Droid what is data push

Whenever you want to send values only to particular platforms, don't use common fields; use platform-specific fields. For example, to send a notification only to Apple platforms and web but not to Android, you must use two separate sets of fields, one for Apple and one for web. When you are sending messages with specific delivery options , use platform-specific fields to set them. You can specify different values per platform if you want. However, even when you want to set essentially the same value across platforms, you must use platform-specific fields.

This is because each platform may interpret the value slightly differently—for example, time-to-live is set on Android as an expiration time in seconds, while on Apple it is set as an expiration date. The following v1 send request sends a common notification title and content to all platforms, but also sends some platform-specific overrides. Specifically, the request:. See the HTTP v1 reference documentation for complete detail on the keys available in platform-specific blocks in the message body.

For more information about building send requests that contain the message body, see Build Send Requests. FCM provides a specific set of delivery options for messages sent to Android devices, and allows for similar options on Apple platforms and web. For details, see descriptions in this section and related reference documentation. Non-collapsible and collapsible messages. A non-collapsible message denotes that each individual message is delivered to the device.

A non-collapsible message delivers some useful content, as opposed to a collapsible message like a content-free "ping" to the mobile app to contact the server to fetch data. Some typical use cases of non-collapsible messages are chat messages or critical messages. For example, in an IM app, you would want to deliver every message, because every message has different content.

For Android there is a limit of messages that can be stored without collapsing. If the limit is reached, all stored messages are discarded. When the device is back online, it receives a special message indicating that the limit was reached. The app can then handle the situation properly, typically by requesting a full sync from the app server.

A collapsible message is a message that may be replaced by a new message if it has yet to be delivered to the device. A common use cases of collapsible messages are messages used to tell a mobile app to sync data from the server. An example would be a sports app that updates users with the latest score. Only the most recent message is relevant. By default, the collapse key is the app package name registered in the Firebase console. The FCM server can simultaneously store four different collapsible messages per device, each with a different collapse key.

If you exceed this number, FCM only keeps four collapse keys, with no guarantees about which ones are kept. Collapsible messages are a better choice from a performance standpoint, provided your app doesn't need to use non-collapsible messages. However, if you use collapsible messages, remember that FCM only allows a maximum of four different collapse keys to be used by FCM per registration token at any given time.

You must not exceed this number, or it could cause unpredictable consequences. Use scenario How to send Non-collapsible Every message is important to the client app and needs to be delivered. Except for notification messages, all messages are non-collapsible by default.

Collapsible When there is a newer message that renders an older, related message irrelevant to the client app, FCM replaces the older message. For example: messages used to initiate a data sync from the server, or outdated notification messages. Setting the priority of a message. You have two options for assigning delivery priority to downstream messages on Android: normal and high priority.

Delivery of normal and high priority messages works like this:. Normal priority. This is the default priority for data messages. Normal priority messages are delivered immediately when the app is in the foreground. When the device is in Doze, delivery may be delayed to conserve battery. For less time-sensitive messages, such as notifications of new email, keeping your UI in sync, or syncing app data in the background, choose normal delivery priority.

When receiving a normal priority message on Android that requests a background data sync for your app, you can schedule a task with WorkManager to handle it when the network is available.

High priority. FCM attempts to deliver high priority messages immediately, allowing the FCM service to wake a sleeping device when necessary and to run some limited processing including very limited network access. High priority messages generally should result in user interaction with your app or its notifications. If FCM detects a pattern in which they don't, your messages may be de-prioritized.

Android P introduced app standby buckets which limit the number of FCM high priority messages you can send to your app that don't result in the user using your app or viewing a notification. If, in response to a high priority message, a notification is displayed in a way that is visible to the user, then your app standby bucket quota will not be consumed by that message.

Because a small portion of the Android mobile population are on high latency networks, avoid opening a connection to your servers before displaying a notification. Calling back to the server before the end of the allowed processing time may be risky for users on high latency networks. Instead, include the notification content in the FCM message and display it immediately.

If you need to sync for additional in-app content on Android, you can schedule a task with WorkManager to handle that in the background. Here is an example of a normal priority message sent via the FCM HTTP v1 protocol to notify a magazine subscriber that new content is available to download:. Setting the lifespan of a message. FCM usually delivers messages immediately after they are sent. However, this might not always be possible. For example, if the platform is Android, the device could be turned off, offline, or otherwise unavailable.

Or FCM might intentionally delay messages to prevent an app from consuming excessive resources and negatively affecting battery life. What the app obtains actually is the value of msgId of the notification message through getMessageId from the data obtained by onMessageReceived. Obtaining Data Message Content Regardless of whether your app is running in the foreground or background, if you override the onMessageReceived method in the DemoHmsMessageService class, your app can obtain the data message content as long as you send a data message.

Sending a Test Message. Share to. Was this page helpful? Global - English. All rights reserved. Terms of Use. Privacy Policy. Cookie Settings. Try these functions on our mobile app. Intelligent Assistant Chat with our virtual assistant to get answers promptly. Customer Service Submit a ticket to get in touch with our support team. Classic Services Building Standalone Apps. UI Programming. Regulatory Compliance. Technical Specs.

Push Notifications Overview Push Notifications are an important feature, no matter what kind of app you're building. Not only is it nice to let users know about something that may interest them, be it a new album being released, a sale or other limited-time-only deal, or that one of their friends sent them a message, but push notifications are proven to help boost user interaction and create a better overall user experience. Whether you just want to be able to let users know when a relevant event happens, or you're trying to optimize customer engagement and retention, Expo makes implementing push notifications almost too easy.

All the hassle with native device information and communicating with APNs Apple Push Notification service or FCM Firebase Cloud Messaging is taken care of behind the scenes, so that you can treat iOS and Android notifications the same, saving you time on the front-end, and back-end! There are three main steps to setting up push notifications, and we provide a guide for each part of the process:.

The code below shows a full example of how to register for, send, and receive push notifications in an Expo app. But make sure to read the rest of the guide, so that you understand how Expo's push notification service works, what the best practices are, and how to investigate any problems you run into!

We recommend testing push notifications on a physical device. Additionally, when calling Notifications. The Expo push notification tool is also useful for testing push notifications during development.

It lets you easily send test notifications to your device, without having to use your CLI or write out a test server. Next steps. Read through the notification setup guide to get your credentials setup, and start collecting push tokens!

See also. Publish to channel : this publishes a single message to the realtime channel. Subscribe to push channel : this subscribes the device to a channel for push messages. Push messages received on the channel are logged to the activity and logcat. Unsubscribe to push channel : this unsubscribes from the push channel.

Publish data to push channel : this publishes a message to the realtime channel containing data in message. Publish notification to push channel : this publishes a message to the realtime channel containing data in message. Publish notification to push channel from background : this publishes a message to the realtime channel containing data in message.

The resulting message is expected to be delivered as a UI notification. Publish data to push device : this publishes a message direct to the device as a push target containing data in payload.