The Cloud Functions interface for events that change state, such as Realtime Database or Cloud FirestoreonWrite andonUpdate events.

For more information about the format used to constructChange objects, see below.

Signature:

exportdeclareclassChange<T>

Constructors

Properties

Methods

Change.(constructor)

Constructs a new instance of theChange class

Signature:

constructor(before:T,after:T);

Parameters

Change.after

Signature:

after:T;

Change.before

Signature:

before:T;

Change.fromJSON()

Factory method for creating aChange from JSON and an optional customizer function to be applied to both thebefore and theafter fields.

Signature:

staticfromJSON<T>(json:ChangeJson,customizer?:(x:any)=>T):Change<T>;

Parameters

Returns:

Change<T>

Change.fromObjects()

Factory method for creating aChange from abefore object and anafter object.

Signature:

staticfromObjects<T>(before:T,after:T):Change<T>;

Parameters

Returns:

Change<T>