feat [CX-2605]: Add the list of the artists in My Collection to myCol…

…lectionInfo (#4127)

* expose my collection artists endpoint

* add totalCount

* add tests

* update description and use paginationResolver

* add size and page to `pageable`

* use `page` instead of `offset` for pagination

* chore

* refactor promise chaining to async/await

_schemaV2.graphql

@@ -10482,6 +10482,16 @@ enum MyCollectionArtworkSorts {
 type MyCollectionConnection {
   artistsCount: Int!
   artworksCount: Int!
+
+  # A connection of artists in the users' collection
+  collectedArtistsConnection(
+    after: String
+    before: String
+    first: Int
+    last: Int
+    page: Int
+    size: Int
+  ): ArtistConnection
   default: Boolean!
   description: String!
 
@@ -10554,6 +10564,16 @@ type MyCollectionEdge {
 type MyCollectionInfo {
   artistsCount: Int!
   artworksCount: Int!
+
+  # A connection of artists in the users' collection
+  collectedArtistsConnection(
+    after: String
+    before: String
+    first: Int
+    last: Int
+    page: Int
+    size: Int
+  ): ArtistConnection
   default: Boolean!
   description: String!
   includesPurchasedArtworks: Boolean!

src/schema/v2/me/__tests__/myCollectionInfo.test.ts

@@ -39,4 +39,101 @@ describe("me.myCollectionInfo", () => {
       }
     `)
   })
+
+  describe("collectedArtistsConnection", () => {
+    it("returns a connection for the artists in the users' collection", async () => {
+      const query = gql`
+        {
+          me {
+            myCollectionInfo {
+              collectedArtistsConnection(first: 5) {
+                totalCount
+                edges {
+                  node {
+                    name
+                  }
+                }
+              }
+            }
+          }
+        }
+      `
+
+      const context: Partial<ResolverContext> = {
+        collectionLoader: async () => ({}),
+        meLoader: async () => ({
+          id: "some-user-id",
+        }),
+        collectionArtistsLoader: async () => ({
+          headers: { "x-total-count": "3" },
+          body: [
+            {
+              name: "Artist 1",
+            },
+            {
+              name: "Artist 2",
+            },
+            {
+              name: "Artist 3",
+            },
+          ],
+        }),
+      }
+
+      const data = await runAuthenticatedQuery(query, context)
+
+      expect(data).toEqual(collectedArtistsConnectionData)
+
+      expect(data.me.myCollectionInfo.collectedArtistsConnection)
+        .toMatchInlineSnapshot(`
+        Object {
+          "edges": Array [
+            Object {
+              "node": Object {
+                "name": "Artist 1",
+              },
+            },
+            Object {
+              "node": Object {
+                "name": "Artist 2",
+              },
+            },
+            Object {
+              "node": Object {
+                "name": "Artist 3",
+              },
+            },
+          ],
+          "totalCount": 3,
+        }
+      `)
+    })
+  })
 })
+
+const collectedArtistsConnectionData = {
+  me: {
+    myCollectionInfo: {
+      collectedArtistsConnection: {
+        totalCount: 3,
+        edges: [
+          {
+            node: {
+              name: "Artist 1",
+            },
+          },
+          {
+            node: {
+              name: "Artist 2",
+            },
+          },
+          {
+            node: {
+              name: "Artist 3",
+            },
+          },
+        ],
+      },
+    },
+  },
+}

src/schema/v2/me/myCollectionInfo.ts

@@ -6,7 +6,11 @@ import {
   GraphQLFieldConfig,
   GraphQLInt,
 } from "graphql"
+import { convertConnectionArgsToGravityArgs } from "lib/helpers"
+import { pageable } from "relay-cursor-paging"
+import { artistConnection } from "schema/v2/artist"
 import { ResolverContext } from "types/graphql"
+import { paginationResolver } from "../fields/pagination"
 
 export const myCollectionInfoFields = {
   description: {
@@ -33,6 +37,30 @@ export const myCollectionInfoFields = {
     type: new GraphQLNonNull(GraphQLInt),
     resolve: ({ artists_count }) => artists_count,
   },
+  collectedArtistsConnection: {
+    description: "A connection of artists in the users' collection",
+    type: artistConnection.connectionType,
+    args: pageable({
+      page: { type: GraphQLInt },
+      size: { type: GraphQLInt },
+    }),
+    resolve: async (_root, args, context) => {
+      const { collectionArtistsLoader } = context
+
+      if (!collectionArtistsLoader) return
+
+      const { page, offset, size } = convertConnectionArgsToGravityArgs(args)
+
+      const { body, headers } = await collectionArtistsLoader("my-collection", {
+        size,
+        page,
+        total_count: true,
+      })
+      const totalCount = parseInt(headers["x-total-count"] || "0", 10)
+
+      return paginationResolver({ totalCount, offset, size, page, body, args })
+    },
+  },
 }
 
 const MyCollectionInfoType = new GraphQLObjectType<any, ResolverContext>({