+            'signingAlgorithm' => 'RS256',
+            'signingKey' => $jsonKey['private_key'],
+            'sub' => $sub,
+            'tokenCredentialUri' => self::TOKEN_CREDENTIAL_URI,
+        ]);
+    }
+
+    /**
+     * @param callable $httpHandler
+     *
+     * @return array A set of auth related metadata, containing the following
+     * keys:
+     *   - access_token (string)
+     *   - expires_in (int)
+     *   - token_type (string)
+     */
+    public function fetchAuthToken(callable $httpHandler = null)
+    {
+        return $this->auth->fetchAuthToken($httpHandler);
+    }
+
+    /**
+     * @return string
+     */
+    public function getCacheKey()
+    {
+        $key = $this->auth->getIssuer() . ':' . $this->auth->getCacheKey();
+        if ($sub = $this->auth->getSub()) {
+            $key .= ':' . $sub;
+        }
+
+        return $key;
+    }
+
+    /**
+     * @return array
+     */
+    public function getLastReceivedToken()
+    {
+        return $this->auth->getLastReceivedToken();
+    }
+
+    /**
+     * Updates metadata with the authorization token.
+     *
+     * @param array $metadata metadata hashmap
+     * @param string $authUri optional auth uri
+     * @param callable $httpHandler callback which delivers psr7 request
+     *
+     * @return array updated metadata hashmap
+     */
+    public function updateMetadata(
+        $metadata,
+        $authUri = null,
+        callable $httpHandler = null
+    ) {
+        // scope exists. use oauth implementation
+        $scope = $this->auth->getScope();
+        if (!is_null($scope)) {
+            return parent::updateMetadata($metadata, $authUri, $httpHandler);
+        }
+
+        // no scope found. create jwt with the auth uri
+        $credJson = array(
+            'private_key' => $this->auth->getSigningKey(),
+            'client_email' => $this->auth->getIssuer(),
+        );
+        $jwtCreds = new ServiceAccountJwtAccessCredentials($credJson);
+
+        return $jwtCreds->updateMetadata($metadata, $authUri, $httpHandler);
+    }
+
+    /**
+     * @param string $sub an email address account to impersonate, in situations when
+     *   the service account has been delegated domain wide access.
+     */
+    public function setSub($sub)
+    {
+        $this->auth->setSub($sub);
+    }
+
+    /**
+     * Get the client name from the keyfile.
+     *
+     * In this case, it returns the keyfile's client_email key.
+     *
+     * @param callable $httpHandler Not used by this credentials type.
+     * @return string
+     */
+    public function getClientName(callable $httpHandler = null)
+    {
+        return $this->auth->getIssuer();
+    }
+}

vendor/google/auth/src/Credentials/ServiceAccountJwtAccessCredentials.php

@@ -0,0 +1,150 @@
+<?php
+/*
+ * Copyright 2015 Google Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License 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 Google\Auth\Credentials;
+
+use Google\Auth\CredentialsLoader;
+use Google\Auth\OAuth2;
+use Google\Auth\ServiceAccountSignerTrait;
+use Google\Auth\SignBlobInterface;
+
+/**
+ * Authenticates requests using Google's Service Account credentials via
+ * JWT Access.
+ *
+ * This class allows authorizing requests for service accounts directly
+ * from credentials from a json key file downloaded from the developer
+ * console (via 'Generate new Json Key').  It is not part of any OAuth2
+ * flow, rather it creates a JWT and sends that as a credential.
+ */
+class ServiceAccountJwtAccessCredentials extends CredentialsLoader implements SignBlobInterface
+{
+    use ServiceAccountSignerTrait;
+
+    /**
+     * The OAuth2 instance used to conduct authorization.
+     *
+     * @var OAuth2
+     */
+    protected $auth;
+
+    /**
+     * Create a new ServiceAccountJwtAccessCredentials.
+     *
+     * @param string|array $jsonKey JSON credential file path or JSON credentials
+     *   as an associative array
+     */
+    public function __construct($jsonKey)
+    {
+        if (is_string($jsonKey)) {
+            if (!file_exists($jsonKey)) {
+                throw new \InvalidArgumentException('file does not exist');
+            }
+            $jsonKeyStream = file_get_contents($jsonKey);
+            if (!$jsonKey = json_decode($jsonKeyStream, true)) {
+                throw new \LogicException('invalid json for auth config');
+            }
+        }
+        if (!array_key_exists('client_email', $jsonKey)) {
+            throw new \InvalidArgumentException(
+                'json key is missing the client_email field');
+        }
+        if (!array_key_exists('private_key', $jsonKey)) {
+            throw new \InvalidArgumentException(
+                'json key is missing the private_key field');
+        }
+        $this->auth = new OAuth2([
+            'issuer' => $jsonKey['client_email'],
+            'sub' => $jsonKey['client_email'],
+            'signingAlgorithm' => 'RS256',
+            'signingKey' => $jsonKey['private_key'],
+        ]);
+    }
+
+    /**
+     * Updates metadata with the authorization token.
+     *
+     * @param array $metadata metadata hashmap
+     * @param string $authUri optional auth uri
+     * @param callable $httpHandler callback which delivers psr7 request
+     *
+     * @return array updated metadata hashmap
+     */
+    public function updateMetadata(
+        $metadata,
+        $authUri = null,
+        callable $httpHandler = null
+    ) {
+        if (empty($authUri)) {
+            return $metadata;
+        }
+
+        $this->auth->setAudience($authUri);
+
+        return parent::updateMetadata($metadata, $authUri, $httpHandler);
+    }
+
+    /**
+     * Implements FetchAuthTokenInterface#fetchAuthToken.
+     *
+     * @param callable $httpHandler
+     *
+     * @return array|void A set of auth related metadata, containing the
+     * following keys:
+     *   - access_token (string)
+     */
+    public function fetchAuthToken(callable $httpHandler = null)
+    {
+        $audience = $this->auth->getAudience();
+        if (empty($audience)) {
+            return null;
+        }
+
+        $access_token = $this->auth->toJwt();
+
+        return array('access_token' => $access_token);
+    }
+
+    /**
+     * @return string
+     */
+    public function getCacheKey()
+    {
+        return $this->auth->getCacheKey();
+    }
+
+    /**
+     * @return array
+     */
+    public function getLastReceivedToken()
+    {
+        return $this->auth->getLastReceivedToken();
+    }
+
+    /**
+     * Get the client name from the keyfile.
+     *
+     * In this case, it returns the keyfile's client_email key.
+     *
+     * @param callable $httpHandler Not used by this credentials type.
+     * @return string
+     */
+    public function getClientName(callable $httpHandler = null)
+    {
+        return $this->auth->getIssuer();
+    }
+}

