I needed to send push notifications to a mobile app from my elixir server. I wanted to use Firebase Cloud Messaging’s “topics” so I didn’t have to keep track of every individiual device’s token, which requires using the newer FCM HTTP v1 API. All the other libraries I found on hex (like Pigeon) used the deprecated Legacy HTTP protocol. Versions of this code have been in production since April 2019.
From the README:
FirebaseCloudMessagingHttpV1Api
Send Firebase Cloud Messaging Push Notifications via the FCM HTTP v1 API.
Use goth to acquire authentication tokens.
Example
{:ok, %Goth.Token{token: token}} =
Goth.Token.for_scope("https://www.googleapis.com/auth/firebase.messaging")
%Google.Firebase.FCM.V1.Message{
notification: %Google.Firebase.FCM.V1.Notification{
title: "notification title",
body: "notification body"
},
android: %Google.Firebase.FCM.V1.AndroidConfig{
priority: "HIGH",
ttl: "86400s",
notification: %Google.Firebase.FCM.V1.AndroidNotification{
channel_id: "my-android-channel"
}
},
topic: "my-topic"
}
|> Google.Firebase.FCM.V1.Message.send("projects/my-firebase-project", token)