freeCodeCamp/tools/scripts/seed/seedChallenges.js

const path = require('path');
const fs = require('fs');
require('dotenv').config({ path: path.resolve(__dirname, '../../../.env') });
const { MongoClient, ObjectID } = require('mongodb');
const { flatten } = require('lodash');
const debug = require('debug');

const { getChallengesForLang } = require('../../../curriculum/getChallenges');
const { createPathMigrationMap } = require('./createPathMigrationMap');

const log = debug('fcc:tools:seedChallenges');
const { MONGOHQ_URL, LOCALE: lang = 'english' } = process.env;

function handleError(err, client) {
  if (err) {
    console.error('Oh noes!!');
    console.error(err);
    try {
      client.close();
    } catch (e) {
      // no-op
    } finally {
      /* eslint-disable-next-line no-process-exit */
      process.exit(1);
    }
  }
}

MongoClient.connect(MONGOHQ_URL, { useNewUrlParser: true }, function(
  err,
  client
) {
  handleError(err, client);

  log('Connected successfully to mongo at %s', MONGOHQ_URL);

  const db = client.db('freecodecamp');
  const challengeCollection = db.collection('challenge');

  challengeCollection.deleteMany({}, async err => {
    handleError(err, client);

    log('deleted all the challenges');

    const curriculum = await getChallengesForLang(lang);

    const allChallenges = Object.keys(curriculum)
      .map(key => curriculum[key].blocks)
      .reduce((challengeArray, superBlock) => {
        const challengesForBlock = Object.keys(superBlock).map(
          key => superBlock[key].challenges
        );
        return [...challengeArray, ...flatten(challengesForBlock)];
      }, [])
      .map(challenge => {
        const currentId = challenge.id.slice(0);
        challenge._id = ObjectID(currentId);
        delete challenge.id;
        return challenge;
      });

    try {
      challengeCollection.insertMany(allChallenges, { ordered: false }, err => {
        handleError(err, client);
        log('challenge seed complete');
        client.close();
      });
    } catch (e) {
      handleError(e, client);
    } finally {
      log('generating path migration map');
      const pathMap = createPathMigrationMap(curriculum);
      const outputDir = path.resolve(
        __dirname,
        '../../../api-server/server/resources/pathMigration.json'
      );
      fs.writeFile(outputDir, JSON.stringify(pathMap), err => {
        if (err) {
          console.error('Oh noes!!');
          console.error(err);
        }
        log('path migration map generated');
      });
    }
  });
});