vendor/google/auth/src/Credentials/UserRefreshCredentials.php

@@ -0,0 +1,137 @@
+<?php
+/*
+ * Copyright 2015 Google Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License 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 Google\Auth\Credentials;
+
+use Google\Auth\CredentialsLoader;
+use Google\Auth\OAuth2;
+
+/**
+ * Authenticates requests using User Refresh credentials.
+ *
+ * This class allows authorizing requests from user refresh tokens.
+ *
+ * This the end of the result of a 3LO flow.  E.g, the end result of
+ * 'gcloud auth login' saves a file with these contents in well known
+ * location
+ *
+ * @see [Application Default Credentials](http://goo.gl/mkAHpZ)
+ */
+class UserRefreshCredentials extends CredentialsLoader
+{
+    const CLOUD_SDK_CLIENT_ID =
+        '764086051850-6qr4p6gpi6hn506pt8ejuq83di341hur.apps.googleusercontent.com';
+
+    const SUPPRESS_CLOUD_SDK_CREDS_WARNING_ENV = 'SUPPRESS_GCLOUD_CREDS_WARNING';
+
+    /**
+     * The OAuth2 instance used to conduct authorization.
+     *
+     * @var OAuth2
+     */
+    protected $auth;
+
+    /**
+     * Create a new UserRefreshCredentials.
+     *
+     * @param string|array $scope the scope of the access request, expressed
+     *   either as an Array or as a space-delimited String.
+     * @param string|array $jsonKey JSON credential file path or JSON credentials
+     *   as an associative array
+     */
+    public function __construct(
+        $scope,
+        $jsonKey
+    ) {
+        if (is_string($jsonKey)) {
+            if (!file_exists($jsonKey)) {
+                throw new \InvalidArgumentException('file does not exist');
+            }
+            $jsonKeyStream = file_get_contents($jsonKey);
+            if (!$jsonKey = json_decode($jsonKeyStream, true)) {
+                throw new \LogicException('invalid json for auth config');
+            }
+        }
+        if (!array_key_exists('client_id', $jsonKey)) {
+            throw new \InvalidArgumentException(
+                'json key is missing the client_id field');
+        }
+        if (!array_key_exists('client_secret', $jsonKey)) {
+            throw new \InvalidArgumentException(
+                'json key is missing the client_secret field');
+        }
+        if (!array_key_exists('refresh_token', $jsonKey)) {
+            throw new \InvalidArgumentException(
+                'json key is missing the refresh_token field');
+        }
+        $this->auth = new OAuth2([
+            'clientId' => $jsonKey['client_id'],
+            'clientSecret' => $jsonKey['client_secret'],
+            'refresh_token' => $jsonKey['refresh_token'],
+            'scope' => $scope,
+            'tokenCredentialUri' => self::TOKEN_CREDENTIAL_URI,
+        ]);
+        if ($jsonKey['client_id'] === self::CLOUD_SDK_CLIENT_ID
+            && getenv(self::SUPPRESS_CLOUD_SDK_CREDS_WARNING_ENV) !== 'true') {
+            trigger_error(
+                'Your application has authenticated using end user credentials '
+                . 'from Google Cloud SDK. We recommend that most server '
+                . 'applications use service accounts instead. If your '
+                . 'application continues to use end user credentials '
+                . 'from Cloud SDK, you might receive a "quota exceeded" '
+                . 'or "API not enabled" error. For more information about '
+                . 'service accounts, see '
+                . 'https://cloud.google.com/docs/authentication/. '
+                . 'To disable this warning, set '
+                . self::SUPPRESS_CLOUD_SDK_CREDS_WARNING_ENV
+                . ' environment variable to "true".',
+                E_USER_WARNING);
+        }
+    }
+
+    /**
+     * @param callable $httpHandler
+     *
+     * @return array A set of auth related metadata, containing the following
+     * keys:
+     *   - access_token (string)
+     *   - expires_in (int)
+     *   - scope (string)
+     *   - token_type (string)
+     *   - id_token (string)
+     */
+    public function fetchAuthToken(callable $httpHandler = null)
+    {
+        return $this->auth->fetchAuthToken($httpHandler);
+    }
+
+    /**
+     * @return string
+     */
+    public function getCacheKey()
+    {
+        return $this->auth->getClientId() . ':' . $this->auth->getCacheKey();
+    }
+
+    /**
+     * @return array
+     */
+    public function getLastReceivedToken()
+    {
+        return $this->auth->getLastReceivedToken();
+    }
+}

