Firebase - Node Cloud Functions Error parsing triggers: Cannot find module 'firebase-functions'

{
  "name": "functions",
  "description": "Cloud Functions for Firebase",
  "scripts": {
    "serve": "firebase serve --only functions",
    "shell": "firebase functions:shell",
    "start": "npm run shell",
    "deploy": "firebase deploy --only functions",
    "logs": "firebase functions:log"
  },
  "dependencies": {
    "@google-cloud/storage": "^2.0.3",
    "busboy": "^0.2.14",
    "cors": "^2.8.4",
    "firebase-admin": "^6.0.0",
    "firebase-functions": "^2.0.5",
    "request-promise": "^4.2.2",
    "uuid": "^3.3.2"
  },
  "engines": {
    "node": "8"
  },
  "private": true
}

'use strict';
// // Create and Deploy Your First Cloud Functions
// // https://firebase.google.com/docs/functions/write-firebase-functions
//

const functions = require('firebase-functions');
const cors = require('cors')({ origin: true });
const Busboy = require('busboy');
const os = require('os');
const path = require('path');
const fs = require('fs');
const fbAdmin = require('firebase-admin');
const uuid = require('uuid/v4');

// exports.helloWorld = functions.https.onRequest((request, response) => {
//  response.send("Hello from Firebase!");
// });
const gcconfig = {
  projectId: 'rs-0001',
  keyFilename: 'rs-0001.json'
};

const gcs = require('@google-cloud/storage')(gcconfig);

// exports.helloWorld = functions.https.onRequest((request, response) => {
//     response.send("Hello from Firebase!");
//    });

   
fbAdmin.initializeApp({
  credential: fbAdmin.credential.cert(require('./rs-0001.json'))
});

exports.storeImage = functions.https.onRequest((req, res) => {
  return cors(req, res, () => {
    if (req.method !== 'POST') {
      return res.status(500).json({ message: 'Not allowed.' });
    }

    if (
      !req.headers.authorization ||
      !req.headers.authorization.startsWith('Bearer ')
    ) {
      return res.status(401).json({ error: 'Unauthorized.' });
    }

    let idToken;
    idToken = req.headers.authorization.split('Bearer ')[1];

    const busboy = new Busboy({ headers: req.headers });
    let uploadData;
    let oldImagePath;

    busboy.on('file', (fieldname, file, filename, encoding, mimetype) => {
      const filePath = path.join(os.tmpdir(), filename);
      uploadData = { filePath: filePath, type: mimetype, name: filename };
      file.pipe(fs.createWriteStream(filePath));
    });

    busboy.on('field', (fieldname, value) => {
      oldImagePath = decodeURIComponent(value);
    });

    busboy.on('finish', () => {
      const bucket = gcs.bucket('rs-0001.appspot.com');
      const id = uuid();
      let imagePath = 'images/' + id + '-' + uploadData.name;
      if (oldImagePath) {
        imagePath = oldImagePath;
      }

      return fbAdmin
        .auth()
        .verifyIdToken(idToken)
        .then(decodedToken => {
          return bucket.upload(uploadData.filePath, {
            uploadType: 'media',
            destination: imagePath,
            metadata: {
              metadata: {
                contentType: uploadData.type,
                firebaseStorageDownloadTokens: id
              }
            }
          });
        })
        .then(() => {
          return res.status(201).json({
            imageUrl:
              'https://firebasestorage.googleapis.com/v0/b/' +
              bucket.name +
              '/o/' +
              encodeURIComponent(imagePath) +
              '?alt=media&token=' +
              id,
            imagePath: imagePath
          });

          return null
        })
        .catch(error => {
          return res.status(401).json({ error: 'Unauthorized!' });
        });
    });
    return busboy.end(req.rawBody);
  });
});

i  functions: preparing functions directory for uploading...

Error: Error parsing triggers: Cannot find module 'firebase-functions'

Try running "npm install" in your functions directory before deploying.

i  functions: preparing functions directory for uploading...
[2018-10-04T15:34:29.744Z] >>> HTTP REQUEST GET https://runtimeconfig.googleapis.com/v1beta1/projects/rs-0001/configs

[2018-10-04T15:34:31.249Z] <<< HTTP RESPONSE 200 content-type=application/json; charset=UTF-8,vary=X-Origin, Referer, Origin,Accept-Encoding, date=Thu, 04 Oct 2018 15:34:31 GMT, server=ESF, cache-control=private, x-xss-protection=1; mode=block, x-frame-options=SAMEORIGIN, x-content-type-options=nosniff, alt-svc=quic=":443"; ma=2592000; v="44,43,39,35", accept-ranges=none, connection=close

Error: Error parsing triggers: Cannot find module 'firebase-functions'

Try running "npm install" in your functions directory before deploying.