[FEATURE] - default values for input schema for Server Actions

[billy-le]

Astro Info

Astro                    v4.13.1
Node                     v22.4.0
System                   macOS (arm64)
Package Manager          unknown
Output                   server
Adapter                  @astrojs/node
Integrations             @clerk/astro/integration
                         @astrojs/react
                         @astrojs/tailwind
                         astro:db
                         @astrojs/db/file-url

If this issue only occurs in one browser, which browser is a problem?

No response

Describe the Bug

I have a FormSchema, that I use for the client and on the server. The input for a server action doesn't return a default value where I was expecting it. I discovered this because I wanted to pass in an array of Files to upload to a bucket but the server kept saying that my input for images is invalid.

So I did a little investigation and found the part that would fix my use case and opened a PR. I've since taken it down so I'm raising this issue instead.

Ultimately, what I wanted was a list of Files from the client in the server action and it was throwing an error because the .default() method was not being handled.

export const PropertyFormSchema = z.object({
  images: z.array(z.instanceof(File)).default([]),
});

defineAction({
    accept: "form",
    input: PropertyFormSchema,
    handler: async (input, context) => {}
})

What's the expected result?

I expected this input to handle this correctly:

z.array(z.instanceof(File)).default([]) to return an empty array or a list of Files.

Link to Minimal Reproducible Example

https://stackblitz.com/edit/github-7qnawk?file=src%2Fcomponents%2FPropertyForm.tsx

Couldn't reproduce on stackblitz. Seems like I can't perform server actions on there.

Participation

• I am willing to submit a pull request for this issue.

[bholmesdev]

Thanks for reporting this @billy-le! Yes, it looks like default values on form inputs aren't handled correctly. I checked that PR you linked, and I'm honestly happy to reopen and leave a few review comments before merging. Would you be open to that?

[billy-le]

@bholmesdev for sure! I am thrilled to be contributing. Looking forward to your comments. Thanks!