vendor/google/auth/src/CredentialsLoader.php

@@ -0,0 +1,223 @@
+<?php
+/*
+ * Copyright 2015 Google Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License 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 Google\Auth;
+
+use Google\Auth\Credentials\InsecureCredentials;
+use Google\Auth\Credentials\ServiceAccountCredentials;
+use Google\Auth\Credentials\UserRefreshCredentials;
+
+/**
+ * CredentialsLoader contains the behaviour used to locate and find default
+ * credentials files on the file system.
+ */
+abstract class CredentialsLoader implements FetchAuthTokenInterface
+{
+    const TOKEN_CREDENTIAL_URI = 'https://oauth2.googleapis.com/token';
+    const ENV_VAR = 'GOOGLE_APPLICATION_CREDENTIALS';
+    const WELL_KNOWN_PATH = 'gcloud/application_default_credentials.json';
+    const NON_WINDOWS_WELL_KNOWN_PATH_BASE = '.config';
+    const AUTH_METADATA_KEY = 'authorization';
+
+    /**
+     * @param string $cause
+     * @return string
+     */
+    private static function unableToReadEnv($cause)
+    {
+        $msg = 'Unable to read the credential file specified by ';
+        $msg .= ' GOOGLE_APPLICATION_CREDENTIALS: ';
+        $msg .= $cause;
+
+        return $msg;
+    }
+
+    /**
+     * @return bool
+     */
+    private static function isOnWindows()
+    {
+        return strtoupper(substr(PHP_OS, 0, 3)) === 'WIN';
+    }
+
+    /**
+     * Load a JSON key from the path specified in the environment.
+     *
+     * Load a JSON key from the path specified in the environment
+     * variable GOOGLE_APPLICATION_CREDENTIALS. Return null if
+     * GOOGLE_APPLICATION_CREDENTIALS is not specified.
+     *
+     * @return array JSON key | null
+     */
+    public static function fromEnv()
+    {
+        $path = getenv(self::ENV_VAR);
+        if (empty($path)) {
+            return;
+        }
+        if (!file_exists($path)) {
+            $cause = 'file ' . $path . ' does not exist';
+            throw new \DomainException(self::unableToReadEnv($cause));
+        }
+        $jsonKey = file_get_contents($path);
+        return json_decode($jsonKey, true);
+    }
+
+    /**
+     * Load a JSON key from a well known path.
+     *
+     * The well known path is OS dependent:
+     * - windows: %APPDATA%/gcloud/application_default_credentials.json
+     * - others: $HOME/.config/gcloud/application_default_credentials.json
+     *
+     * If the file does not exists, this returns null.
+     *
+     * @return array JSON key | null
+     */
+    public static function fromWellKnownFile()
+    {
+        $rootEnv = self::isOnWindows() ? 'APPDATA' : 'HOME';
+        $path = [getenv($rootEnv)];
+        if (!self::isOnWindows()) {
+            $path[] = self::NON_WINDOWS_WELL_KNOWN_PATH_BASE;
+        }
+        $path[] = self::WELL_KNOWN_PATH;
+        $path = implode(DIRECTORY_SEPARATOR, $path);
+        if (!file_exists($path)) {
+            return;
+        }
+        $jsonKey = file_get_contents($path);
+        return json_decode($jsonKey, true);
+    }
+
+    /**
+     * Create a new Credentials instance.
+     *
+     * @param string|array $scope the scope of the access request, expressed
+     *   either as an Array or as a space-delimited String.
+     * @param array $jsonKey the JSON credentials.
+     *
+     * @return ServiceAccountCredentials|UserRefreshCredentials
+     */
+    public static function makeCredentials($scope, array $jsonKey)
+    {
+        if (!array_key_exists('type', $jsonKey)) {
+            throw new \InvalidArgumentException('json key is missing the type field');
+        }
+
+        if ($jsonKey['type'] == 'service_account') {
+            return new ServiceAccountCredentials($scope, $jsonKey);
+        }
+
+        if ($jsonKey['type'] == 'authorized_user') {
+            return new UserRefreshCredentials($scope, $jsonKey);
+        }
+
+        throw new \InvalidArgumentException('invalid value in the type field');
+    }
+
+    /**
+     * Create an authorized HTTP Client from an instance of FetchAuthTokenInterface.
+     *
+     * @param FetchAuthTokenInterface $fetcher is used to fetch the auth token
+     * @param array $httpClientOptoins (optional) Array of request options to apply.
+     * @param callable $httpHandler (optional) http client to fetch the token.
+     * @param callable $tokenCallback (optional) function to be called when a new token is fetched.
+     *
+     * @return \GuzzleHttp\Client
+     */
+    public static function makeHttpClient(
+        FetchAuthTokenInterface $fetcher,
+        array $httpClientOptions = [],
+        callable $httpHandler = null,
+        callable $tokenCallback = null
+    ) {
+        $version = \GuzzleHttp\ClientInterface::VERSION;
+
+        switch ($version[0]) {
+            case '5':
+                $client = new \GuzzleHttp\Client($httpClientOptions);
+                $client->setDefaultOption('auth', 'google_auth');
+                $subscriber = new Subscriber\AuthTokenSubscriber(
+                    $fetcher,
+                    $httpHandler,
+                    $tokenCallback
+                );
+                $client->getEmitter()->attach($subscriber);
+                return $client;
+            case '6':
+                $middleware = new Middleware\AuthTokenMiddleware(
+                    $fetcher,
+                    $httpHandler,
+                    $tokenCallback
+                );
+                $stack = \GuzzleHttp\HandlerStack::create();
+                $stack->push($middleware);
+
+                return new \GuzzleHttp\Client([
+                   'handler' => $stack,
+                   'auth' => 'google_auth',
+                ] + $httpClientOptions);
+            default:
+                throw new \Exception('Version not supported');
+        }
+    }
+
+    /**
+     * Create a new instance of InsecureCredentials.
+     *
+     * @return InsecureCredentials
+     */
+    public static function makeInsecureCredentials()
+    {
+        return new InsecureCredentials();
+    }
+
+    /**
+     * export a callback function which updates runtime metadata.
+     *
+     * @return array updateMetadata function
+     */
+    public function getUpdateMetadataFunc()
+    {
+        return array($this, 'updateMetadata');
+    }
+
+    /**
+     * Updates metadata with the authorization token.
+     *
+     * @param array $metadata metadata hashmap
+     * @param string $authUri optional auth uri
+     * @param callable $httpHandler callback which delivers psr7 request
+     *
+     * @return array updated metadata hashmap
+     */
+    public function updateMetadata(
+        $metadata,
+        $authUri = null,
+        callable $httpHandler = null
+    ) {
+        $result = $this->fetchAuthToken($httpHandler);
+        if (!isset($result['access_token'])) {
+            return $metadata;
+        }
+        $metadata_copy = $metadata;
+        $metadata_copy[self::AUTH_METADATA_KEY] = array('Bearer ' . $result['access_token']);
+
+        return $metadata_copy;
+    }
+}

vendor/google/auth/src/FetchAuthTokenCache.php

@@ -0,0 +1,142 @@
+<?php
+/*
+ * Copyright 2010 Google Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License 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 Google\Auth;
+
+use Psr\Cache\CacheItemPoolInterface;
+
+/**
+ * A class to implement caching for any object implementing
+ * FetchAuthTokenInterface
+ */
+class FetchAuthTokenCache implements FetchAuthTokenInterface, SignBlobInterface
+{
+    use CacheTrait;
+
+    /**
+     * @var FetchAuthTokenInterface
+     */
+    private $fetcher;
+
+    /**
+     * @var array
+     */
+    private $cacheConfig;
+
+    /**
+     * @var CacheItemPoolInterface
+     */
+    private $cache;
+
+    public function __construct(
+        FetchAuthTokenInterface $fetcher,
+        array $cacheConfig = null,
+        CacheItemPoolInterface $cache
+    ) {
+        $this->fetcher = $fetcher;
+        $this->cache = $cache;
+        $this->cacheConfig = array_merge([
+            'lifetime' => 1500,
+            'prefix' => '',
+        ], (array) $cacheConfig);
+    }
+
+    /**
+     * Implements FetchAuthTokenInterface#fetchAuthToken.
+     *
+     * Checks the cache for a valid auth token and fetches the auth tokens
+     * from the supplied fetcher.
+     *
+     * @param callable $httpHandler callback which delivers psr7 request
+     *
+     * @return array the response
+     *
+     * @throws \Exception
+     */
+    public function fetchAuthToken(callable $httpHandler = null)
+    {
+        // Use the cached value if its available.
+        //
+        // TODO: correct caching; update the call to setCachedValue to set the expiry
+        // to the value returned with the auth token.
+        //
+        // TODO: correct caching; enable the cache to be cleared.
+        $cacheKey = $this->fetcher->getCacheKey();
+        $cached = $this->getCachedValue($cacheKey);
+        if (!empty($cached)) {
+            return ['access_token' => $cached];
+        }
+
+        $auth_token = $this->fetcher->fetchAuthToken($httpHandler);
+
+        if (isset($auth_token['access_token'])) {
+            $this->setCachedValue($cacheKey, $auth_token['access_token']);
+        }
+
+        return $auth_token;
+    }
+
+    /**
+     * @return string
+     */
+    public function getCacheKey()
+    {
+        return $this->getFullCacheKey($this->fetcher->getCacheKey());
+    }
+
+    /**
+     * @return array|null
+     */
+    public function getLastReceivedToken()
+    {
+        return $this->fetcher->getLastReceivedToken();
+    }
+
+    /**
+     * Get the client name from the fetcher.
+     *
+     * @param callable $httpHandler An HTTP handler to deliver PSR7 requests.
+     * @return string
+     */
+    public function getClientName(callable $httpHandler = null)
+    {
+        return $this->fetcher->getClientName($httpHandler);
+    }
+
+    /**
+     * Sign a blob using the fetcher.
+     *
+     * @param string $stringToSign The string to sign.
+     * @param bool $forceOpenssl Require use of OpenSSL for local signing. Does
+     *        not apply to signing done using external services. **Defaults to**
+     *        `false`.
+     * @return string The resulting signature.
+     * @throws \RuntimeException If the fetcher does not implement
+     *     `Google\Auth\SignBlobInterface`.
+     */
+    public function signBlob($stringToSign, $forceOpenSsl =  false)
+    {
+        if (!$this->fetcher instanceof SignBlobInterface) {
+            throw new \RuntimeException(
+                'Credentials fetcher does not implement ' .
+                'Google\Auth\SignBlobInterface'
+            );
+        }
+
+        return $this->fetcher->signBlob($stringToSign, $forceOpenSsl);
+    }
+}

