Getting node "Error: Cannot find module 'core-js/proposals/array-flat-and-flat-map'" while running apollo-server

Question

apollo-server-Getting started

I am doing apollo-server setup in my system using above link. when i tried to run node file using node index.js. I am getting below error:

internal/modules/cjs/loader.js:611
    throw err;
    ^
Error: Cannot find module 'core-js/proposals/array-flat-and-flat-map'
    at Function.Module._resolveFilename 
(internal/modules/cjs/loader.js:609:15)
    at Function.Module._load (internal/modules/cjs/`loader.js:535:25`)
    at Module.require (internal/modules/cjs/`loader.js:663:17`)
    at require (internal/modules/cjs/`helpers.js:20:18`)
    at Object.<anonymous> (E:\`GraphQLApolloServer`\node_modules\`apollo-
env`\lib\`polyfills`\`array.js:3:1`)
    at Module._compile (internal/modules/cjs/`loader.js:734:30`)
    at Object.Module._extensions..`js` (internal/modules/cjs/`loader.js:745:10`)
    at Module.load (internal/modules/cjs/`loader.js:626:32`)
    at tryModuleLoad (internal/modules/cjs/`loader.js:566:12`)
    at Function.Module._load (internal/modules/cjs/loader.js:558:3)`

Any idea how to resolve this error?

I tried different ways like re-installing node and upgraded to latest version but didn't get any success.

• create a node project using npm init --yes
• npm install --save apollo-server graphql
• copy index.js from https://www.apollographql.com/docs/apollo-server/getting-started.html
• node index.js

Answer 1

package.json

{
  "name": "backend",
  "version": "1.0.0",
  "description": "",
  "main": "index.js",
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1"
  },
  "keywords": [],
  "author": "",
  "license": "ISC",
  "dependencies": {
    "apollo-server": "^2.3.3",
    "core-js": "3.0.0-beta.11",
    "graphql": "^14.1.1"
  }
}

Answer 2

My project broke in the same way when upgrading apollo-server-express from 2.3.1 to 2.3.3.

Try installing apollo-server version 2.3.1

I needed to also reset my package-lock. (And I removed my node_modules dir.) Guess the problem is in a dependent package. But I'm not digging any deeper as of now.

Running fine with latest graphql package. (14.1.1)

So try setting up your project with the following:

npm install --save apollo-server**@2.3.1** graphql