Properties

collapseKey

string

String identifying a group of messages (for example, "Updates Available") that can be collapsed, so that only the last message gets sent when delivery can be resumed. This is used to avoid sending too many of the same messages when the device comes back online or becomes active.

There is no guarantee of the order in which messages get sent.

A maximum of four different collapse keys is allowed at any given time. This means an FCM connection server can simultaneously store four different send-to-sync messages per client app. If you exceed this number, there is no guarantee which four collapse keys the FCM connection server will keep.

Default value: None

contentAvailable

boolean

On iOS, use this field to represent content-available in the APNs payload. When a notification or data message is sent and this is set to true, an inactive client app is awoken. On Android, data messages wake the app by default. On Chrome, this flag is currently not supported.

Default value: false

dryRun

boolean

Whether or not the message should actually be sent. When set to true, allows developers to test a request without actually sending a message. When set to false, the message will be sent.

Default value: false

mutableContent

boolean

On iOS, use this field to represent mutable-content in the APNs payload. When a notification is sent and this is set to true, the content of the notification can be modified before it is displayed, using a Notification Service app extension

On Android and Web, this parameter will be ignored.

Default value: false

priority

string

The priority of the message. Valid values are "normal" and "high". On iOS, these correspond to APNs priorities 5 and 10.

By default, notification messages are sent with high priority, and data messages are sent with normal priority. Normal priority optimizes the client app's battery consumption and should be used unless immediate delivery is required. For messages with normal priority, the app may receive the message with unspecified delay.

When a message is sent with high priority, it is sent immediately, and the app can wake a sleeping device and open a network connection to your server.

For more information, see Setting the priority of a message.

Default value: "high" for notification messages, "normal" for data messages

restrictedPackageName

string

The package name of the application which the registration tokens must match in order to receive the message.

Default value: None

timeToLive

number

How long (in seconds) the message should be kept in FCM storage if the device is offline. The maximum time to live supported is four weeks, and the default value is also four weeks. For more information, see Setting the lifespan of a message.

Default value: 2419200 (representing four weeks, in seconds)