Firestore triggers for Firebase Cloud Functions not working - firebase

Question

Goal
My goal is to print the output of any created/updated/deleted documents in Cloud Firestore using Cloud Functions
Setup
I'm currently using the Firebase emulator for testing purposes. The Admin SDK is able to successfully connect to the Firestore database, but triggers won't be called. Here is my firebase.json for my project:
{
"firestore": {
"rules": "firestore.rules",
"indexes": "firestore.indexes.json"
},
"emulators": {
"auth": {
"port": 9099,
"host": "127.0.0.1"
},
"firestore": {
"port": 8080,
"host": "127.0.0.1"
},
"ui": {
"enabled": true
}
},
"functions": {
"source": "functions",
"predeploy": [
"npm --prefix \"$RESOURCE_DIR\" run lint"
]
}
}
All triggers are being loaded according to the—
Logs which reveal the following setup:
Emulator UI logging to ui-debug.log
auth function initialized.
auth function initialized.
firestore function initialized.
┌─────────────────────────────────────────────────────────────┐
│ ✔ All emulators ready! It is now safe to connect your app. │
│ i View Emulator UI at http://localhost:4000 │
└─────────────────────────────────────────────────────────────┘
┌────────────────┬────────────────┬─────────────────────────────────┐
│ Emulator │ Host:Port │ View in Emulator UI │
├────────────────┼────────────────┼─────────────────────────────────┤
│ Authentication │ 127.0.0.1:9099 │ http://localhost:4000/auth │
├────────────────┼────────────────┼─────────────────────────────────┤
│ Functions │ localhost:5001 │ http://localhost:4000/functions │
├────────────────┼────────────────┼─────────────────────────────────┤
│ Firestore │ 127.0.0.1:8080 │ http://localhost:4000/firestore │
└────────────────┴────────────────┴─────────────────────────────────┘
Emulator Hub running at localhost:4400
Other reserved ports: 4500
Firestore and Auth emulators are on 127.0.0.1 because setting it to the default "localhost" caused it to fail.
index.js
const functions = require("firebase-functions");
const admin = require("firebase-admin");
admin.initializeApp();
exports.newDoc = functions.firestore
.document("/{collection}/{docID}")
.onCreate((snapshot, context) => {
console.log(snapshot.data());
});
What I've tried
When any new records are added, even if the Admin SDK has added them, the documents are not read.
I've reset all security rules as they restricted read/write access.
I've tried the production environment instead of the emulator. I didn't expect this to work as the functions aren't deployed

Answer 1

It turns out, this is actually the correct setup for the JavaScript cloud function emulator. There was a problem in my environment where a restart was required.
For those having the same issue, I would try the same types of troubleshooting:
Try making the path use all wildcards to see if the path is the problem
To make sure it's not a problem with your current environment.