Export and snapshots

An export is a folder of your data in the official emulator’s format. Use one to make a seed, to keep a snapshot of data you work on, or to take your data to the official emulator and back. Firenook exports Firestore, Auth and Storage.

Export while the emulators run

emulators:export asks the running suite to write its data to a folder:

$ npx firenook emulators:export ./exports/before-migration
Found running emulator hub for project demo-shop at http://127.0.0.1:4400; exporting firestore, auth, storage to ~/demo-shop/exports/before-migration
Export complete: ~/demo-shop/exports/before-migration

It needs a running suite, as the official command does. With the emulators stopped, it says so:

Firenook: Did not find a running emulator hub for project demo-shop (tried http://127.0.0.1:4400): ECONNREFUSED. Start it with firenook emulators:start.

The command finds the suite by its project id, through the same hub file the official CLI uses. When two suites run with one project id, such as two Git worktrees, it reaches the one started from the folder you run it in. Elsewhere it asks for --hub-port; see troubleshooting.

Option	What it does
--only firestore,auth,storage	Exports only the services you name
--force	Writes into a folder that holds other files
--json	Prints the result as one JSON line
-P, --project ID	The project, when you are not in its folder
--hub-port PORT	The suite whose hub listens on this port, and no other

The destination may not be the project folder, the current folder or a parent of either. A folder that holds files but no firebase-export-metadata.json needs --force:

Firenook: ~/demo-shop/notempty is not empty and holds no firebase-export-metadata.json; re-run with --force to overwrite its contents

A folder that already holds an export is written over without --force.

Export at the stop

--export-on-exit writes an export when you stop Firenook:

npx firenook emulators:start --import ./data --export-on-exit ./data

Without a folder, it writes back into the --import folder, as in the official CLI, so --import ./data --export-on-exit keeps ./data up to date. Without --import, name the folder:

Firenook: --export-on-exit requires --import or an explicit destination

The stop takes as long as the export, and the terminal says where it went:

     19:47:00    ✓ stopped          90 ms  exported to snapshot

Snapshots of kept data

Data kept with --keep-data is a working store, not an export. To take a copy you can load anywhere, use any of these while the emulators run:

• Press e in the terminal. The snapshot goes to .firenook/exports/<date>-<time>:

       19:46:58    ✓ exported         25 ms  .firenook/exports/2026-10-22-194658

• Run npx firenook emulators:export ./snapshots/today from another terminal.

• In the console, the Overview’s Data card downloads a snapshot as a zip of an export, or saves it to a folder on your machine.

To write a snapshot at every stop, add --export-on-exit with a folder:

npx firenook emulators:start --keep-data --export-on-exit ./snapshot

With a seed, the folder must be another one: Firenook refuses to export into the seed it keeps data from (seeds and imports).

To go back to a snapshot later, import it into a new state folder:

npx firenook emulators:start --import ./snapshot --state-dir ./.firenook/from-snapshot --resume-state

Move data to the official emulator and back

Firenook reads and writes the official export format. A Firenook export of 2,105 documents, one user and one file loaded in the official emulator (firebase-tools 13.4.0), and that emulator’s export loaded back into Firenook with the same counts.

1. With Firenook running, export: npx firenook emulators:export ./export. Or stop it with --export-on-exit ./export set.

2. Stop Firenook with q or Ctrl-C, and wait for it to exit.

3. Start the official emulator on the export:

   firebase emulators:start --import ./export --export-on-exit ./export

4. To come back, stop the official emulator, then start Firenook on its export: npx firenook emulators:start --import ./export --keep-data.

Never run both at once on the same ports, and never point the official emulator at Firenook’s .firenook/ folder: each needs its own working data.

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