vendor/google/auth/src/FetchAuthTokenInterface.php

@@ -0,0 +1,55 @@
+<?php
+/*
+ * Copyright 2015 Google Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License 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 Google\Auth;
+
+/**
+ * An interface implemented by objects that can fetch auth tokens.
+ */
+interface FetchAuthTokenInterface
+{
+    /**
+     * Fetches the auth tokens based on the current state.
+     *
+     * @param callable $httpHandler callback which delivers psr7 request
+     *
+     * @return array a hash of auth tokens
+     */
+    public function fetchAuthToken(callable $httpHandler = null);
+
+    /**
+     * Obtains a key that can used to cache the results of #fetchAuthToken.
+     *
+     * If the value is empty, the auth token is not cached.
+     *
+     * @return string a key that may be used to cache the auth token.
+     */
+    public function getCacheKey();
+
+    /**
+     * Returns an associative array with the token and
+     * expiration time.
+     *
+     * @return null|array {
+     *      The last received access token.
+     *
+     * @var string $access_token The access token string.
+     * @var int $expires_at The time the token expires as a UNIX timestamp.
+     * }
+     */
+    public function getLastReceivedToken();
+}

vendor/google/auth/src/HttpHandler/Guzzle5HttpHandler.php

@@ -0,0 +1,128 @@
+<?php
+/**
+ * Copyright 2015 Google Inc. 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.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License 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 Google\Auth\HttpHandler;
+
+use Exception;
+use GuzzleHttp\ClientInterface;
+use GuzzleHttp\Message\ResponseInterface as Guzzle5ResponseInterface;
+use GuzzleHttp\Promise\Promise;
+use GuzzleHttp\Promise\RejectedPromise;
+use GuzzleHttp\Psr7\Response;
+use Psr\Http\Message\RequestInterface;
+use Psr\Http\Message\ResponseInterface;
+
+class Guzzle5HttpHandler
+{
+    /**
+     * @var ClientInterface
+     */
+    private $client;
+
+    /**
+     * @param ClientInterface $client
+     */
+    public function __construct(ClientInterface $client)
+    {
+        $this->client = $client;
+    }
+
+    /**
+     * Accepts a PSR-7 Request and an array of options and returns a PSR-7 response.
+     *
+     * @param RequestInterface $request
+     * @param array $options
+     *
+     * @return ResponseInterface
+     */
+    public function __invoke(RequestInterface $request, array $options = [])
+    {
+        $response = $this->client->send(
+            $this->createGuzzle5Request($request, $options)
+        );
+
+        return $this->createPsr7Response($response);
+    }
+
+    /**
+     * Accepts a PSR-7 request and an array of options and returns a PromiseInterface
+     *
+     * @param RequestInterface $request
+     * @param array $options
+     *
+     * @return Promise
+     */
+    public function async(RequestInterface $request, array $options = [])
+    {
+        if (!class_exists('GuzzleHttp\Promise\Promise')) {
+            throw new Exception('Install guzzlehttp/promises to use async with Guzzle 5');
+        }
+
+        $futureResponse = $this->client->send(
+            $this->createGuzzle5Request(
+                $request,
+                ['future' => true] + $options
+            )
+        );
+
+        $promise = new Promise(
+            function () use ($futureResponse) {
+                try {
+                    $futureResponse->wait();
+                } catch (Exception $e) {
+                    // The promise is already delivered when the exception is
+                    // thrown, so don't rethrow it.
+                }
+            },
+            [$futureResponse, 'cancel']
+        );
+
+        $futureResponse->then([$promise, 'resolve'], [$promise, 'reject']);
+
+        return $promise->then(
+            function (Guzzle5ResponseInterface $response) {
+                // Adapt the Guzzle 5 Response to a PSR-7 Response.
+                return $this->createPsr7Response($response);
+            },
+            function (Exception $e) {
+                return new RejectedPromise($e);
+            }
+        );
+    }
+
+    private function createGuzzle5Request(RequestInterface $request, array $options)
+    {
+        return $this->client->createRequest(
+            $request->getMethod(),
+            $request->getUri(),
+            array_merge_recursive([
+                'headers' => $request->getHeaders(),
+                'body' => $request->getBody(),
+            ], $options)
+        );
+    }
+
+    private function createPsr7Response(Guzzle5ResponseInterface $response)
+    {
+        return new Response(
+            $response->getStatusCode(),
+            $response->getHeaders() ?: [],
+            $response->getBody(),
+            $response->getProtocolVersion(),
+            $response->getReasonPhrase()
+        );
+    }
+}

vendor/google/auth/src/HttpHandler/Guzzle6HttpHandler.php

@@ -0,0 +1,49 @@
+<?php
+
+namespace Google\Auth\HttpHandler;
+
+use GuzzleHttp\ClientInterface;
+use Psr\Http\Message\RequestInterface;
+use Psr\Http\Message\ResponseInterface;
+
+class Guzzle6HttpHandler
+{
+    /**
+     * @var ClientInterface
+     */
+    private $client;
+
+    /**
+     * @param ClientInterface $client
+     */
+    public function __construct(ClientInterface $client)
+    {
+        $this->client = $client;
+    }
+
+    /**
+     * Accepts a PSR-7 request and an array of options and returns a PSR-7 response.
+     *
+     * @param RequestInterface $request
+     * @param array $options
+     *
+     * @return ResponseInterface
+     */
+    public function __invoke(RequestInterface $request, array $options = [])
+    {
+        return $this->client->send($request, $options);
+    }
+
+    /**
+     * Accepts a PSR-7 request and an array of options and returns a PromiseInterface
+     *
+     * @param RequestInterface $request
+     * @param array $options
+     *
+     * @return \GuzzleHttp\Promise\Promise
+     */
+    public function async(RequestInterface $request, array $options = [])
+    {
+        return $this->client->sendAsync($request, $options);
+    }
+}

vendor/google/auth/src/HttpHandler/HttpClientCache.php

@@ -0,0 +1,54 @@
+<?php
+/*
+ * Copyright 2019 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License 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 Google\Auth\HttpHandler;
+
+use GuzzleHttp\ClientInterface;
+
+/**
+ * Stores an HTTP Client in order to prevent multiple instantiations.
+ */
+class HttpClientCache
+{
+    /**
+     * @var ClientInterface|null
+     */
+    private static $httpClient;
+
+    /**
+     * Cache an HTTP Client for later calls.
+     *
+     * Passing null will unset the cached client.
+     *
+     * @param ClientInterface|null $client
+     * @return void
+     */
+    public static function setHttpClient(ClientInterface $client = null)
+    {
+        self::$httpClient = $client;
+    }
+
+    /**
+     * Get the stored HTTP Client, or null.
+     *
+     * @return ClientInterface|null
+     */
+    public static function getHttpClient()
+    {
+        return self::$httpClient;
+    }
+}

