How to load a .graphql file using `apollo-server`?

Question

I am currently loading the GraphQL schema using a separate .graphql file, but it is encapsulated within strings:

schema.graphql

const schema = `
  type CourseType {
    _id: String!
    name: String!
  }

  type Query {
    courseType(_id: String): CourseType
    courseTypes: [CourseType]!
  }
`

module.exports = schema

Then using it for the apollo-server:

index.js

const { ApolloServer, makeExecutableSchema } = require('apollo-server')
const typeDefs = require('./schema.graphql')

const resolvers = { ... }

const schema = makeExecutableSchema({
  typeDefs: typeDefs,
  resolvers
})

const server = new ApolloServer({
  schema: schema
})

server.listen().then(({ url }) => {
  console.log(`Server ready at ${url}.`)
})

Is there any way to simply load a .graphql that looks as such? schema.graphql

type CourseType {
  _id: String!
  name: String!
}

type Query {
  courseType(_id: String): CourseType
  courseTypes: [CourseType]!
}

Then it would be parsed in the index.js? I noticed that graphql-yoga supports this, but was wondering if apollo-server does. I cannot find it anywhere in the docs. I can't get fs.readFile to work either.

Answer 1

If you define your type definitions inside a .graphql file, you can read it in one of several ways:

1.) Read the file yourself:

const { readFileSync } = require('fs')

// we must convert the file Buffer to a UTF-8 string
const typeDefs = readFileSync(require.resolve('./type-defs.graphql')).toString('utf-8')

2.) Utilize a library like graphql-tools to do it for you:

const { loadDocuments } = require('@graphql-tools/load');
const { GraphQLFileLoader } = require('@graphql-tools/graphql-file-loader');

// this can also be a glob pattern to match multiple files!
const typeDefs = await loadDocuments('./type-defs.graphql', { 
    file, 
    loaders: [
        new GraphQLFileLoader()
    ]
})

3.) Use a babel plugin or a webpack loader

import typeDefs from './type-defs.graphql'