FIG. 05 · Project
Directus Auto Gen
An extension that derives a field from the values an editor already entered. A title can become a slug, and a pair of numbers can become a total.
The problem
Entering a title and then retyping its slug is small work that repeats on every item. Manual copies also drift: the title changes, the derived field stays behind.
My role
I authored the Auto Gen extension for Directus and documented its formula and template options. I’m a Directus Builders member.
The key decision
Let editors configure a readable formula next to the field. The interface shows the result as they edit. A server hook can apply the same evaluation when a configured item is written through the API.
The result
The package is available on npm and the examples are inspectable in the public repository. The useful result is concrete: give the field one source value, and it derives a repeatable output.
Visual evidence
One input, a derived field.
Two small examples show why the extension exists: calculate from fields an editor already has, with the rule visible beside the result.
01 / Worked example
Turn a title into a slug
A title supplies the human-readable text. The slug rule supplies a predictable URL fragment. This example uses sample content.
View full size See the formula reference
02 / Worked example
Calculate an item total
The same idea works with numbers. Change the quantity or unit price and the rule calculates a new total.
View full size View the npm package