I’m having trouble to find good documentation about how to use Netlify Functions with multipart/form-data. This blog post is the best I found but I does not work as is:
Could you please point me in the right direction how you would approach this. In my opinion this is a common use-case and should be well documented!
That’s a bit odd - typically folks submit the form to our form handling service, so this is what all of our docs are about. The only way most folks use functions with forms, is event-triggered functions: Trigger functions on events | Netlify Docs
When we notify an event-triggered function, the data is in JSON, not multipart/form-data format, so you wouldn’t use this workflow in normal operations at Netlify.
Our staff doesn’t have any other samples to share than that one you linked, but maybe someone else in the community will.