Firebase Subcollections

[RSelwa]

It would be cool to work with firebase subcollection to write and update data 😍

[maxnowack]

I'm not that familiar with firebase. What exactly are you trying to do with it and how would it be used with SignalDB?

[RSelwa]

We're working with firebase and we're trying to implement an ORM, but firebase works with sub-collection concepts. For exemple, our users have a sub coll of their preferences so basically the request should be something like '/users/id_user/preferences/id_of_preferences'. But in signalDb (as far as I know) you need to declare the collection path at initialization with the createFirebasePersistenceAdapter. But here we need to know the userId first to declare the good path.
Currently, we'me made a little trick: we declared some collections knowed as sub-coll and if this is the case, we pass a ref in the object (wich gonna be /user/<XYZ>/preferences/) and we overide the collection path declared before with it.

Let me know what do you think about it 🤗

[maxnowack]

I've updated the examples last week to use the new SyncManager (see https://github.com/maxnowack/signaldb/blob/main/examples/firebase/src/system/syncManager.ts).
Please also take a look at the implementation documentation. There is an example how to specify an api path when using a REST API. For your use case it could be used similar

[RSelwa]

Yes, it work perfectly fine for collections, but for sub-collections, it's not possible without doing tricks. For Firestore, it's not like an REST API.
It's collection name, with sub-collection, we can't declare it in the sync manager. Here's an example:

registerRemoteChange({ name }, onChange) {
   onSnapshot(collection(db, name), () => {
     void onChange()
   })

   return Promise.resolve()
 },

We don't know the id of the document wich our sub-collection is from

[Cmacu]

You can pass extra parameters to syncManager.addCollection and you should receive them in the first argument of registerRemoteChange. See here: Adding collections