Apollo Server Express v4 GraphQL this.findOneById is not a function - mongodb

Question

I have the following ApolloServer (v4)
import { MongoDataSource } from 'apollo-datasource-mongodb'
export default class LoaderAsset extends MongoDataSource {
async getAsset(assetId) {
return this.findOneById(assetId) // ERROR IS HERE
}
}
async function startApolloServer(app) {
const httpServer = http.createServer(app);
const server = new ApolloServer({
typeDefs,
resolvers,
plugins: [ApolloServerPluginDrainHttpServer({ httpServer })]
});
await server.start();
app.use(
'/graphql',
cors(),
bodyParser.json(),
expressMiddleware(server, {
context: async ({ req }) => {
return {
dataSources: {
loaderAsset: new LoaderAsset(modelAsset),
}
}
},
}),
);
const port = config.get('Port') || 8081;
await new Promise(resolve => httpServer.listen({ port }, resolve));
}
when I run graphql and send one assetId, everything is working till I get following error:
this.findOneById is not a function
By the way (this) has collection and model objects but not any methods.
is it because apollo-datasource-mongodb is not compatible with the new version of apollo server v4?
dataSources in v3 were as follows:
dataSources: () => ({
users: new Users(client.db().collection('users'))
// OR
// users: new Users(UserModel)
})
but in the new version dataSources is inside the context
Maybe the issue is because of this change.

Answer 1

Credit to: https://github.com/systemkrash on https://github.com/GraphQLGuide/apollo-datasource-mongodb/issues/114
what i did is i override my datasource class so I can call the initialize method inside in the MongoDatasource class. Now it works for me.
import { MongoDataSource } from 'apollo-datasource-mongodb';
class ReceptionDataSource extends MongoDataSource {
constructor({ collection, cache }) {
super(collection);
super.initialize({ context: this.context, cache });
}
async getReception(receptionId) {
return await this.findOneById(receptionId);
}
}
export default ReceptionDataSource;
then in my context
async function startApolloServer(app) {
const httpServer = http.createServer(app);
const server = new ApolloServer({
typeDefs,
resolvers,
plugins: [ApolloServerPluginDrainHttpServer({ httpServer })]
});
await server.start();
app.use(
'/graphql',
cors(),
bodyParser.json(),
expressMiddleware(server, {
context: async ({ req }) => {
const { cache } = server
return {
dataSources: {
loaderAsset: new ReceptionDataSource({collection: ReceptionModel, cache}),
}
}
},
}),
);
const port = config.get('Port') || 8081;
await new Promise(resolve => httpServer.listen({ port }, resolve));
}