feat(GraphQL): Unions

graphql/e2e/common/common.go

@@ -392,6 +392,7 @@ func RunAll(t *testing.T) {
 	t.Run("fragment in mutation", fragmentInMutation)
 	t.Run("fragment in query", fragmentInQuery)
 	t.Run("fragment in query on Interface", fragmentInQueryOnInterface)
+	t.Run("fragment in query on union", fragmentInQueryOnUnion)
 	t.Run("fragment in query on Object", fragmentInQueryOnObject)
 
 	// lambda tests

graphql/e2e/common/fragment.go

@@ -21,6 +21,8 @@ import (
 	"fmt"
 	"testing"
 
+	"github.com/dgraph-io/dgraph/testutil"
+
 	"github.com/google/go-cmp/cmp"
 	"github.com/google/go-cmp/cmp/cmpopts"
 	"github.com/stretchr/testify/require"
@@ -383,6 +385,121 @@ func fragmentInQueryOnInterface(t *testing.T) {
 	deleteThingTwo(t, thingTwoId)
 }
 
+func fragmentInQueryOnUnion(t *testing.T) {
+	newStarship := addStarship(t)
+	humanID := addHuman(t, newStarship.ID)
+	homeId, dogId, parrotId, plantId := addHome(t, humanID)
+
+	queryHomeParams := &GraphQLParams{
+		Query: `query {
+			queryHome {
+				members {
+					__typename
+					... on Animal {
+						category
+					}
+					... on Dog {
+						id
+						breed
+					}
+					... on Parrot {
+						repeatsWords
+					}
+					... on Employee {
+						ename
+					}
+					... on Character {
+						id
+					}
+					... on Human {
+						name
+					}
+					... on Plant {
+						id
+					}
+				}
+			}
+			qh: queryHome {
+				members {
+					... on Animal {
+						__typename
+					}
+					... on Dog {
+						breed
+					}
+					... on Human {
+						name
+					}
+					... on Plant {
+						breed
+					}
+				}
+			}
+		}
+		`,
+	}
+
+	gqlResponse := queryHomeParams.ExecuteAsPost(t, GraphqlURL)
+	RequireNoGQLErrors(t, gqlResponse)
+
+	queryHomeExpected := fmt.Sprintf(`
+	{
+	  "queryHome": [
+		{
+		  "members": [
+			{
+			  "__typename": "Human",
+			  "ename": "Han_employee",
+			  "id": "%s",
+			  "name": "Han"
+			},
+			{
+			  "__typename": "Dog",
+			  "category": "Mammal",
+			  "id": "%s",
+			  "breed": "German Shephard"
+			},
+			{
+			  "__typename": "Parrot",
+			  "category": "Bird",
+			  "repeatsWords": [
+				"Good Morning!",
+				"squawk"
+			  ]
+			},
+			{
+			  "__typename": "Plant",
+			  "id": "%s"
+			}
+		  ]
+		}
+	  ],
+	  "qh": [
+		{
+		  "members": [
+			{
+			  "name": "Han"
+			},
+			{
+			  "__typename": "Dog",
+			  "breed": "German Shephard"
+			},
+			{
+			  "__typename": "Parrot"
+			},
+			{
+			  "breed": "Flower"
+			}
+		  ]
+		}
+	  ]
+	}`, humanID, dogId, plantId)
+	testutil.CompareJSON(t, queryHomeExpected, string(gqlResponse.Data))
+
+	cleanupStarwars(t, newStarship.ID, humanID, "")
+	deleteHome(t, homeId, dogId, parrotId, plantId)
+}
+
 func fragmentInQueryOnObject(t *testing.T) {
 	newStarship := addStarship(t)
 	humanID := addHuman(t, newStarship.ID)

graphql/e2e/common/mutation.go

@@ -2376,7 +2376,7 @@ func addDroid(t *testing.T) string {
 }
 
 func addThingOne(t *testing.T) string {
-	addDroidParams := &GraphQLParams{
+	addThingOneParams := &GraphQLParams{
 		Query: `mutation addThingOne($input: AddThingOneInput!) {
 			addThingOne(input: [$input]) {
 				thingOne {
@@ -2391,7 +2391,7 @@ func addThingOne(t *testing.T) string {
 		}},
 	}
 
-	gqlResponse := addDroidParams.ExecuteAsPost(t, GraphqlURL)
+	gqlResponse := addThingOneParams.ExecuteAsPost(t, GraphqlURL)
 	RequireNoGQLErrors(t, gqlResponse)
 
 	var result struct {
@@ -2409,7 +2409,7 @@ func addThingOne(t *testing.T) string {
 }
 
 func addThingTwo(t *testing.T) string {
-	addDroidParams := &GraphQLParams{
+	addThingTwoParams := &GraphQLParams{
 		Query: `mutation addThingTwo($input: AddThingTwoInput!) {
 			addThingTwo(input: [$input]) {
 				thingTwo {
@@ -2424,7 +2424,7 @@ func addThingTwo(t *testing.T) string {
 		}},
 	}
 
