Prisma plugin - t.relation resolve to a single record?

[PatricioNG]

Wondering if there's a way to do a resolver for a relation field? Use case: a table of metadata, I have a field called metadata where you can resolve it all, but I wanted to expose metafield with an arg to query just a single metadata record and return it instead of an array

Currently I am doing this which returns the record as the first index of an array:

... //Rest of the prismaObject type definition

metafield: t.relation('Metadata', {
			args: {
				key: t.arg.string({ required: true }),
			},
			query: ({ key }) => ({
				where: {
					key,
				},
			}),
		}),

Was hoping for something like:

metafield: t.relation('Metadata', {
			args: {
				key: t.arg.string({ required: true }),
			},
			query: ({ key }) => ({
				where: {
					key,
				},
			}),
			nullable: true,
			resolve(_query, {Metadata}, args, context, info) {
				return Metadata[0] ?? null
			},
		}),

[hayes]

You can use t.field with select for this. Something like this is probably what you are looking for:

const MetadataRef = builder.prismaObject('Metadata', { /* ... */ })

// ...
(t) => ({
  metafield: t.field({
    type: MetadataRef,
    nullable: true,
    args: {
      key: t.arg.string({ required: true }),
    },
    select: ({ key }, ctx, nestedSelection) => ({
      Metadata: nestedSelection({
        where: {
          key,
        }
      })
    }),
    resolve({ Metadata }, args, context, info) {
      return Metadata[0] ?? null;
    },
  }),
});

[PatricioNG]

Ah incredible, thanks @hayes! Appreciate how responsive you are for this, it's super helpful! 🙏 🙌

[hayes]

No problem. If you have time, I'm looking for people willing to go through the 4.0 migration before the final release to get some feedback and make sure the important stuff is all covered: https://v4.pothos-graphql.dev/docs/migrations/v4