Google FCM
Google Firebase Cloud Messaging (FCM) is a cross-platform messaging solution that lets you reliably deliver messages at no cost.
Using FCM, you can notify a client app that new email or other data is available to sync. You can send notification messages to drive user re-engagement and retention. For use cases such as instant messaging, a message can transfer a payload of up to 4KB to a client app.
The Alpakka Google Firebase Cloud Messaging connector provides a way to send notifications with Firebase Cloud Messaging.
Project Info: Alpakka Google Firebase Cloud Messaging (FCM) | |
---|---|
Artifact | com.lightbend.akka
akka-stream-alpakka-google-fcm
1.1.2
|
JDK versions | OpenJDK 8 |
Scala versions | 2.12.7, 2.11.12 |
JPMS module name | akka.stream.alpakka.google.firebase.fcm |
License | |
Readiness level |
Since 0.18, 2018-03-28
|
Home page | https://doc.akka.io/docs/alpakka/current |
API documentation | |
Forums | |
Release notes | In the documentation |
Issues | Github issues |
Sources | https://github.com/akka/alpakka |
Artifacts
- sbt
libraryDependencies += "com.lightbend.akka" %% "akka-stream-alpakka-google-fcm" % "1.1.2"
- Maven
<dependency> <groupId>com.lightbend.akka</groupId> <artifactId>akka-stream-alpakka-google-fcm_2.12</artifactId> <version>1.1.2</version> </dependency>
- Gradle
dependencies { compile group: 'com.lightbend.akka', name: 'akka-stream-alpakka-google-fcm_2.12', version: '1.1.2' }
The table below shows direct dependencies of this module and the second tab shows all libraries it depends on transitively.
- Direct dependencies
Organization Artifact Version License com.pauldijou jwt-core_2.12 2.1.0 Apache-2.0 com.typesafe.akka akka-http-spray-json_2.12 10.1.10 Apache-2.0 com.typesafe.akka akka-http_2.12 10.1.10 Apache-2.0 com.typesafe.akka akka-stream_2.12 2.5.23 Apache License, Version 2.0 org.scala-lang scala-library 2.12.7 BSD 3-Clause - Dependency tree
com.pauldijou jwt-core_2.12 2.1.0 Apache-2.0 org.bouncycastle bcpkix-jdk15on 1.60 Bouncy Castle Licence org.bouncycastle bcprov-jdk15on 1.60 Bouncy Castle Licence org.scala-lang scala-library 2.12.7 BSD 3-Clause com.typesafe.akka akka-http-spray-json_2.12 10.1.10 Apache-2.0 com.typesafe.akka akka-http_2.12 10.1.10 Apache-2.0 com.typesafe.akka akka-http-core_2.12 10.1.10 Apache-2.0 com.typesafe.akka akka-parsing_2.12 10.1.10 Apache-2.0 org.scala-lang scala-library 2.12.7 BSD 3-Clause org.scala-lang scala-library 2.12.7 BSD 3-Clause org.scala-lang scala-library 2.12.7 BSD 3-Clause io.spray spray-json_2.12 1.3.5 Apache 2 org.scala-lang scala-library 2.12.7 BSD 3-Clause org.scala-lang scala-library 2.12.7 BSD 3-Clause com.typesafe.akka akka-http_2.12 10.1.10 Apache-2.0 com.typesafe.akka akka-http-core_2.12 10.1.10 Apache-2.0 com.typesafe.akka akka-parsing_2.12 10.1.10 Apache-2.0 org.scala-lang scala-library 2.12.7 BSD 3-Clause org.scala-lang scala-library 2.12.7 BSD 3-Clause org.scala-lang scala-library 2.12.7 BSD 3-Clause com.typesafe.akka akka-stream_2.12 2.5.23 Apache License, Version 2.0 com.typesafe.akka akka-actor_2.12 2.5.23 Apache License, Version 2.0 com.typesafe config 1.3.3 Apache License, Version 2.0 org.scala-lang.modules scala-java8-compat_2.12 0.8.0 BSD 3-clause org.scala-lang scala-library 2.12.7 BSD 3-Clause org.scala-lang scala-library 2.12.7 BSD 3-Clause com.typesafe.akka akka-protobuf_2.12 2.5.23 Apache License, Version 2.0 org.scala-lang scala-library 2.12.7 BSD 3-Clause com.typesafe ssl-config-core_2.12 0.3.7 Apache-2.0 com.typesafe config 1.3.3 Apache License, Version 2.0 org.scala-lang.modules scala-parser-combinators_2.12 1.1.1 BSD 3-clause org.scala-lang scala-library 2.12.7 BSD 3-Clause org.scala-lang scala-library 2.12.7 BSD 3-Clause org.reactivestreams reactive-streams 1.0.2 CC0 org.scala-lang scala-library 2.12.7 BSD 3-Clause org.scala-lang scala-library 2.12.7 BSD 3-Clause
Settings
Prepare your credentials for access to FCM.
