'functions' is assigned a value but never used - firebase

Question

I am getting an error in terminal when trying to run 'firebase deploy'. This brings the error
1:7 error 'functions' is assigned a value but never used no-unused-vars
here is my index.js file
// The Cloud Functions for Firebase SDK to create Cloud Functions and setup triggers.
const functions = require('firebase-functions');
// The Firebase Admin SDK to access Firestore.
const admin = require('firebase-admin');
admin.initializeApp();
// Take the text parameter passed to this HTTP endpoint and insert it into
// Firestore under the path /messages/:documentId/original
exports.addMessage = functions.https.onRequest(async (req, res) => {
// Grab the text parameter.
const original = req.query.text;
// Push the new message into Firestore using the Firebase Admin SDK.
const writeResult = await admin.firestore().collection('messages').add({original: original});
// Send back a message that we've successfully written the message
res.json({result: `Message with ID: ${writeResult.id} added.`});
});
// Listens for new messages added to /messages/:documentId/original and creates an
// uppercase version of the message to /messages/:documentId/uppercase
exports.makeUppercase = functions.firestore.document('/messages/{documentId}')
.onCreate((snap, context) => {
// Grab the current value of what was written to Firestore.
const original = snap.data().original;
// Access the parameter `{documentId}` with `context.params`
functions.logger.log('Uppercasing', context.params.documentId, original);
const uppercase = original.toUpperCase();
// You must return a Promise when performing asynchronous tasks inside a Functions such as
// writing to Firestore.
// Setting an 'uppercase' field in Firestore document returns a Promise.
return snap.ref.set({uppercase}, {merge: true});
});
this is directly from the firebase functions documentation

Answer 1

Your index file is outside the functions folder.

Answer 2

In my case i just added warning instead of error in the rules at the
.eslintrc.js file
rules: {
"no-unused-vars": "warn"
},

Answer 3

You can also wrap any block of code with eslint specific comments to disable a rule for that block:
/* eslint-disable no-unused-vars */
(....Your Code....)
/* eslint-enable no-unused-vars */
this way you need not to comment your pre-deploy script checks
and you can disable the enlint properties for the selected block

Answer 4

In firebase.json, delete these 3 lines :
"predeploy": [
"npm --prefix \"$RESOURCE_DIR\" run lint"
]
In functions folder/package.json, delete these lines :
"devDependencies": {
"eslint": "^8.9.0", // delete
"eslint-config-google": "^0.14.0", // delete
}
"scripts": {
"lint": "eslint .", // delete
},
Delete node_modules in function folder then reinstall all with npm install (you must be in the function folder)
Then : firebase deploy will work fine