Cloud functions onCreate Trigger function failing HTTP Error: 400, The request has errors

Question

When I try to add trigger for Firestore OnCreate the deployment fails for HTTP Error: 400, The request has errors.

Basically I want to write to a new doc if the record is created in different collection. but get the userId. this involves 2 write and 1 read. not sure if it is efficient way

But the log and the error has no detail on what the error is

Here's my code

'use strict';

import * as functions from 'firebase-functions';
import * as admin from 'firebase-admin';

const requestPromise = require('request-promise');

admin.initializeApp();
const firestore = admin.firestore();
const cors = require('cors')({
    origin: true,
});


exports.joinCommunity = functions.region('europe-west2').firestore.document('users/{userId}/community')
    .onCreate((snap, context) => {
        const data = snap.data();
        const communityRef = firestore.doc(`community/${data['cid']}`);
        const user = {
            uid: context.params.userId,
            joined_on: context.timestamp
        }
        return communityRef.collection('members').doc(context.params.userId).set(user, { merge: true });
    });

Appreciate the support or pointer

Solution: The problem was that I had used the Collection path instead of the document path. Changing the .document(users/{userId}/community') to .document('users/{userId}/community/{communityId}') fixed the error

Additionally: Also note in my code i have used Javascript way of export in typescript. Not an issue but the right way yo use it export const joinCommunity

If you're having problems deploying, and the error is not helpful, contact Firebase support for assistance. support.google.com/firebase/contact/support — Doug Stevenson

Renaud Tarnec Renaud Tarnec · Accepted Answer · 2020-06-26T06:29:10

To define a Cloud Firestore trigger, you need to specify a document path. With users/{userId}/community you are specifying a collection path.

So either you trigger your CF when a document is created in the users collection (with users/{userId}) or in the community subcollection (with users/{userId}/community/{docId}).

Have also a look at the following GitHub page https://github.com/firebase/functions-samples/tree/master/typescript-getting-started and in particular at the different ways (between JavaScript and TypeScript) for importing the Cloud Functions SDK and Admin SDK modules and for exporting the Cloud Functions.

Cloud functions onCreate Trigger function failing HTTP Error: 400, The request has errors

1 Answers