Messaging

Overview

FCM and tokens

Fireship uses FCM to send messages to devices.

The tokens are saved under /user-fcm-tokens/<token> { uid: [user uid], platform: [android or ios]}. So, if you want to get the tokens of a user, you must get the tokens by searching the uid.

Sending messages to user

One user may use multiple devices and one device may have multiple tokens. So, if the app sends a message to A, the app must query to get the tokens of A in /user-fcm-tokens

The code below shows how send a message to multiple users.

final List<String> uids = some.users;

//sending notification to the list of uids
await MessagingService.instance.sendTo(
  uids: uids,
  title: '... message title ...',
  body: '... message body ...',
  image: url,
);

To use this method, The firebase cloud function named sendPushNotifications in firebase/functions/src/messaging/functions.ts must be installed. See installation on how to install firebsae functions.

Sending messages for forum category subscription and chat room subscription

There are firebase cloud functions that work with fireship for sending messages to subscribers on forum categories and chat rooms.

You will need to install sendMessagesToCategorySubscribers and sendMessagesToChatRoomSubscribers in firebase/functions/src/messaging/functions.ts to make it work.

The source code is under firebase/functions and the test code is under firebase/functions/tests.

Unit testing

See firebase/functions/tests folder for unit testing on push notification. To run the unit test code, you need to set the environment variable - GOOGLE_APPLICATION_CREDENTIAILS