Communicating with logged on users after trigger fires

MongoDB Atlas App Services & Realm Atlas Triggers & Functions
1

Taking a multi-user scrabble game as an example - 5 players in game - current player makes move which is sent to realm function - trigger fires on update to game table with new letter - game table contains player info for that game (disconnect at the moment between player info and info needed to communicate/push to that user) - is it possible to use realm features to send new letter back to all players of that game? looking at sync functionality but not sure it is relevant to situation above?

edit: just found “built-in services: push notification” … is this a good avenue to explore? Except users could be on desktop also.

2

Hi @Mic_Cross,
The Realm sync which is in beta might be an option.

However, I would explore using a collection.watch method from the relevant sdk of your choice.

Example see the react sdk:
https://docs.mongodb.com/realm-sdks/js/10.0.0-beta.9/Realm.RemoteMongoDBCollection.html

This is based in MongoDB change streams which listen to configure data changes and allow you to trigger an application logic on every relevant change.

Thanks,
Pavel

3

I am using WebSDK with GraphQL, ApolloClient etc - just found this in readme for RealmWeb: “the Realm Web project will not include a Realm Sync client in any foreseeable future.” " A limited selection of services are implemented at the moment:

  • Remote MongoDB (watching a collection is not yet implemented)." Explains why ‘const app = new RealmWeb.App({ id: REALM_APP_ID });’ creates an app object with no .objects, no watch etc.
4

We’re currently working on bringing MongoDB watch support to Realm Web (and it is already available in the legacy Stitch SDK for browsers).

A Realm Sync client in the Realm Web SDK is a different story (and technically a very different thing), as that won’t be available in any foreseeable future.

5

went back to mongodb stitch tutorial and have “add collection-level watch” working.

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