Fix(GraphQL): Fix bug with password query rewriting

graphql/e2e/common/query.go

@@ -3051,6 +3051,33 @@ func checkUser(t *testing.T, userObj, expectedObj *user) {
 	}
 }
 
+func checkUserPasswordWithAlias(t *testing.T, userObj, expectedObj *user) {
+	checkUserParams := &GraphQLParams{
+		Query: `query checkUserPassword($name: String!, $pwd: String!) {
+			verify : checkUserPassword(name: $name, password: $pwd) { name }
+		}`,
+		Variables: map[string]interface{}{
+			"name": userObj.Name,
+			"pwd":  userObj.Password,
+		},
+	}
+
+	gqlResponse := checkUserParams.ExecuteAsPost(t, GraphqlURL)
+	RequireNoGQLErrors(t, gqlResponse)
+
+	var result struct {
+		CheckUserPasword *user `json:"verify,omitempty"`
+	}
+
+	err := json.Unmarshal([]byte(gqlResponse.Data), &result)
+	require.Nil(t, err)
+
+	opt := cmpopts.IgnoreFields(user{}, "Password")
+	if diff := cmp.Diff(expectedObj, result.CheckUserPasword, opt); diff != "" {
+		t.Errorf("result mismatch (-want +got):\n%s", diff)
+	}
+}
+
 func passwordTest(t *testing.T) {
 	newUser := &user{
 		Name:     "Test User",
@@ -3095,6 +3122,7 @@ func passwordTest(t *testing.T) {
 			string(gqlResponse.Data))
 
 		checkUser(t, newUser, newUser)
+		checkUserPasswordWithAlias(t, newUser, newUser)
 		checkUser(t, &user{Name: "Test User", Password: "Wrong Pass"}, nil)
 
 		gqlResponse = postExecutor(t, GraphqlURL, updateUserParams)

graphql/resolve/query_rewriter.go

@@ -209,7 +209,7 @@ func passwordQuery(m schema.Query, authRw *authRewriter) (*gql.GraphQuery, error
 	// or dgQuery may be empty and its children may contain check<Type>Password query.
 	// Find the exact dgQuery with the name check<Type>Password query.
 	mainQuery := dgQuery
-	for !strings.HasPrefix(mainQuery.Attr, m.ResponseName()) {
+	for !strings.HasPrefix(mainQuery.Attr, m.Name()) {
 		mainQuery = mainQuery.Children[0]
 	}
 
@@ -412,7 +412,7 @@ func rewriteAsGet(
 	// caught here but in case of interface, we need to check validity on each
 	// implementing type as Rules for the interface are made empty.
 	if rbac == schema.Negative {
-		return &gql.GraphQuery{Attr: query.ResponseName() + "()"}
+		return &gql.GraphQuery{Attr: query.Name() + "()"}
 	}
 
 	// For interface, empty query should be returned if Auth rules are
@@ -427,7 +427,7 @@ func rewriteAsGet(
 		}
 
 		if !implementingTypesHasFailedRules {
-			return &gql.GraphQuery{Attr: query.ResponseName() + "()"}
+			return &gql.GraphQuery{Attr: query.Name() + "()"}
 		}
 	}
 

graphql/resolve/query_test.yaml

@@ -2352,6 +2352,24 @@
       }
     }
 
+-
+  name: "Password query with alias"
+  gqlquery: |
+    query {
+      verify : checkUserPassword(name: "user1", pwd: "Password") {
+        name
+      }
+    }
+  dgquery: |-
+    query {
+      checkUserPassword(func: eq(User.name, "user1")) @filter((eq(val(pwd), 1) AND type(User))) {
+        name : User.name
+        dgraph.uid : uid
+      }
+      checkPwd(func: eq(User.name, "user1")) @filter(type(User)) {
+        pwd as checkpwd(User.pwd, "Password")
+      }
+    }
 
 - name: "Rewrite without custom fields"
   gqlquery: |