- Scala
-
val privateKey = """-----BEGIN RSA PRIVATE KEY----- |MIIBOgIBAAJBAJHPYfmEpShPxAGP12oyPg0CiL1zmd2V84K5dgzhR9TFpkAp2kl2 |9BTc8jbAY0dQW4Zux+hyKxd6uANBKHOWacUCAwEAAQJAQVyXbMS7TGDFWnXieKZh |Dm/uYA6sEJqheB4u/wMVshjcQdHbi6Rr0kv7dCLbJz2v9bVmFu5i8aFnJy1MJOpA |2QIhAPyEAaVfDqJGjVfryZDCaxrsREmdKDlmIppFy78/d8DHAiEAk9JyTHcapckD |uSyaE6EaqKKfyRwSfUGO1VJXmPjPDRMCIF9N900SDnTiye/4FxBiwIfdynw6K3dW |fBLb6uVYr/r7AiBUu/p26IMm6y4uNGnxvJSqe+X6AxR6Jl043OWHs4AEbwIhANuz |Ay3MKOeoVbx0L+ruVRY5fkW+oLHbMGtQ9dZq7Dp9 |-----END RSA PRIVATE KEY-----""".stripMargin val clientEmail = "[email protected]" val projectId = "test-XXXXX" val fcmConfig = FcmSettings(clientEmail, privateKey, projectId)
- Java
-
String privateKey = "-----BEGIN RSA PRIVATE KEY-----\n" + "MIIBOgIBAAJBAJHPYfmEpShPxAGP12oyPg0CiL1zmd2V84K5dgzhR9TFpkAp2kl2\n" + "9BTc8jbAY0dQW4Zux+hyKxd6uANBKHOWacUCAwEAAQJAQVyXbMS7TGDFWnXieKZh\n" + "Dm/uYA6sEJqheB4u/wMVshjcQdHbi6Rr0kv7dCLbJz2v9bVmFu5i8aFnJy1MJOpA\n" + "2QIhAPyEAaVfDqJGjVfryZDCaxrsREmdKDlmIppFy78/d8DHAiEAk9JyTHcapckD\n" + "uSyaE6EaqKKfyRwSfUGO1VJXmPjPDRMCIF9N900SDnTiye/4FxBiwIfdynw6K3dW\n" + "fBLb6uVYr/r7AiBUu/p26IMm6y4uNGnxvJSqe+X6AxR6Jl043OWHs4AEbwIhANuz\n" + "Ay3MKOeoVbx0L+ruVRY5fkW+oLHbMGtQ9dZq7Dp9\n" + "-----END RSA PRIVATE KEY-----"; String clientEmail = "[email protected]"; String projectId = "test-XXXXX"; FcmSettings fcmConfig = FcmSettings.create(clientEmail, privateKey, projectId);
The last two parameters in the above example are the predefined values. You can send test notifications (so called validate only). And you can set the number of maximum concurrent connections. There is a limitation in the docs; from one IP you can have maximum 1k pending connections, and you may need to configure akka.http.host-connection-pool.max-open-requests
in your application.conf.
Sending notifications
To send a notification message create your notification object, and send it!
