Customizing FOSSBilling
Customizing Invoice PDFs

Customizing Invoice PDFs

Invoice CSS

During the PDF generation, FOSSBilling first creates a simple HTML page and then converts that to a PDF using dompdf (opens in a new tab). The HTML page cannot currently be edited without editing the invoice module's source code, however you may use custom CSS for the page.


One important note to make, is that dompdf does not offer complete CSS support. Here is the limitations for dompdf as of version 2.0.3:

  • Handles most CSS 2.1 and a few CSS3 properties, including @import, @media & @page rules
  • Table cells are not pageable, meaning a table row must fit on a single page.
  • Elements are rendered on the active page when they are parsed.
  • Does not support CSS flexbox.
  • Does not support CSS Grid.

Using custom CSS

By default, FOSSBilling uses the CSS from /modules/Invoice/pdf_template/default-pdf.css, however if you edit this file, any changes to it will be overridden when you update FOSSBilling.

Simply make a copy of the default-pdf.css file and place it under /modules/Invoice/pdf_template/custom-pdf.css. This new custom CSS file will be used instead of the original one, and it will not be overridden when you update FOSSBilling. You can now edit the custom-pdf.css file and use custom CSS for the PDF generation, keeping in mind the limitations described above.

The layout

Please see the image below for information on the overall layout of the page and where CSS classes are used (color-coded): Layout of the PDF page

Invoice HTML

This section is a WIP and will be improved over time Starting with FOSSBilling version 0.6.0, you can modify the template used to generate PDFs.

Technology used

Just like the FOSSBilling front-end, PDFs are generated utilizing twig-based templates. This twig instance is configured the same as other options of FOSSBilling, meaning that the same filters are available.

Using a custom HTML template

The default template FOSSBilling will utilize is /modules/Invoice/pdf_template/default-pdf.twig. If you want to use a custom one, create one under /modules/Invoice/pdf_template/custom-pdf.twig which will then be used instead of the default template.

Twig Filters and Functions

Invoices gain access to the same filters that Twig does on the front-end with FOSSBilling. You may find a list of these on the Twig Filters & Functions (opens in a new tab) page.