vendor/google/auth/src/HttpHandler/HttpHandlerFactory.php

@@ -0,0 +1,45 @@
+<?php
+/**
+ * Copyright 2015 Google Inc. 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.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License 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 Google\Auth\HttpHandler;
+
+use GuzzleHttp\Client;
+use GuzzleHttp\ClientInterface;
+
+class HttpHandlerFactory
+{
+    /**
+     * Builds out a default http handler for the installed version of guzzle.
+     *
+     * @param ClientInterface $client
+     * @return Guzzle5HttpHandler|Guzzle6HttpHandler
+     * @throws \Exception
+     */
+    public static function build(ClientInterface $client = null)
+    {
+        $version = ClientInterface::VERSION;
+        $client = $client ?: new Client();
+
+        switch ($version[0]) {
+            case '5':
+                return new Guzzle5HttpHandler($client);
+            case '6':
+                return new Guzzle6HttpHandler($client);
+            default:
+                throw new \Exception('Version not supported');
+        }
+    }
+}

vendor/google/auth/src/Iam.php

@@ -0,0 +1,99 @@
+<?php
+/*
+ * Copyright 2019 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License 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 Google\Auth;
+
+use Google\Auth\HttpHandler\HttpClientCache;
+use Google\Auth\HttpHandler\HttpHandlerFactory;
+use GuzzleHttp\Psr7;
+
+/**
+ * Tools for using the IAM API.
+ *
+ * @see https://cloud.google.com/iam/docs IAM Documentation
+ */
+class Iam
+{
+    const IAM_API_ROOT = 'https://iamcredentials.googleapis.com/v1';
+    const SIGN_BLOB_PATH = '%s:signBlob?alt=json';
+    const SERVICE_ACCOUNT_NAME = 'projects/-/serviceAccounts/%s';
+
+    /**
+     * @var callable
+     */
+    private $httpHandler;
+
+    /**
+     * @param callable $httpHandler [optional] The HTTP Handler to send requests.
+     */
+    public function __construct(callable $httpHandler = null)
+    {
+        $this->httpHandler = $httpHandler
+            ?: HttpHandlerFactory::build(HttpClientCache::getHttpClient());
+    }
+
+    /**
+     * Sign a string using the IAM signBlob API.
+     *
+     * Note that signing using IAM requires your service account to have the
+     * `iam.serviceAccounts.signBlob` permission, part of the "Service Account
+     * Token Creator" IAM role.
+     *
+     * @param string $email The service account email.
+     * @param string $accessToken An access token from the service account.
+     * @param string $stringToSign The string to be signed.
+     * @param array $delegates [optional] A list of service account emails to
+     *        add to the delegate chain. If omitted, the value of `$email` will
+     *        be used.
+     * @return string The signed string, base64-encoded.
+     */
+    public function signBlob($email, $accessToken, $stringToSign, array $delegates = [])
+    {
+        $httpHandler = $this->httpHandler;
+        $name = sprintf(self::SERVICE_ACCOUNT_NAME, $email);
+        $uri = self::IAM_API_ROOT . '/' . sprintf(self::SIGN_BLOB_PATH, $name);
+
+        if ($delegates) {
+            foreach ($delegates as &$delegate) {
+                $delegate = sprintf(self::SERVICE_ACCOUNT_NAME, $delegate);
+            }
+        } else {
+            $delegates = [$name];
+        }
+
+        $body = [
+            'delegates' => $delegates,
+            'payload' => base64_encode($stringToSign),
+        ];
+
+        $headers = [
+            'Authorization' => 'Bearer ' . $accessToken
+        ];
+
+        $request = new Psr7\Request(
+            'POST',
+            $uri,
+            $headers,
+            Psr7\stream_for(json_encode($body))
+        );
+
+        $res = $httpHandler($request);
+        $body = json_decode((string) $res->getBody(), true);
+
+        return $body['signedBlob'];
+    }
+}

vendor/google/auth/src/Middleware/AuthTokenMiddleware.php

@@ -0,0 +1,126 @@
+<?php
+/*
+ * Copyright 2015 Google Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License 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 Google\Auth\Middleware;
+
+use Google\Auth\FetchAuthTokenInterface;
+use Psr\Http\Message\RequestInterface;
+
+/**
+ * AuthTokenMiddleware is a Guzzle Middleware that adds an Authorization header
+ * provided by an object implementing FetchAuthTokenInterface.
+ *
+ * The FetchAuthTokenInterface#fetchAuthToken is used to obtain a hash; one of
+ * the values value in that hash is added as the authorization header.
+ *
+ * Requests will be accessed with the authorization header:
+ *
+ * 'authorization' 'Bearer <value of auth_token>'
+ */
+class AuthTokenMiddleware
+{
+    /**
+     * @var callback
+     */
+    private $httpHandler;
+
+    /**
+     * @var FetchAuthTokenInterface
+     */
+    private $fetcher;
+
+    /**
+     * @var callable
+     */
+    private $tokenCallback;
+
+    /**
+     * Creates a new AuthTokenMiddleware.
+     *
+     * @param FetchAuthTokenInterface $fetcher is used to fetch the auth token
+     * @param callable $httpHandler (optional) callback which delivers psr7 request
+     * @param callable $tokenCallback (optional) function to be called when a new token is fetched.
+     */
+    public function __construct(
+        FetchAuthTokenInterface $fetcher,
+        callable $httpHandler = null,
+        callable $tokenCallback = null
+    ) {
+        $this->fetcher = $fetcher;
+        $this->httpHandler = $httpHandler;
+        $this->tokenCallback = $tokenCallback;
+    }
+
+    /**
+     * Updates the request with an Authorization header when auth is 'google_auth'.
+     *
+     *   use Google\Auth\Middleware\AuthTokenMiddleware;
+     *   use Google\Auth\OAuth2;
+     *   use GuzzleHttp\Client;
+     *   use GuzzleHttp\HandlerStack;
+     *
+     *   $config = [..<oauth config param>.];
+     *   $oauth2 = new OAuth2($config)
+     *   $middleware = new AuthTokenMiddleware($oauth2);
+     *   $stack = HandlerStack::create();
+     *   $stack->push($middleware);
+     *
+     *   $client = new Client([
+     *       'handler' => $stack,
+     *       'base_uri' => 'https://www.googleapis.com/taskqueue/v1beta2/projects/',
+     *       'auth' => 'google_auth' // authorize all requests
+     *   ]);
+     *
+     *   $res = $client->get('myproject/taskqueues/myqueue');
+     *
+     * @param callable $handler
+     *
+     * @return \Closure
+     */
+    public function __invoke(callable $handler)
+    {
+        return function (RequestInterface $request, array $options) use ($handler) {
+            // Requests using "auth"="google_auth" will be authorized.
+            if (!isset($options['auth']) || $options['auth'] !== 'google_auth') {
+                return $handler($request, $options);
+            }
+
+            $request = $request->withHeader('authorization', 'Bearer ' . $this->fetchToken());
+
+            return $handler($request, $options);
+        };
+    }
+
+    /**
+     * Call fetcher to fetch the token.
+     *
+     * @return string
+     */
+    private function fetchToken()
+    {
+        $auth_tokens = $this->fetcher->fetchAuthToken($this->httpHandler);
+
+        if (array_key_exists('access_token', $auth_tokens)) {
+            // notify the callback if applicable
+            if ($this->tokenCallback) {
+                call_user_func($this->tokenCallback, $this->fetcher->getCacheKey(), $auth_tokens['access_token']);
+            }
+
+            return $auth_tokens['access_token'];
+        }
+    }
+}

