firebase-tools: Firestore data in emulator not showing up in emulator UI

@charles-allen you’ve got it exactly right. A fake project ID will allow database writes but not much else. If you want to start the Emulator Suite with a fake project ID just do this:

firebase --project="foobar123" emulators:start

Found the answer – when calling admin.initializeApp() you need to set the correct projectId, then the data will show up.

@charles-allen you’ve got it exactly right. A fake project ID will allow database writes but not much else. If you want to start the Emulator Suite with a fake project ID just do this:

firebase --project="foobar123" emulators:start

Thanks! That was the missing piece of the puzzle.

Can I suggest (or even PR) to add the above to the docs here (where it mentions setting the fake project ID; since the snipper only shows the Admin SDK side, which doesn’t fully work without the above).

I actually Googled quickly, and I can’t find any reference to --project in the docs at all (only on other sites).

To add to this, I got the same issue when creating different project environments via firebase use [your environment name]. The local emulator was working, just not showing any data. Once I switched my config settings to the correct environment, all was well and data started showing up in the emulator.

@samtstern - In my case, I’m pretty sure that this error is the result of attempting to use a fake id (intentionally or accidentally). When I initialize with the same id as firebase use, everything works; when using a fake ID:

• ✓ Read/write works
• ✘ No data in Emulator UI
• ✘ No CF trigger console.log in shell (I didn’t verify if they fire)
• ✘ Cannot auth from client SDK

Based on the docs and your comments, I’m not convinced it’s even possible.

From the docs you quoted:

Note that you do not need to use your real Firebase project ID

However, over here you said:

@cbdeveloper yes that’s correct, the emulator suite emulates the currently active project as determined by firebase-tools. That’s the project which will be shown in the Emulator UI and that’s also the project which will be used when configuring Cloud Functions triggers locally.

To my knowledge, the current project is set using firebase use; when I attempt this with a fake id, I get this error:

firebase use <FAKE_ID>
Error: Invalid project selection, please verify project <FAKE_ID> exists and you have access.

So how is it possible to set a fake id for firebase-tools, and thus for the emulator?

My script does set the projectId, and I still have this issue. I am running firebase 8.16.2.

My scripts are reading from and writing to the emulator fine, but if I go into the Emulator UI, there is no data shown. I can only view the collections, documents, subcollections, etc. if I manually create the top-level collection and documents. If I use the Cloud Firestore without the emulator, the same scripts work fine and I can view all the data in the UI without any manual intervention. Please advise.

@samtstern Well that is absolutely delightful for a person who knows where to find it. Google documentation together with Microsoft has always been a wall-of-text mess.

Found the answer – when calling admin.initializeApp() you need to set the correct projectId, then the data will show up.

Embarrassing that this isn’t in the documentation more clearly.

I am using docker and have never gotten data to load, even with admin.initilizeApp using credentials for my existing project, firebase use my-project etc. (also doesn’t work without docker and just using firebase --project project-id emulators:start, no data in ui)

how was this issue solved? I am still facing it

I had the same problem, using python library, and what worked for me was instantiating the firestore client with db = firestore.client() not db = firestore.Client() (Client capitalized). With instance and executing db.project returns different responses:

• with client => <my_project_id>
• with Client => google-cloud-firestore-emulator

@basickarl calling something embarrassing isn’t very constructive, also this IS in the documentation:

Link: https://firebase.google.com/docs/emulator-suite/connect_firestore#admin_sdks

Screenshot:

Adding my findings here. I was basically at the same place as this comment https://github.com/firebase/firebase-tools/issues/2365#issuecomment-749396838 and had resigned to use a real project id when running the emulator so that the active project in the CLI (firebase use) would match admin.initializeApp({ projectId: xx }) and firebase --project project-id emulators:start.

However, as stated in the Emulator docs:

For any products you are not emulating, your apps and code will interact with the live resource (database instance, storage bucket, function, etc.).

This felt really bad tbh, a loaded gun waiting to go off when someone thinks they’re working against an emulator and does a mistake that mutates real data.

However what the docs also says is interesting:

Demo: A demo Firebase project has no real Firebase configuration and no live resources. These projects are usually accessed via codelabs or other tutorials.

When working with demo Firebase projects, your apps and code interact with emulators only. If your app attempts to interact with a resource for which an emulator isn’t running, that code will fail.

Project IDs for demo projects have the demo- prefix.

This was news to me. Turns out if you use the demo- prefix in your non-existing, fake project id, it won’t matter whatever is active in the CLI (firebase use).

The final state that got everything working for me:

• Start emulators: npx firebase --project=demo-eaardal-emulator emulators:start"
• The command running the script using firestore (npm run generate:local):

"generate:local": "env-cmd --file=.env.local ts-node ./src/generate.ts",

.env.local:

FIRESTORE_EMULATOR_HOST=localhost:8080
PROJECT_ID=demo-eaardal-emulator
NODE_ENV=development

• In code (generate.ts, writing data to Firestore), using the JavaScript firebase-admin SDK:

import { initializeApp } from "firebase-admin/app";
const app = initializeApp({ projectId: process.env.PROJECT_ID });
// emulator is enabled by setting FIRESTORE_EMULATOR_HOST when using firebase-admin, other SDKs might set it up differently

Data is showing in the Firestore Emulator UI both when using --export-on-exit ./localdata --import ./localdata and not.

Just to verify, I have a real test project set as my active CLI project (firebase use {real test project}) and can verify that if I try to use a non-emulated service that exists and is active in the real test project, it will simply fail and not fall back on using the real project.

Hope this helps!