- Scala
-
import akka.stream.alpakka.google.firebase.fcm.FcmNotificationModels._ import akka.stream.alpakka.google.firebase.fcm.scaladsl.GoogleFcm import akka.stream.alpakka.google.firebase.fcm._ val result1: Future[immutable.Seq[FcmResponse]] = Source .single(notification) .via(GoogleFcm.send(fcmConfig)) .map { case res @ FcmSuccessResponse(name) => println(s"Successful $name") res case res @ FcmErrorResponse(errorMessage) => println(s"Send error $errorMessage") res } .runWith(Sink.seq)
- Java
-
import akka.stream.alpakka.google.firebase.fcm.*; import akka.stream.alpakka.google.firebase.fcm.javadsl.GoogleFcm; CompletionStage<List<FcmResponse>> result1 = Source.single(notification) .via(GoogleFcm.send(fcmConfig)) .map( res -> { if (res.isSuccess()) { FcmSuccessResponse response = (FcmSuccessResponse) res; System.out.println("Successful " + response.getName()); } else { FcmErrorResponse response = (FcmErrorResponse) res; System.out.println("Send error " + response.getRawError()); } return res; }) .runWith(Sink.seq(), materializer);
With this type of send you can get responses from the server. These responses can be `FcmSuccessResponse`
or `FcmErrorResponse`
. You can choose what you want to do with this information, but keep in mind if you try to resend the failed messages you will need to use exponential backoff! (see Akka docs RestartFlow.onFailuresWithBackoff
)
If you don’t care if the notification was sent successfully, you may use fireAndForget
.
- Scala
-
import akka.stream.alpakka.google.firebase.fcm.FcmNotificationModels._ import akka.stream.alpakka.google.firebase.fcm.scaladsl.GoogleFcm import akka.stream.alpakka.google.firebase.fcm._ val notification = FcmNotification("Test", "This is a test notification!", Token("token")) Source .single(notification) .runWith(GoogleFcm.fireAndForget(fcmConfig))
- Java
-
import akka.stream.alpakka.google.firebase.fcm.*; import akka.stream.alpakka.google.firebase.fcm.javadsl.GoogleFcm; FcmNotification notification = FcmNotification.basic( "Test", "This is a test notification!", new FcmNotificationModels.Token("token")); Source.single(notification).runWith(GoogleFcm.fireAndForget(fcmConfig), materializer);
With fire and forget you will just send messages and ignore all the errors.
To help the integration and error handling or logging, there is a variation of the flow where you can send data beside your notification.
- Scala
-
import akka.stream.alpakka.google.firebase.fcm.FcmNotificationModels._ import akka.stream.alpakka.google.firebase.fcm.scaladsl.GoogleFcm import akka.stream.alpakka.google.firebase.fcm._ val result2: Future[immutable.Seq[(FcmResponse, String)]] = Source .single((notification, "superData")) .via(GoogleFcm.sendWithPassThrough(fcmConfig)) .runWith(Sink.seq)
- Java
-
import akka.stream.alpakka.google.firebase.fcm.*; import akka.stream.alpakka.google.firebase.fcm.javadsl.GoogleFcm; CompletionStage<List<Pair<FcmResponse, String>>> result2 = Source.single(Pair.create(notification, "superData")) .via(GoogleFcm.sendWithPassThrough(fcmConfig)) .runWith(Sink.seq(), materializer);
Here I send a simple string, but you could use any type.
Scala only
You can build any notification described in the original documentation. It can be done by hand, or using some builder method. If you build your notification from scratch with options (and not with the provided builders), worth to check isSendable before sending.
- Scala
-
val buildedNotification = FcmNotification.empty .withTarget(Topic("testers")) .withBasicNotification("title", "body") //.withAndroidConfig(AndroidConfig(...)) //.withApnsConfig(ApnsConfig(...)) .withWebPushConfig( WebPushConfig( headers = Map.empty, data = Map.empty, WebPushNotification("web-title", "web-body", "http://example.com/icon.png") ) ) val sendable = buildedNotification.isSendable
There is a condition builder too.
- Scala
-
import akka.stream.alpakka.google.firebase.fcm.FcmNotificationModels.Condition.{Topic => CTopic} val condition = Condition(CTopic("TopicA") && (CTopic("TopicB") || (CTopic("TopicC") && !CTopic("TopicD")))) val conditioneddNotification = FcmNotification("Test", "This is a test notification!", condition)