-	gqlResponse := addDroidParams.ExecuteAsPost(t, GraphqlURL)
+	gqlResponse := addThingTwoParams.ExecuteAsPost(t, GraphqlURL)
 	RequireNoGQLErrors(t, gqlResponse)
 
 	var result struct {
@@ -2441,6 +2441,111 @@ func addThingTwo(t *testing.T) string {
 	return result.AddThingTwo.ThingTwo[0].ID
 }
 
+func addHome(t *testing.T, humanId string) (string, string, string, string) {
+	addHomeParams := &GraphQLParams{
+		Query: `mutation addHome($input: AddHomeInput!) {
+			addHome(input: [$input]) {
+				home {
+					id
+					members {
+						__typename
+						... on Animal {
+							id
+						}
+						... on Human {
+							id
+						}
+						... on Plant {
+							id
+						}
+					}
+				}
+			}
+		}`,
+		Variables: map[string]interface{}{
+			"input": map[string]interface{}{
+				"address": "Avenger Street",
+				"members": []interface{}{
+					map[string]interface{}{
+						"dogRef": map[string]interface{}{
+							"category": "Mammal",
+							"breed":    "German Shephard",
+						},
+					},
+					map[string]interface{}{
+						"parrotRef": map[string]interface{}{
+							"category": "Bird",
+							"repeatsWords": []interface{}{
+								"squawk",
+								"Good Morning!",
+							},
+						},
+					},
+					map[string]interface{}{
+						"humanRef": map[string]interface{}{
+							"id": humanId,
+						},
+					},
+					map[string]interface{}{
+						"plantRef": map[string]interface{}{
+							"breed": "Flower",
+						},
+					},
+				},
+				"favouriteMember": map[string]interface{}{
+					"humanRef": map[string]interface{}{
+						"id": humanId,
+					},
+				},
+			},
+		},
+	}
+
+	gqlResponse := addHomeParams.ExecuteAsPost(t, GraphqlURL)
+	RequireNoGQLErrors(t, gqlResponse)
+
+	var result struct {
+		AddHome struct {
+			Home []struct {
+				ID      string
+				Members []struct {
+					Typename string `json:"__typename"`
+					ID       string
+				}
+			}
+		}
+	}
+	err := json.Unmarshal([]byte(gqlResponse.Data), &result)
+	require.NoError(t, err)
+
+	homeId := result.AddHome.Home[0].ID
+	requireUID(t, homeId)
+
+	var dogId, parrotId, plantId string
+	for _, member := range result.AddHome.Home[0].Members {
+		switch member.Typename {
+		case "Dog":
+			dogId = member.ID
+		case "Parrot":
+			parrotId = member.ID
+		case "Plant":
+			plantId = member.ID
+		}
+	}
+	return homeId, dogId, parrotId, plantId
+}
+
+func deleteHome(t *testing.T, homeId, dogId, parrotId, plantId string) {
+	homeFilter := map[string]interface{}{"id": []string{homeId}}
+	deleteGqlType(t, "Home", homeFilter, 1, nil)
+	dogFilter := map[string]interface{}{"id": []string{dogId}}
+	deleteGqlType(t, "Dog", dogFilter, 1, nil)
+	parrotFilter := map[string]interface{}{"id": []string{parrotId}}
+	deleteGqlType(t, "Parrot", parrotFilter, 1, nil)
+	plantFilter := map[string]interface{}{"id": []string{plantId}}
+	deleteGqlType(t, "Plant", plantFilter, 1, nil)
+}
+
 func deleteThingOne(t *testing.T, thingOneId string) {
 	thingOneFilter := map[string]interface{}{"id": []string{thingOneId}}
 	deleteGqlType(t, "ThingOne", thingOneFilter, 1, nil)

graphql/e2e/directives/schema.graphql

@@ -194,6 +194,58 @@ type Person1 {
     friends: [Person1] @hasInverse(field: friends)
 }
 
+# union testing - start
+enum AnimalCategory {
+	Fish
+	Amphibian
+	Reptile
+	Bird
+	Mammal
+	InVertebrate
+}
+
+interface Animal {
+	id: ID!
+	category: AnimalCategory @search
+}
+
+type Dog implements Animal {
+	breed: String @search
+}
+
+type Parrot implements Animal {
+	repeatsWords: [String]
+}
+
+type Cheetah implements Animal {
+	speed: Float
+}
+
+"""
+This type specifically doesn't implement any interface.
+We need this to test out all cases with union.
+"""
+type Plant {
+	id: ID!
+	breed: String # field with same name as a field in type Dog
+}
+
+union HomeMember = Dog | Parrot | Human | Plant
+
+type Zoo {
+	id: ID!
+	animals: [Animal]
+	city: String
+}
+
+type Home {
+	id: ID!
+	address: String
+	members: [HomeMember]
+	favouriteMember: HomeMember
+}
+# union testing - end
+
 type Query {
 	authorsByName(name: String!): [Author] @lambda
 }