如何将非持久值发送到 Cloud Firestore？

Question

I want to send some value for a field to Cloud Firestore , but I dont want to be persist(saved) in Cloud Firestore .

Code:

const message = {
  persistentData: {
     id: 'dSXYdieiwoDUEUWOssd',
     text: 'Hi dear how are you',
     date: new Date();
  },

  nonPersistentData: {
    securityCode: 393929949
  }
};

db.collection('messages').doc(message.persistentData.id).set(message).catch(e => {});

In above code I want to persit (save) persistentData , but I dont want to save nonPersistentData online nor offline , because I only need them to check real data in Firestore rule . So I dont want they should be accessible in cache(offline) or server(online) ...

Answer 1

This is simply not possible with firestore. There is a similar question here . You need to separate the data into public (persistent) and private data (non-persistent). One possible solution will be-

1. From the client, push the private data which contains the securityCode to a new collection called securityCodes and store the id of the new entry. Because you don't want this info to be available to anyone, you can add a security rule

match /securityCodes/{securityCode} {
  // No one can read the value from this collection, but only create
  allow create: true;
}

2. In your public data, add the id of the previously added document

data = {
  id: 'dSXYdieiwoDUEUWOssd',
  text: 'Hi dear how are you',
  date: new Date(),
  securityId: <id of the secretCode entry>
}

3. In your security rules, get the secret code using the securityId you are sending with the public data. Example-

match /collectionId/documentId {
  allow create: if get(/secretCodes/$(request.resource.data.secretId)) == 'someknowncode'
}