How do import data from cloud firestore to the local emulator?

问题

I want to be able to run cloud functions locally and debug against a copy from the production data. Is there a way to copy the data that is online to the local firestore emulator?

回答1:

You can use the firestore-backup-restore to export and import your production data as JSON files.

I wrote a quick hack to allow for importing these JSON in the Firebase Simulator Firestore instance.

I proposed a pull request and made this npm module in the meantime.

You can use it this way:

const firestoreService = require('@crapougnax/firestore-export-import')
const path = require('path')

// list of JSON files generated with the export service
// Must be in the same folder as this script
const collections = ['languages', 'roles']

// Start your firestore emulator for (at least) firestore
// firebase emulators:start --only firestore

// Initiate Firebase Test App
const db = firestoreService.initializeTestApp('test', {
   uid: 'john',
   email: 'john@doe.com',
})

// Start importing your data
let promises = []
try {
   collections.map(collection =>
      promises.push(
         firestoreService.fixtures(
            path.resolve(__dirname, `./${collection}.json`),
            [],
            [],
            db,
         ),
      ),
   )
   Promise.all(promises).then(process.exit)
} catch (err) {
   console.error(err)
}

Obviously, since this data won't persist in the emulator, you'll typically inject them in the before() function of your test suite or even before every test.

Hope this helps.

回答2:

There is no built-in way to copy data from a cloud project to the local emulator. Since the emulator doesn't persist any data, you will have to re-generate the initial data set on every run.

来源：https://stackoverflow.com/questions/57838764/how-do-import-data-from-cloud-firestore-to-the-local-emulator