vendor/google/auth/src/Middleware/ScopedAccessTokenMiddleware.php

@@ -0,0 +1,175 @@
+<?php
+/*
+ * Copyright 2015 Google Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License 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 Google\Auth\Middleware;
+
+use Google\Auth\CacheTrait;
+use Psr\Cache\CacheItemPoolInterface;
+use Psr\Http\Message\RequestInterface;
+
+/**
+ * ScopedAccessTokenMiddleware is a Guzzle Middleware that adds an Authorization
+ * header provided by a closure.
+ *
+ * The closure returns an access token, taking the scope, either a single
+ * string or an array of strings, as its value.  If provided, a cache will be
+ * used to preserve the access token for a given lifetime.
+ *
+ * Requests will be accessed with the authorization header:
+ *
+ * 'authorization' 'Bearer <value of auth_token>'
+ */
+class ScopedAccessTokenMiddleware
+{
+    use CacheTrait;
+
+    const DEFAULT_CACHE_LIFETIME = 1500;
+
+    /**
+     * @var CacheItemPoolInterface
+     */
+    private $cache;
+
+    /**
+     * @var array configuration
+     */
+    private $cacheConfig;
+
+    /**
+     * @var callable
+     */
+    private $tokenFunc;
+
+    /**
+     * @var array|string
+     */
+    private $scopes;
+
+    /**
+     * Creates a new ScopedAccessTokenMiddleware.
+     *
+     * @param callable $tokenFunc a token generator function
+     * @param array|string $scopes the token authentication scopes
+     * @param array $cacheConfig configuration for the cache when it's present
+     * @param CacheItemPoolInterface $cache an implementation of CacheItemPoolInterface
+     */
+    public function __construct(
+        callable $tokenFunc,
+        $scopes,
+        array $cacheConfig = null,
+        CacheItemPoolInterface $cache = null
+    ) {
+        $this->tokenFunc = $tokenFunc;
+        if (!(is_string($scopes) || is_array($scopes))) {
+            throw new \InvalidArgumentException(
+                'wants scope should be string or array');
+        }
+        $this->scopes = $scopes;
+
+        if (!is_null($cache)) {
+            $this->cache = $cache;
+            $this->cacheConfig = array_merge([
+                'lifetime' => self::DEFAULT_CACHE_LIFETIME,
+                'prefix' => '',
+            ], $cacheConfig);
+        }
+    }
+
+    /**
+     * Updates the request with an Authorization header when auth is 'scoped'.
+     *
+     *   E.g this could be used to authenticate using the AppEngine
+     *   AppIdentityService.
+     *
+     *   use google\appengine\api\app_identity\AppIdentityService;
+     *   use Google\Auth\Middleware\ScopedAccessTokenMiddleware;
+     *   use GuzzleHttp\Client;
+     *   use GuzzleHttp\HandlerStack;
+     *
+     *   $scope = 'https://www.googleapis.com/auth/taskqueue'
+     *   $middleware = new ScopedAccessTokenMiddleware(
+     *       'AppIdentityService::getAccessToken',
+     *       $scope,
+     *       [ 'prefix' => 'Google\Auth\ScopedAccessToken::' ],
+     *       $cache = new Memcache()
+     *   );
+     *   $stack = HandlerStack::create();
+     *   $stack->push($middleware);
+     *
+     *   $client = new Client([
+     *       'handler' => $stack,
+     *       'base_url' => 'https://www.googleapis.com/taskqueue/v1beta2/projects/',
+     *       'auth' => 'scoped' // authorize all requests
+     *   ]);
+     *
+     *   $res = $client->get('myproject/taskqueues/myqueue');
+     *
+     * @param callable $handler
+     *
+     * @return \Closure
+     */
+    public function __invoke(callable $handler)
+    {
+        return function (RequestInterface $request, array $options) use ($handler) {
+            // Requests using "auth"="scoped" will be authorized.
+            if (!isset($options['auth']) || $options['auth'] !== 'scoped') {
+                return $handler($request, $options);
+            }
+
+            $request = $request->withHeader('authorization', 'Bearer ' . $this->fetchToken());
+
+            return $handler($request, $options);
+        };
+    }
+
+    /**
+     * @return string
+     */
+    private function getCacheKey()
+    {
+        $key = null;
+
+        if (is_string($this->scopes)) {
+            $key .= $this->scopes;
+        } elseif (is_array($this->scopes)) {
+            $key .= implode(':', $this->scopes);
+        }
+
+        return $key;
+    }
+
+    /**
+     * Determine if token is available in the cache, if not call tokenFunc to
+     * fetch it.
+     *
+     * @return string
+     */
+    private function fetchToken()
+    {
+        $cacheKey = $this->getCacheKey();
+        $cached = $this->getCachedValue($cacheKey);
+
+        if (!empty($cached)) {
+            return $cached;
+        }
+
+        $token = call_user_func($this->tokenFunc, $this->scopes);
+        $this->setCachedValue($cacheKey, $token);
+
+        return $token;
+    }
+}

vendor/google/auth/src/Middleware/SimpleMiddleware.php

@@ -0,0 +1,93 @@
+<?php
+/*
+ * Copyright 2015 Google Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License 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 Google\Auth\Middleware;
+
+use GuzzleHttp\Psr7;
+use Psr\Http\Message\RequestInterface;
+
+/**
+ * SimpleMiddleware is a Guzzle Middleware that implements Google's Simple API
+ * access.
+ *
+ * Requests are accessed using the Simple API access developer key.
+ */
+class SimpleMiddleware
+{
+    /**
+     * @var array
+     */
+    private $config;
+
+    /**
+     * Create a new Simple plugin.
+     *
+     * The configuration array expects one option
+     * - key: required, otherwise InvalidArgumentException is thrown
+     *
+     * @param array $config Configuration array
+     */
+    public function __construct(array $config)
+    {
+        if (!isset($config['key'])) {
+            throw new \InvalidArgumentException('requires a key to have been set');
+        }
+
+        $this->config = array_merge(['key' => null], $config);
+    }
+
+    /**
+     * Updates the request query with the developer key if auth is set to simple.
+     *
+     *   use Google\Auth\Middleware\SimpleMiddleware;
+     *   use GuzzleHttp\Client;
+     *   use GuzzleHttp\HandlerStack;
+     *
+     *   $my_key = 'is not the same as yours';
+     *   $middleware = new SimpleMiddleware(['key' => $my_key]);
+     *   $stack = HandlerStack::create();
+     *   $stack->push($middleware);
+     *
+     *   $client = new Client([
+     *       'handler' => $stack,
+     *       'base_uri' => 'https://www.googleapis.com/discovery/v1/',
+     *       'auth' => 'simple'
+     *   ]);
+     *
+     *   $res = $client->get('drive/v2/rest');
+     *
+     * @param callable $handler
+     *
+     * @return \Closure
+     */
+    public function __invoke(callable $handler)
+    {
+        return function (RequestInterface $request, array $options) use ($handler) {
+            // Requests using "auth"="scoped" will be authorized.
+            if (!isset($options['auth']) || $options['auth'] !== 'simple') {
+                return $handler($request, $options);
+            }
+
+            $query = Psr7\parse_query($request->getUri()->getQuery());
+            $params = array_merge($query, $this->config);
+            $uri = $request->getUri()->withQuery(Psr7\build_query($params));
+            $request = $request->withUri($uri);
+
+            return $handler($request, $options);
+        };
+    }
+}

