The "Custom" payment gateway
This guide is incomplete. Please help us complete it using the "Edit this page" button in the sidebar. Thanks! If you're looking to create your own extension, this documentation will tell you the bare minimum required, but looking at existing extensions will probably be necessary to get a complete idea on how to write one.
The "Custom" payment gateway in FOSSBilling is a generic payment gateway which can be used as a last resort. The gateway itself provides no way to handle payments and only acts as a method to display instructions to your client so that you may manually process a transaction.
Templates
When entering a custom template for the custom payment gateway, you should know that it's powered by twig and has the same twig filters and functions (opens in a new tab) as the rest of the software does.
Some basic variables (opens in a new tab) are passed to twig, allowing you to display some additional information to the client.
To view the contents of the invoice variable, edit your config.php file to enable debug mode for twig and then place the following contents into your template:
<pre>
{{ dump(invoice) }}
</pre>Be sure to disable debug mode for twig once you are done.