PHP Notices for undefined constants

[jphorn]

Describe the bug
PHP warnings for undefined constants LOGGED_IN_KEY and LOGGED_IN_SALT.

To Reproduce
Steps to reproduce the behavior:

1. Install Site Kit plugin
2. Enable PHP error logging
3. Activate Site Kit plugin in WordPress
4. Many PHP warning notices for undefined constants

Warning: Use of undefined constant LOGGED_IN_KEY - assumed 'LOGGED_IN_KEY' (this will throw an Error in a future version of PHP) in example.com/wp-content/plugins/google-site-kit/includes/Core/Storage/Data_Encryption.php on line 118

Warning: Use of undefined constant LOGGED_IN_KEY - assumed 'LOGGED_IN_KEY' (this will throw an Error in a future version of PHP) in example.com/wp-content/plugins/google-site-kit/includes/Core/Storage/Data_Encryption.php on line 119

Warning: Use of undefined constant LOGGED_IN_SALT - assumed 'LOGGED_IN_SALT' (this will throw an Error in a future version of PHP) in example.com/wp-content/plugins/google-site-kit/includes/Core/Storage/Data_Encryption.php on line 138

Warning: Use of undefined constant LOGGED_IN_SALT - assumed 'LOGGED_IN_SALT' (this will throw an Error in a future version of PHP) in example.com/wp-content/plugins/google-site-kit/includes/Core/Storage/Data_Encryption.php on line 139

Warning: Use of undefined constant LOGGED_IN_KEY - assumed 'LOGGED_IN_KEY' (this will throw an Error in a future version of PHP) in example.com/wp-content/plugins/google-site-kit/includes/Core/Storage/Data_Encryption.php on line 118

Warning: Use of undefined constant LOGGED_IN_KEY - assumed 'LOGGED_IN_KEY' (this will throw an Error in a future version of PHP) in example.com/wp-content/plugins/google-site-kit/includes/Core/Storage/Data_Encryption.php on line 119

Warning: Use of undefined constant LOGGED_IN_SALT - assumed 'LOGGED_IN_SALT' (this will throw an Error in a future version of PHP) in example.com/wp-content/plugins/google-site-kit/includes/Core/Storage/Data_Encryption.php on line 138

Warning: Use of undefined constant LOGGED_IN_SALT - assumed 'LOGGED_IN_SALT' (this will throw an Error in a future version of PHP) in example.com/wp-content/plugins/google-site-kit/includes/Core/Storage/Data_Encryption.php on line 139

Warning: Use of undefined constant LOGGED_IN_KEY - assumed 'LOGGED_IN_KEY' (this will throw an Error in a future version of PHP) in example.com/wp-content/plugins/google-site-kit/includes/Core/Storage/Data_Encryption.php on line 118

Warning: Use of undefined constant LOGGED_IN_KEY - assumed 'LOGGED_IN_KEY' (this will throw an Error in a future version of PHP) in example.com/wp-content/plugins/google-site-kit/includes/Core/Storage/Data_Encryption.php on line 119

Warning: Use of undefined constant LOGGED_IN_SALT - assumed 'LOGGED_IN_SALT' (this will throw an Error in a future version of PHP) in example.com/wp-content/plugins/google-site-kit/includes/Core/Storage/Data_Encryption.php on line 138

Warning: Use of undefined constant LOGGED_IN_SALT - assumed 'LOGGED_IN_SALT' (this will throw an Error in a future version of PHP) in example.com/wp-content/plugins/google-site-kit/includes/Core/Storage/Data_Encryption.php on line 139

Warning: Use of undefined constant LOGGED_IN_KEY - assumed 'LOGGED_IN_KEY' (this will throw an Error in a future version of PHP) in example.com/wp-content/plugins/google-site-kit/includes/Core/Storage/Data_Encryption.php on line 118

Warning: Use of undefined constant LOGGED_IN_KEY - assumed 'LOGGED_IN_KEY' (this will throw an Error in a future version of PHP) in example.com/wp-content/plugins/google-site-kit/includes/Core/Storage/Data_Encryption.php on line 119

Warning: Use of undefined constant LOGGED_IN_SALT - assumed 'LOGGED_IN_SALT' (this will throw an Error in a future version of PHP) in example.com/wp-content/plugins/google-site-kit/includes/Core/Storage/Data_Encryption.php on line 138

Warning: Use of undefined constant LOGGED_IN_SALT - assumed 'LOGGED_IN_SALT' (this will throw an Error in a future version of PHP) in example.com/wp-content/plugins/google-site-kit/includes/Core/Storage/Data_Encryption.php on line 139

Warning: Cannot modify header information - headers already sent by (output started at example.com/wp-content/plugins/google-site-kit/includes/Core/Storage/Data_Encryption.php:138) in example.com/wp-admin/includes/misc.php on line 1196

More information and proposed fix.

System Information (please complete the following information):

• PHP Version: 7.2.14
• OS: macOS (Mamp Pro)
• Browser Safari 12.1.1/macOS
• Plugin Version: 1.0.0.beta.1
• Device: MacBook Pro 2018

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Changelog entry

• Check if LOGGED_IN_KEY and LOGGED_IN_SALT are defined before using it, to account for some environments such as local ones.

Acceptance criteria

[jamesozzie]

Thanks for the context, will pass this on now.

[ivankristianto]

Fixed in #32

@jphorn thanks for reporting this issue. I hope your site is a staging or local environment. But if you have this error on your production site, please consider to add the WordPress salt in your wp-config.php file, https://api.wordpress.org/secret-key/1.1/salt/

[jphorn]

@ivankristianto Yes, this is a local development server :-) Thank you for the fix and feedback.

[ThierryA]

@bjackson27 has this been QA'ed?