Queries and Mutations

The datalayer consists of entry-points which we will use to fulfill our data-requirements, often when we start a new page we'll need to either use an existing entry-point or create a new one.

For retrieving data one or more of those entry-points can be created with the addQueryFields function.

addQueryFields(t => ({
  me: t.field({
    type: UserNode,
    resolve: (parent, args, context) => context.userId
  })
}))

The above could for instance be an entry-point for a profile page or any page that has a menu-dropdown welcoming the user.

Our datalayer should also be able to manipulate data, these are referred to as mutations and can be added similarly to query entry-points by means of addMutationFields.

addMutationFields(t => ({
  updateUserName: t.field({
    type: UserNode,
    args: {
      userName: t.arg.string({ required: true })
    }
    resolve: (parent, args, context) => {
      // Some logic to update the username of our current user with args.userName
    }
  })
}))

Now we have an entry-point to retrieve our own user and to manipulate our username!

Arguments

As you can see in the above examples we can define arguments for our entry-points, these arguments are optional by default and can be made required by means of { required: true }. All scalar values have their own t.arg which can be used to define arguments on a field, just to sum these up:

id
string
boolean
int
float

Most of these also have a *List equivalent to indicate you will pass an array of that scalar type.

We won't always be passing in scalar-values and we might even want to re-use certain inputs for multiple fields, like for example a PaginationInput which we can use on any field we paginate over. We can do this by importing inputType from fuse and creating one as followed

const PaginationInput = inputType({
  name: 'PaginationInput',
  fields: (t) => ({
    offset: t.int({ defaultValue: 0 }),
    limit: t.int({ defaultValue: 10 }),
  }),
})

Now when we want to use PaginationInput we can pass it to t.arg, for example { pagination: t.arg({ type: PaginationInput }) }.

Now we can pass this input to our fields accepting these arguments!

Nodes Handling lists