Lesson 1 Error: Type "Query" was defined more than once.

[LeeMellon]

Following along with the first lesson and getting the following error.

Successfully compiled 16 files with Babel.
$ node dist/index.js
(node:87765) UnhandledPromiseRejectionWarning: Error: Type "Query" was defined more than once.
    at Object.buildASTSchema (/Users/iangoodrich/dev/experimental/intro-to-graphql/node_modules/graphql/utilities/buildASTSchema.js:84:15)
    at Object.buildSchemaFromTypeDefinitions (/Users/iangoodrich/dev/experimental/intro-to-graphql/node_modules/graphql-tools/dist/generate/buildSchemaFromTypeDefinitions.js:23:28)
    at Object.makeExecutableSchema (/Users/iangoodrich/dev/experimental/intro-to-graphql/node_modules/graphql-tools/dist/makeExecutableSchema.js:26:29)
    at new ApolloServerBase (/Users/iangoodrich/dev/experimental/intro-to-graphql/node_modules/apollo-server-core/dist/ApolloServer.js:150:43)
    at new ApolloServer (/Users/iangoodrich/dev/experimental/intro-to-graphql/node_modules/apollo-server-express/dist/ApolloServer.js:44:1)
    at new ApolloServer (/Users/iangoodrich/dev/experimental/intro-to-graphql/node_modules/apollo-server/dist/index.js:23:9)
    at start (/Users/iangoodrich/dev/experimental/intro-to-graphql/dist/server.js:47:18)
(node:87765) UnhandledPromiseRejectionWarning: Unhandled promise rejection. This error originated either by throwing inside of an async function without a catch block, or by rejecting a promise which was not handled with .catch(). To terminate the node process on unhandled promise rejection, use the CLI flag `--unhandled-rejections=strict` (see https://nodejs.org/api/cli.html#cli_unhandled_rejections_mode). (rejection id: 1)
(node:87765) [DEP0018] DeprecationWarning: Unhandled promise rejections are deprecated. In the future, promise rejections that are not handled will terminate the Node.js process with a non-zero exit code.

[LeeMellon]

src/server.js

import { ApolloServer } from 'apollo-server'
import { loadTypeSchema } from './utils/schema'
import { authenticate } from './utils/auth'
import { merge } from 'lodash'
import config from './config'
import { connect } from './db'
import product from './types/product/product.resolvers'
import coupon from './types/coupon/coupon.resolvers'
import user from './types/user/user.resolvers'

const types = ['product', 'coupon', 'user']

export const start = async () => {
  const rootSchema = 
    type Cat {
    name: String
    age: Int
    }
    
    type Query {
      myCat: Cat
    }
    
    schema {
      query: Query
      mutation: Mutation
    }
  
  const schemaTypes = await Promise.all(types.map(loadTypeSchema))

  const server = new ApolloServer({
    typeDefs: [rootSchema, ...schemaTypes],
    resolvers: merge({
      Query: {
        myCat() {
          return {name: 'Zangief'}
        }
      }
    }, product, coupon, user),
    async context({ req }) {
      const user = await authenticate(req)
      return { user }
    }
  })

  await connect(config.dbUrl)
  const { url } = await server.listen({ port: config.port })

  console.log(`GQL server ready at ${url}`)
}

[laniehei]

Hi @LeeMellon, does the solution code to this exercise help at all? https://github.com/FrontendMasters/intro-to-graphql/blob/lesson-1-solution/src/server.js

[bilalds]

Going through the same lesson and also seeing this issue. There are slight differences in the code the instructor has in the first lesson vs the repo when you clone it.

[bilalds]

(node:14474) UnhandledPromiseRejectionWarning: Error: There can be only one type named "Query".

[bilalds]

Okay, my issue was resolved with installing bcrypt and running the mongodb server.

[enigmatikme]

same issue

[leventefrks]

Yes, there are slight differences between the code in the video and the repo. I spent some time to figure it out but I finally managed to solve it by modifying the db.js file and putting an _ before the word Query in the server.js

db.js:

export const connect = (url = options.dbUrl, opts = {}) => {
return mongoose
.connect(url, {
useNewUrlParser: true,
useCreateIndex: true,
useUnifiedTopology: true
})
.then(() => console.log('Database Connected'))
.catch(err => console.log(err))
}

server.js:

export const start = async () => {
const rootSchema = `
type Cat {
name: String
}

type _Query {
  myCat: Cat
}

schema {
  query: _Query
  mutation: Mutation
}

`
const schemaTypes = await Promise.all(types.map(loadTypeSchema))

const server = new ApolloServer({
typeDefs: [rootSchema, ...schemaTypes],
resolvers: merge(
{
_Query: {
myCat() {
return { name: 'Garfield' }
}
}
},
product,
coupon,
user
),
async context({ req }) {
const user = await authenticate(req)
return { user }
}
})