vendor/google/auth/src/ServiceAccountSignerTrait.php

@@ -0,0 +1,57 @@
+<?php
+/*
+ * Copyright 2019 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License 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 Google\Auth;
+
+use phpseclib\Crypt\RSA;
+
+/**
+ * Sign a string using a Service Account private key.
+ */
+trait ServiceAccountSignerTrait
+{
+    /**
+     * Sign a string using the service account private key.
+     *
+     * @param string $stringToSign
+     * @param bool $forceOpenssl Whether to use OpenSSL regardless of
+     *        whether phpseclib is installed. **Defaults to** `false`.
+     * @return string
+     */
+    public function signBlob($stringToSign, $forceOpenssl = false)
+    {
+        $privateKey = $this->auth->getSigningKey();
+
+        $signedString = '';
+        if (class_exists('RSA') && !$forceOpenssl) {
+            $rsa = new RSA;
+            $rsa->loadKey($privateKey);
+            $rsa->setSignatureMode(RSA::SIGNATURE_PKCS1);
+            $rsa->setHash('sha256');
+
+            $signedString = $rsa->sign($stringToSign);
+        } elseif (extension_loaded('openssl')) {
+            openssl_sign($stringToSign, $signedString, $privateKey, 'sha256WithRSAEncryption');
+        } else {
+            // @codeCoverageIgnoreStart
+            throw new \RuntimeException('OpenSSL is not installed.');
+        }
+        // @codeCoverageIgnoreEnd
+
+        return base64_encode($signedString);
+    }
+}

vendor/google/auth/src/SignBlobInterface.php

@@ -0,0 +1,44 @@
+<?php
+/*
+ * Copyright 2019 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License 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 Google\Auth;
+
+/**
+ * Describes a class which supports signing arbitrary strings.
+ */
+interface SignBlobInterface extends FetchAuthTokenInterface
+{
+    /**
+     * Sign a string using the method which is best for a given credentials type.
+     *
+     * @param string $stringToSign The string to sign.
+     * @param bool $forceOpenssl Require use of OpenSSL for local signing. Does
+     *        not apply to signing done using external services. **Defaults to**
+     *        `false`.
+     * @return string The resulting signature. Value should be base64-encoded.
+     */
+    public function signBlob($stringToSign, $forceOpenssl = false);
+
+    /**
+     * Returns the current Client Name.
+     *
+     * @param callable $httpHandler callback which delivers psr7 request, if
+     *     one is required to obtain a client name.
+     * @return string
+     */
+    public function getClientName(callable $httpHandler = null);
+}

vendor/google/auth/src/Subscriber/AuthTokenSubscriber.php

@@ -0,0 +1,118 @@
+<?php
+/*
+ * Copyright 2015 Google Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License 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 Google\Auth\Subscriber;
+
+use Google\Auth\FetchAuthTokenInterface;
+use GuzzleHttp\Event\BeforeEvent;
+use GuzzleHttp\Event\RequestEvents;
+use GuzzleHttp\Event\SubscriberInterface;
+
+/**
+ * AuthTokenSubscriber is a Guzzle Subscriber that adds an Authorization header
+ * provided by an object implementing FetchAuthTokenInterface.
+ *
+ * The FetchAuthTokenInterface#fetchAuthToken is used to obtain a hash; one of
+ * the values value in that hash is added as the authorization header.
+ *
+ * Requests will be accessed with the authorization header:
+ *
+ * 'authorization' 'Bearer <value of auth_token>'
+ */
+class AuthTokenSubscriber implements SubscriberInterface
+{
+    /**
+     * @var callable
+     */
+    private $httpHandler;
+
+    /**
+     * @var FetchAuthTokenInterface
+     */
+    private $fetcher;
+
+    /**
+     * @var callable
+     */
+    private $tokenCallback;
+
+    /**
+     * Creates a new AuthTokenSubscriber.
+     *
+     * @param FetchAuthTokenInterface $fetcher is used to fetch the auth token
+     * @param callable $httpHandler (optional) http client to fetch the token.
+     * @param callable $tokenCallback (optional) function to be called when a new token is fetched.
+     */
+    public function __construct(
+        FetchAuthTokenInterface $fetcher,
+        callable $httpHandler = null,
+        callable $tokenCallback = null
+    ) {
+        $this->fetcher = $fetcher;
+        $this->httpHandler = $httpHandler;
+        $this->tokenCallback = $tokenCallback;
+    }
+
+    /**
+     * @return array
+     */
+    public function getEvents()
+    {
+        return ['before' => ['onBefore', RequestEvents::SIGN_REQUEST]];
+    }
+
+    /**
+     * Updates the request with an Authorization header when auth is 'fetched_auth_token'.
+     *
+     *   use GuzzleHttp\Client;
+     *   use Google\Auth\OAuth2;
+     *   use Google\Auth\Subscriber\AuthTokenSubscriber;
+     *
+     *   $config = [..<oauth config param>.];
+     *   $oauth2 = new OAuth2($config)
+     *   $subscriber = new AuthTokenSubscriber($oauth2);
+     *
+     *   $client = new Client([
+     *      'base_url' => 'https://www.googleapis.com/taskqueue/v1beta2/projects/',
+     *      'defaults' => ['auth' => 'google_auth']
+     *   ]);
+     *   $client->getEmitter()->attach($subscriber);
+     *
+     *   $res = $client->get('myproject/taskqueues/myqueue');
+     *
+     * @param BeforeEvent $event
+     */
+    public function onBefore(BeforeEvent $event)
+    {
+        // Requests using "auth"="google_auth" will be authorized.
+        $request = $event->getRequest();
+        if ($request->getConfig()['auth'] != 'google_auth') {
+            return;
+        }
+
+        // Fetch the auth token.
+        $auth_tokens = $this->fetcher->fetchAuthToken($this->httpHandler);
+        if (array_key_exists('access_token', $auth_tokens)) {
+            $request->setHeader('authorization', 'Bearer ' . $auth_tokens['access_token']);
+
+            // notify the callback if applicable
+            if ($this->tokenCallback) {
+                call_user_func($this->tokenCallback, $this->fetcher->getCacheKey(), $auth_tokens['access_token']);
+            }
+        }
+    }
+}

