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

Back in the day I wrote a teeny-tiny .graphql loader myself. It is very small, very simple, and the only thing you have to do is import it before you try to import any .graphql files. I have used it ever since even though I am sure that there are some 3rd party loaders available. Here’s the code:

// graphql-loader.js

const oldJSHook = require.extensions[".js"];

const loader = (module, filename) => {
  const oldJSCompile = module._compile;
  module._compile = function (code, file) {
    code = `module.exports = `r${code}`;`;
    module._compile = oldJSCompile;
    module._compile(code, file);
  };
  oldJSHook(module, filename);
};

require.extensions[".graphql"] = loader;
require.extensions[".gql"] = loader;

And then in your app:

// index.js

import "./graphql-loader"; // (or require("./graphql-loader") if you prefer)

That’s it, you can then import typeDefs from "./type-defs.graphql" wherever you want.

The loader works by wrapping the text in your .graphql file inside a template string and compiling it as a simple JS module:

module.exports = ` ...your gql schema... `;

This worked for me:

const { gql } = require('apollo-server');
const fs = require('fs');
const path = require('path');

//function that imports .graphql files
const importGraphQL = (file) =>{
  return fs.readFileSync(path.join(__dirname, file),"utf-8");
}

const gqlWrapper = (...files)=>{
  return gql`${files}`;
}


const enums = importGraphQL('./enums.graphql');
const schema = importGraphQL('./schema.graphql');

module.exports = gqlWrapper(enums,schema);

Figured it out using fs (thanks to Tal Z):

index.js

const fs = require('fs')
const mongoUtil = require('./mongoUtil')
const { ApolloServer, makeExecutableSchema } = require('apollo-server')

function readContent (file, callback) {
  fs.readFile(file, 'utf8', (err, content) => {
    if (err) return callback(err)
    callback(null, content)
  })
}

mongoUtil.connectToServer((error) => {
  if (error) {
    console.error('Error connecting to MongoDB.', error.stack)
    process.exit(1)
  }

  console.log('Connected to database.')

  const Query = require('./resolvers/Query')

  const resolvers = {
    Query
  }

  readContent('./schema.graphql', (error, content) => {
    if (error) throw error

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

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

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

schema.graphql

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

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

I use this helper:

import { readFileSync } from "fs";
const requireGQL = (file) =>
  gql`${readFileSync(require.resolve(file)).toString("utf-8")}`;

Throw that at the top of your file and you can just:

const client = new ApolloClient({ uri: 'https://myendpoint.com/graphql' });
const { data } = await client.query({ query: requireGQL("./myquery.gql") });

For anyone who is looking for the Apollo documentation for this question here it is: https://www.apollographql.com/docs/apollo-server/workflow/generate-types

It describes using readFileSync like many answers here, but I was having trouble finding where they actually describe this method. Here’s the snippet as well:

// ...other imports

import { readFileSync } from 'fs';


// Note: this uses a path relative to the project's

// root directory, which is the current working directory

// if the server is executed using `npm run`.

const typeDefs = readFileSync('./schema.graphql', { encoding: 'utf-8' });


const server = new ApolloServer<MyContext>({

  typeDefs,

  resolvers,

});


// ... start our server