Everyone should know that in the WordPress admin interface you can set a single password to make a post visible only to the people who knows such password.
But what if you need a more permissive set of rules to show the post content?
For example you want to show a promotional code for your shop only to the owners of a specific card.
The card has an ID on it and every ID is made of two letters plus 9 numbers.
Here’s my solution:
This solution stores an hashed fake password (yesyoucan) in a cookie so that the first time you enter your card ID, it will be remember for 10 days.