How to import test data into Firebase Firestore emulator from production for easy testing?

One way to persist your data is by exporting to directory on exit and on start import the same directory

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

You can manually export from Production and then import into the Firestore emulator.

Start by doing an export of your production data to a file. In the example, I export just the "users" collection within an onRequest function so I can kick-off by calling the URL. Note, this this function will not handle subcollections.

exports.exportFirestore = functions.https.onRequest(async (req, res) => { const fs = require("fs"); const collection = "users"; const fileName = "fs-export.json"; const exportedData = {}; exportedData[collection] = {}; await admin .firestore() .collection(collection) .get() .then((snapshot) => { return snapshot.forEach((doc) => { exportedData[collection][doc.id] = doc.data(); }); }) .catch(console.error); fs.writeFile(fileName, JSON.stringify(exportedData), (err) => { if (err) { console.log(err); } else { console.log("Firestore Export Complete."); res.send("Firestore Export Complete."); } }); }); 

Next, import the file into the local Firestore emulator. Very important: be sure to have the Firestore emulator running otherwise you'll be importing your data back to prod. Be sure to check that Firestore is running by checking the web UI: http://localhost:4000. Start the emulator with: firebase emulators:start

exports.importFirestore = functions.https.onRequest(async (req, res) => { const fs = require("fs"); let collection; const fileName = "fs-export.json"; const exportedData = {}; exportedData[collection] = {}; fs.readFile(fileName, "utf8", async (err, data) => { if (err) { return console.log(err); } const arr = JSON.parse(data); const batch = admin.firestore().batch(); for (let i in arr) { collection = i; for (let doc in arr[i]) { if (arr[i].hasOwnProperty(doc)) { const ref = admin.firestore().collection(collection).doc(doc); batch.set(ref, arr[i][doc]); } else { console.log("Missing:", JSON.stringify(doc, null, 2)); } } } await batch .commit() .then(() => { return console.log("Import to Firestore Complete"); }) .catch(console.error); return res.send("Import to Firestore Complete"); }); }); 

You can do this using gcloud (Google Cloud's CLI). It does take several commands:

First, create a firestore export of your Firestore staging (Using production database for local development could be potentially dangerous) database (Make sure this bucket exists first!):

gcloud firestore export gs://{BUCKET}/{DIRECTORY} 

Then, download the data from this bucket:

gsutil -m cp -r gs://{BUCKET}/{DIRECTORY} ./{LOCAL_DIRECTORY_NAME} 

Finally, run the emulators with this command:

firebase emulators:start --import ./{LOCAL_DIRECTORY_NAME} 

This should give you a local copy of your staging database to work on.

My answer is heavily inspired by @Geoffrey Bourne's answer, but I had to modify some stuff and figure out more details to get it working.

First, I upload the exportFirestore to Cloud Functions (production). When I run it through this URL https://us-central1-<project-id>.cloudfunctions.net/exportFirestore, I get a file DOWNLOADED, as Cloud Functions are read-only

The below code is for one collection named fl_content, I'll consider expanding it to multiple collections

export const exportFirestore = functions.https.onRequest(async (req, res) => { const collection = "fl_content"; const exportedData: any = {}; exportedData[collection] = {}; await admin .firestore() .collection(collection) .get() .then((snapshot) => snapshot.forEach((doc) => exportedData[collection][doc.id] = doc.data())) .catch(console.error); const data = JSON.stringify(exportedData); res.setHeader('Content-disposition', 'attachment; filename=fire-export.json'); res.setHeader('Content-type', 'application/json'); res.write(data, function () { res.end(); }); }) 

Once you have the file fire-export.json downloaded, put it inside the functions folder. Then open the URL for the import function (locally) http://localhost:5001/<project-id>/us-central1/importFirestore. Make sure the collection variable is the same in the export and import.

export const importFirestore = functions.https.onRequest(async (req, res) => { const fs = require("fs"); const collection = "fl_content"; const fileName = "fire-export.json"; const exportedData: any = {}; exportedData[collection] = {}; fs.readFile(fileName, "utf8", async (err: any, data: any) => { if (err) { res.send(err); functions.logger.error(err) return; } const arr = JSON.parse(data); const batch = admin.firestore().batch(); for (const i in arr) { for (const doc in arr[i]) { if (arr[i].hasOwnProperty(doc)) { const ref = admin.firestore().collection(collection).doc(doc); batch.set(ref, arr[i][doc]); } else { functions.logger.error("Missing:", JSON.stringify(doc, null, 2)); } } } await batch .commit() .then(() => console.log("Import to Firestore Complete")) .catch(console.error); res.send("Import to Firestore Complete"); }); });