Documentation on how to create a resolver with query filtering

[jasonbiondo]

Can someone explain how to create a resolver for something like limiting the amount of images returned in query. Lets assume you have

node -> images -> src

and I want to do

node -> images(limit: 2) -> src

so only 2 images would be queryied via graphql. How can we create these subfilters? I. assume it's with a resolver but I see no example of this in the docs.

[pvdz]

Hi @jasonbiondo . I'm going to convert your issue to a discussion :)

[jasonbiondo]

@pvdz Thank you but does anyone know how to do this?

[vladar]

You can do this with custom resolvers using createResolvers API. See those links for some examples:

https://www.gatsbyjs.com/docs/node-apis/#createResolvers
https://github.com/gatsbyjs/gatsby/blob/master/examples/using-type-definitions/gatsby-node.js

Also in blog posts:
https://www.gatsbyjs.com/blog/2019-03-04-new-schema-customization/
https://www.gatsbyjs.com/blog/2019-03-18-releasing-new-schema-customization/

Also given your description, something like this will probably work:

// in gatsby-node
exports.createResolvers = ({ createResolvers }) => {
  createResolvers({
    NodeType: {
      images: {
        args: { limit: `Int` },
        resolve: async (root, args, context, info) => {
          const allImages = await info.originalResolver(root, args, context, info) || []
          return args.limit ? allImages.slice(0, args.limit) : allImages
        }
      }
    }
  })
}