chore(gatsby): Convert pagination to TypeScript (#23717)

* Convert pagination schema type to typescript

* Update getPagination import in schema file

* PR suggested improvements

packages/gatsby/src/schema/schema.js

@@ -28,7 +28,7 @@ const {
   processFieldExtensions,
   internalExtensionNames,
 } = require(`./extensions`)
-const { getPagination } = require(`./types/pagination`)
+import { getPagination } from "./types/pagination"
 const { getSortInput, SORTABLE_ENUM } = require(`./types/sort`)
 const { getFilterInput, SEARCHABLE_ENUM } = require(`./types/filter`)
 const { isGatsbyType, GatsbyGraphQLTypeKind } = require(`./types/type-builders`)

packages/gatsby/src/schema/types/pagination.ts

@@ -0,0 +1,131 @@
+import {
+  SchemaComposer,
+  ObjectTypeComposer,
+  InputTypeComposer,
+  InterfaceTypeComposer,
+  ComposeFieldConfigMap,
+} from "graphql-compose"
+import { getFieldsEnum } from "./sort"
+import { addDerivedType } from "./derived-types"
+import { distinct, group } from "../resolvers"
+
+export const getPageInfo = <TContext = any>({
+  schemaComposer,
+}: {
+  schemaComposer: SchemaComposer<TContext>
+}): ObjectTypeComposer =>
+  schemaComposer.getOrCreateOTC(`PageInfo`, tc => {
+    tc.addFields({
+      currentPage: `Int!`,
+      hasPreviousPage: `Boolean!`,
+      hasNextPage: `Boolean!`,
+      itemCount: `Int!`,
+      pageCount: `Int!`,
+      perPage: `Int`,
+    })
+  })
+
+export const getEdge = <TContext = any>({
+  schemaComposer,
+  typeComposer,
+}: {
+  schemaComposer: SchemaComposer<TContext>
+  typeComposer: ObjectTypeComposer | InterfaceTypeComposer
+}): ObjectTypeComposer => {
+  const typeName = `${typeComposer.getTypeName()}Edge`
+  addDerivedType({ typeComposer, derivedTypeName: typeName })
+  return schemaComposer.getOrCreateOTC(typeName, tc => {
+    tc.addFields({
+      next: typeComposer,
+      node: typeComposer.getTypeNonNull(),
+      previous: typeComposer,
+    })
+  })
+}
+
+const createPagination = <TSource = any, TContext = any>({
+  schemaComposer,
+  typeComposer,
+  fields,
+  typeName,
+}: {
+  schemaComposer: SchemaComposer<TContext>
+  typeComposer: ObjectTypeComposer | InterfaceTypeComposer
+  fields: ComposeFieldConfigMap<TSource, TContext>
+  typeName: string
+}): ObjectTypeComposer => {
+  const paginationTypeComposer: ObjectTypeComposer = schemaComposer.getOrCreateOTC(
+    typeName,
+    tc => {
+      tc.addFields({
+        totalCount: `Int!`,
+        edges: [getEdge({ schemaComposer, typeComposer }).getTypeNonNull()],
+        nodes: [typeComposer.getTypeNonNull()],
+        pageInfo: getPageInfo({ schemaComposer }).getTypeNonNull(),
+        ...fields,
+      })
+    }
+  )
+  paginationTypeComposer.makeFieldNonNull(`edges`)
+  paginationTypeComposer.makeFieldNonNull(`nodes`)
+  addDerivedType({ typeComposer, derivedTypeName: typeName })
+  return paginationTypeComposer
+}
+
+export const getGroup = <TContext = any>({
+  schemaComposer,
+  typeComposer,
+}: {
+  schemaComposer: SchemaComposer<TContext>
+  typeComposer: ObjectTypeComposer | InterfaceTypeComposer
+}): ObjectTypeComposer => {
+  const typeName = `${typeComposer.getTypeName()}GroupConnection`
+  const fields = {
+    field: `String!`,
+    fieldValue: `String`,
+  }
+  return createPagination({ schemaComposer, typeComposer, fields, typeName })
+}
+
+export const getPagination = <TContext = any>({
+  schemaComposer,
+  typeComposer,
+}: {
+  schemaComposer: SchemaComposer<TContext>
+  typeComposer: ObjectTypeComposer | InterfaceTypeComposer
+}): ObjectTypeComposer => {
+  const inputTypeComposer: InputTypeComposer = typeComposer.getInputTypeComposer()
+  const typeName = `${typeComposer.getTypeName()}Connection`
+  const fieldsEnumTC = getFieldsEnum({
+    schemaComposer,
+    typeComposer,
+    inputTypeComposer,
+  })
+  const fields = {
+    distinct: {
+      type: [`String!`],
+      args: {
+        field: fieldsEnumTC.getTypeNonNull(),
+      },
+      resolve: distinct,
+    },
+    group: {
+      type: [getGroup({ schemaComposer, typeComposer }).getTypeNonNull()],
+      args: {
+        skip: `Int`,
+        limit: `Int`,
+        field: fieldsEnumTC.getTypeNonNull(),
+      },
+      resolve: group,
+    },
+  }
+  const paginationTypeComposer: ObjectTypeComposer = createPagination({
+    schemaComposer,
+    typeComposer,
+    fields,
+    typeName,
+  })
+  paginationTypeComposer.makeFieldNonNull(`distinct`)
+  paginationTypeComposer.makeFieldNonNull(`group`)
+  return paginationTypeComposer
+}