`__typename` returned by the server isn't match to graphql schema

When I build schema using type-graphql and make a server with apollo-server-lambda and deploy it to netlify functions, something wrong happened.

schema generated by type-graphql

# -----------------------------------------------
# !!! THIS FILE WAS GENERATED BY TYPE-GRAPHQL !!!
# !!!   DO NOT MODIFY THIS FILE BY YOURSELF   !!!
# -----------------------------------------------

type Project {
  name: String!
  summary: String!
  titleAndSummary: String!
}

type Query {
  projects: [Project!]!
}

Problem

I think when I query to API

{
  __schema {
    types {
      name
    }
  }
}

API must respond like

{
    "data": {
        "__schema": {
            "types": [
                {
                    "name": "Query"
                },
                {
                    "name": "Project"
                },
                // ...
            ]
        }
    }
}

But I got

{
    "data": {
        "__schema": {
            "types": [
                {
                    "name": "Query"
                },
                {
                    "name": "a"
                },
                // ...
            ]
        }
    }
}

I'm going to use graphql with Elm-Graphql what auto-generate modules using their __typename property. That's why I must fix the above problem.

I try hard to resolve it but even can't find where's the problem. It seems like in type-graphql or apollo-server or even netlify functions (I tried both netlify dev server and real server with actual deployment)

Codes

graphql.ts

import 'reflect-metadata';
import { ApolloServer } from 'apollo-server-lambda';
import { buildSchemaSync } from 'type-graphql';
import { QueryResolver, ProjectResolver } from './resolver';

const schema = buildSchemaSync({
  resolvers: [QueryResolver, ProjectResolver],
});

const server = new ApolloServer({
  schema,
  debug: false,
});

export const handler = server.createHandler();

types.ts

import { ObjectType, Field } from 'type-graphql';

@ObjectType()
export class Query {
  @Field((type) => [Project!]!)
  projects!: Project[];
}

@ObjectType()
export class Project {
  @Field((type) => String!)
  name!: string;

  @Field((type) => String!)
  summary!: string;
}

resolver.ts

import { Resolver, Query, FieldResolver, Root } from 'type-graphql';
import { Project } from './types';
import { projectList } from '../../db/fakeDB';

@Resolver()
export class QueryResolver {
  @Query((returns) => [Project])
  projects() {
    return projectList;
  }
}

@Resolver((of) => Project)
export class ProjectResolver {
  @FieldResolver((returns) => String!)
  titleAndSummary(@Root() project: Project) {
    return project.name + ' ++ ' + project.summary;
  }
}

Trial

add __typename to Objec Type directly like below

 @Resolver((of) => Project)
export class ProjectResolver {
  @FieldResolver((returns) => String!)
  titleAndSummary(@Root() project: Project) {
    return project.name + ' ++ ' + project.summary;
  }

  @FieldResolver((returns) => String!)
  __typename() {
    return 'Project';
  }
}

But It throws an error on the request

◈ Error during invocation:  {
  errorMessage: 'Name "__typename" must not begin with "__", which is reserved by GraphQL introspection.',
  errorType: 'Error',
...

How can I solve it?

Because I'm not good at English, I worry about If there's a wrong thing. please let me know and correct. Thanks.

Looks like you have turned on bundle minification, so all the class names are mangled.