feat: use custom status codes in SSR & DSG response

[chrisq21]

The DSG & SSR handler uses the serverDataStatus value to use custom status codes. Defaults to 200

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[ascorbic]

Thanks for this! Looking good so far. The issue seems to be with the types for getData. Would this be fixed by updating the version of Gatsby in the demo site, or are the types missing from Gatsby?

[chrisq21]

Happy to contribute!

Yeah the ISSRData type defined here contains serverDataStatus, but ISSRData in the type declaration file doesn't expose serverDataStatus.

@ascorbic Would you recommend creating a PR in the gatsby repo to include serverDataStatus in the type declaration file as a pre-requisite for this PR, or some other approach? I noticed that the gatsby-plugin-fastify plugin was able to reference serverDataStatus in this update so wasn't sure if I was missing something.

[ascorbic]

I would do a PR to Gatsby (apart from anything, they'll send you some great swag if you do!). However if you don't want to wait, we did previously define our own types while we waited for them to update the published types, so you might want to do similar here.

[chrisq21]

Sounds good! This can wait a bit so I'll go ahead and make a PR into the Gatsby repo.

[ascorbic]

Great! I recommend the jamstack jammies 😄

[manuelJung]

any updates on this? this feature is essential to work with gatsby ssr on netlify. without we cannot send a 404 statuscode