vendor/google/auth/src/Subscriber/ScopedAccessTokenSubscriber.php

@@ -0,0 +1,177 @@
+<?php
+/*
+ * Copyright 2015 Google Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License 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 Google\Auth\Subscriber;
+
+use Google\Auth\CacheTrait;
+use GuzzleHttp\Event\BeforeEvent;
+use GuzzleHttp\Event\RequestEvents;
+use GuzzleHttp\Event\SubscriberInterface;
+use Psr\Cache\CacheItemPoolInterface;
+
+/**
+ * ScopedAccessTokenSubscriber is a Guzzle Subscriber that adds an Authorization
+ * header provided by a closure.
+ *
+ * The closure returns an access token, taking the scope, either a single
+ * string or an array of strings, as its value.  If provided, a cache will be
+ * used to preserve the access token for a given lifetime.
+ *
+ * Requests will be accessed with the authorization header:
+ *
+ * 'authorization' 'Bearer <access token obtained from the closure>'
+ */
+class ScopedAccessTokenSubscriber implements SubscriberInterface
+{
+    use CacheTrait;
+
+    const DEFAULT_CACHE_LIFETIME = 1500;
+
+    /**
+     * @var CacheItemPoolInterface
+     */
+    private $cache;
+
+    /**
+     * @var callable The access token generator function
+     */
+    private $tokenFunc;
+
+    /**
+     * @var array|string The scopes used to generate the token
+     */
+    private $scopes;
+
+    /**
+     * @var array
+     */
+    private $cacheConfig;
+
+    /**
+     * Creates a new ScopedAccessTokenSubscriber.
+     *
+     * @param callable $tokenFunc a token generator function
+     * @param array|string $scopes the token authentication scopes
+     * @param array $cacheConfig configuration for the cache when it's present
+     * @param CacheItemPoolInterface $cache an implementation of CacheItemPoolInterface
+     */
+    public function __construct(
+        callable $tokenFunc,
+        $scopes,
+        array $cacheConfig = null,
+        CacheItemPoolInterface $cache = null
+    ) {
+        $this->tokenFunc = $tokenFunc;
+        if (!(is_string($scopes) || is_array($scopes))) {
+            throw new \InvalidArgumentException(
+                'wants scope should be string or array');
+        }
+        $this->scopes = $scopes;
+
+        if (!is_null($cache)) {
+            $this->cache = $cache;
+            $this->cacheConfig = array_merge([
+                'lifetime' => self::DEFAULT_CACHE_LIFETIME,
+                'prefix' => '',
+            ], $cacheConfig);
+        }
+    }
+
+    /**
+     * @return array
+     */
+    public function getEvents()
+    {
+        return ['before' => ['onBefore', RequestEvents::SIGN_REQUEST]];
+    }
+
+    /**
+     * Updates the request with an Authorization header when auth is 'scoped'.
+     *
+     *   E.g this could be used to authenticate using the AppEngine
+     *   AppIdentityService.
+     *
+     *   use google\appengine\api\app_identity\AppIdentityService;
+     *   use Google\Auth\Subscriber\ScopedAccessTokenSubscriber;
+     *   use GuzzleHttp\Client;
+     *
+     *   $scope = 'https://www.googleapis.com/auth/taskqueue'
+     *   $subscriber = new ScopedAccessToken(
+     *       'AppIdentityService::getAccessToken',
+     *       $scope,
+     *       ['prefix' => 'Google\Auth\ScopedAccessToken::'],
+     *       $cache = new Memcache()
+     *   );
+     *
+     *   $client = new Client([
+     *       'base_url' => 'https://www.googleapis.com/taskqueue/v1beta2/projects/',
+     *       'defaults' => ['auth' => 'scoped']
+     *   ]);
+     *   $client->getEmitter()->attach($subscriber);
+     *
+     *   $res = $client->get('myproject/taskqueues/myqueue');
+     *
+     * @param BeforeEvent $event
+     */
+    public function onBefore(BeforeEvent $event)
+    {
+        // Requests using "auth"="scoped" will be authorized.
+        $request = $event->getRequest();
+        if ($request->getConfig()['auth'] != 'scoped') {
+            return;
+        }
+        $auth_header = 'Bearer ' . $this->fetchToken();
+        $request->setHeader('authorization', $auth_header);
+    }
+
+    /**
+     * @return string
+     */
+    private function getCacheKey()
+    {
+        $key = null;
+
+        if (is_string($this->scopes)) {
+            $key .= $this->scopes;
+        } elseif (is_array($this->scopes)) {
+            $key .= implode(':', $this->scopes);
+        }
+
+        return $key;
+    }
+
+    /**
+     * Determine if token is available in the cache, if not call tokenFunc to
+     * fetch it.
+     *
+     * @return string
+     */
+    private function fetchToken()
+    {
+        $cacheKey = $this->getCacheKey();
+        $cached = $this->getCachedValue($cacheKey);
+
+        if (!empty($cached)) {
+            return $cached;
+        }
+
+        $token = call_user_func($this->tokenFunc, $this->scopes);
+        $this->setCachedValue($cacheKey, $token);
+
+        return $token;
+    }
+}

vendor/google/auth/src/Subscriber/SimpleSubscriber.php

@@ -0,0 +1,90 @@
+<?php
+/*
+ * Copyright 2015 Google Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License 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 Google\Auth\Subscriber;
+
+use GuzzleHttp\Event\BeforeEvent;
+use GuzzleHttp\Event\RequestEvents;
+use GuzzleHttp\Event\SubscriberInterface;
+
+/**
+ * SimpleSubscriber is a Guzzle Subscriber that implements Google's Simple API
+ * access.
+ *
+ * Requests are accessed using the Simple API access developer key.
+ */
+class SimpleSubscriber implements SubscriberInterface
+{
+    /**
+     * @var array
+     */
+    private $config;
+
+    /**
+     * Create a new Simple plugin.
+     *
+     * The configuration array expects one option
+     * - key: required, otherwise InvalidArgumentException is thrown
+     *
+     * @param array $config Configuration array
+     */
+    public function __construct(array $config)
+    {
+        if (!isset($config['key'])) {
+            throw new \InvalidArgumentException('requires a key to have been set');
+        }
+
+        $this->config = array_merge([], $config);
+    }
+
+    /**
+     * @return array
+     */
+    public function getEvents()
+    {
+        return ['before' => ['onBefore', RequestEvents::SIGN_REQUEST]];
+    }
+
+    /**
+     * Updates the request query with the developer key if auth is set to simple.
+     *
+     *   use Google\Auth\Subscriber\SimpleSubscriber;
+     *   use GuzzleHttp\Client;
+     *
+     *   $my_key = 'is not the same as yours';
+     *   $subscriber = new SimpleSubscriber(['key' => $my_key]);
+     *
+     *   $client = new Client([
+     *      'base_url' => 'https://www.googleapis.com/discovery/v1/',
+     *      'defaults' => ['auth' => 'simple']
+     *   ]);
+     *   $client->getEmitter()->attach($subscriber);
+     *
+     *   $res = $client->get('drive/v2/rest');
+     *
+     * @param BeforeEvent $event
+     */
+    public function onBefore(BeforeEvent $event)
+    {
+        // Requests using "auth"="simple" with the developer key.
+        $request = $event->getRequest();
+        if ($request->getConfig()['auth'] != 'simple') {
+            return;
+        }
+        $request->getQuery()->overwriteWith($this->config);
+    }
+}