Feature request: Don't return null values from groq query

eivindml commented 2 years ago

For some applications, I like to use a runtime type system so I can decode the query responses from Sanity, and have a 100% runtime guarantee of correct types. One issue I'm often bumping into with regards to this, is that Sanity returns optional empty values as null.

If my decoder tries to decode the value:

type Link = {
  title: string;
  label?: string;
}

It can fail, since my label type is label?: string while Sanity basically returns label: string | null, but only for some queries.

Example:

If I do a query like this;

*[_type == "link"] {
  _id,
  title,
  label
}

the "optional" label will return a value if string | null. It would be better to not return it at all, or return it as undefined.

If I use the ... syntax like this;

*[_type == "link"] {
  ...
}

I get the result I prefer, but now I'm querying unnecessary data.

I learnt that I can use the defined(), and it works, but it's a bit verbose, I have to apply that to all optional fields.

*[_type == "resource"] {
  _id,
    "slug": slug.current,
    title,
    defined(subtitle) => {subtitle},
    defined(content) => {content},
    description,
    defined(keywords) => {keywords},
    defined(video.url) => {"video": video.url},
    "asset": {
      defined(external) => {"external": asset.external},
      defined(internal) => {"internal": asset.internal.asset->url}
    },
    categories[]->{_id, title},
   "poster": poster.asset-> {
     ...,
     "lqip": metadata.lqip
   }
}

Describe the solution you'd like

It would be nice to be able to specify this behaviour at the top level of the groq query (or something similar).

*[_type == "resource"] | defined(*) {
  _id,
    "slug": slug.current,
    title,
}

Describe alternatives you've considered

Currently I'm sprinkling in defined() everywhere.
I've also considered crating a transform function, that can be applied to all responses, that will strip out any value that is null