Selection

The way to select fields.

Specification

Depends on the field type, the selection can be true or TypeSelection.

• true: Select a scalar field or an enum field.
• TypeSelection: Select a TypeObject field.

At the beginning you need select the fields from the type object Query, Mutation or Subscription. It means it required a TypeSelection on root of the query.

const query = gqfn([])

TypeSelection is an array, it can contain the list of names of fields to select, and the last item can be a record for these fields which are type object or you need to pass arguments.

Query Builder

const query = gqfn([
  'a',
  'b',
  {
    c: true,
  }
])

Another

const query = gqfn([{
  a: true,
  b: true,
  c: true,
}])

GraphQL Query

{
  a
  b
  c
}

You can use {alias}:{field} to select a field with an alias.

Query Builder

const query = gqfn([
  'hi:hello',
])

GraphQL Query

{
  hi: hello
}

If you want to pass arguments to a field, you can use the $ function.

Query Builder

const query = gqfn([
  {
    hello: $ => $({ name: 'Tom' }, true)
  }
])

GraphQL Query

{
  hello(name: "Tom")
}

In the previous example, the selected fields returns a scalar value, but if you want to select a TypeObject field, you can pass a TypeSelection as the second argument of the $ function.

Query Builder

const query = gqfn([
  {
    user: $ => $({ id: 1 }, [
      'id',
      'name',
      'email',
    ])
  }
])

GraphQL Query

{
  user(id: 1) {
    id
    name
    email
  }
}

Or for simplify you can pass the TypeSelection as the only argument.

Query Builder

const query = gqfn([
  {
    users: $ => $([
      'id',
      'name',
      'email',
    ])
  }
])

GraphQL Query

{
  users {
    id
    name
    email
  }
}

Learn more about $ and dollar function.

Type Definition

TIP

The type definition is not complete, it only shows the basic structure of the TypeSelection type.

export type TypeSelection =
  | Array<string>
  | [
    ...Array<string>,
    SelectionObject,
  ]

interface SelectionObject {
  [key: string]:
    | true
    | (($: Dollar) => DollarContext<TypeSelection>)
}