FirebaseInstanceId

public class FirebaseInstanceId extends Object

Firebase Instance ID provides a unique identifier for each app instance and a mechanism to authenticate and authorize actions (example: sending FCM messages).

Instance ID is stable except when:

  • App deletes Instance ID
  • App is restored on a new device
  • User uninstalls/reinstall the app
  • User clears app data
In the above cases a new Instance ID is generated and the application needs to recreate the authorization tokens previously generated implementing onTokenRefresh().

Once an Instance ID is generated, the library periodically sends information about the application and the device where it's running to the Firebase backend. To stop this, see deleteInstanceId().

To prove ownership of Instance ID and to allow servers to access data or services associated with the app, call getToken(String, String).

Public Method Summary

void
deleteInstanceId()
Delete the Instance ID and the data associated with it.
void
deleteToken(String authorizedEntity, String scope)
Revokes access to a scope (action) for an entity previously authorized by getToken().
long
getCreationTime()
Returns time when instance ID was created.
String
getId()
Returns a stable identifier that uniquely identifies the app instance.
static FirebaseInstanceId
getInstance()
Returns an instance of this class.
synchronized static FirebaseInstanceId
getInstance(FirebaseApp app)
Returns an instance for the given FirebaseApp.
Task<InstanceIdResult>
getInstanceId()
Returns the ID and automatically generated token for this Firebase project.
String
getToken(String authorizedEntity, String scope)
Returns a token that authorizes an Entity to perform an action on behalf of the application identified by Instance ID.
String
getToken()
This method was deprecated. In favour of getInstanceId().

Inherited Method Summary

Public Methods

public void deleteInstanceId ()

Delete the Instance ID and the data associated with it.

This stops the periodic sending of data to the Firebase backend started when the Instance ID was generated, unless another library that requires InstanceId (like FCM, RemoteConfig or Analytics) is used or it's configured to be executed automatically.

A new Instance ID is generated asynchronously if Firebase Cloud Messaging auto-init is enabled.

This is a blocking function so do not call it on the main thread.

Throws
IOException

public void deleteToken (String authorizedEntity, String scope)

Revokes access to a scope (action) for an entity previously authorized by getToken().

This is a blocking function so do not call it on the main thread.

Parameters
authorizedEntity Entity that must no longer have access.
scope Action that entity is no longer authorized to perform.
Throws
IOException if the request fails.

public long getCreationTime ()

Returns time when instance ID was created.

Returns
  • Time when instance ID was created (milliseconds since Epoch).

public String getId ()

Returns a stable identifier that uniquely identifies the app instance.

Once an Instance ID is generated, the library periodically sends information about the application and the device where it's running to the Firebase backend. To stop this, see deleteInstanceId().

Returns
  • The identifier for the application instance.

public static FirebaseInstanceId getInstance ()

Returns an instance of this class.

Returns
  • FirebaseInstanceId instance.

public static synchronized FirebaseInstanceId getInstance (FirebaseApp app)

Returns an instance for the given FirebaseApp.

Parameters
app FirebaseApp instance.
Returns
  • FirebaseInstanceId instance.

public Task<InstanceIdResult> getInstanceId ()

Returns the ID and automatically generated token for this Firebase project.

This generates an Instance ID if it does not exist yet, which starts periodically sending information to the Firebase backend (see getId()).

Returns

public String getToken (String authorizedEntity, String scope)

Returns a token that authorizes an Entity to perform an action on behalf of the application identified by Instance ID.

This generates an Instance ID if it does not exist yet, which starts periodically sending information to the Firebase backend (see getId()).

This is similar to an OAuth2 token except, it applies to the application instance instead of a user.

For example, to get a token that can be used to send messages to an application via FirebaseMessaging, set authorizedEntity to the sender ID, and set scope to "FCM".

This is a blocking function so do not call it on the main thread.

Parameters
authorizedEntity Entity authorized by the token.
scope Action authorized for authorizedEntity.
Returns
  • a token that can identify and authorize the instance of the application on the device.
Throws
IOException if the request fails.

public String getToken ()

This method was deprecated.
In favour of getInstanceId().

Returns the automatically generated token for the default Firebase project.

This generates an Instance ID if it does not exist yet, which starts periodically sending information to the Firebase backend (see getId()).

Returns
  • the master token or null if the token is not yet available