An aggregate is a class that decides to record events based on past events.
Creating an aggregate
The easiest way to create an aggregate root would be to use the
php artisan make:aggregate MyAggregate
This will create a class like this:
final class MyAggregate extends AggregateRoot
Retrieving an aggregate
An aggregate can be retrieved like this:
This will cause all events with the given
uuid to be retrieved and fed to the aggregate. For example, an event
MoneyAdded will be passed to the
applyMoneyAdded method on the aggregate if such a method exists.
Inside an aggregate you can record new events using the
recordThat function. All events being passed to that function should implement
Here's an example event
class MoneyAdded extends ShouldBeStored
public function __construct(int $amount)
$this->amount = $amount;
Inside an aggregate root you can pass the event to
public function addMoney(int $amount)
recordThat will not persist the event to the DB, that will happen when the aggregate itself gets persisted. However, recording an event will cause it getting applied to the aggregate immediately. For example, when you record the event
MoneyAdded, we'll immediately call
applyMoneyAdded on the aggregate.
Notice that your event isn't required to contain the
$uuid. Your aggregate is built up for a specific
$uuid and under the hood, the package will save that
$uuid along with the event when the aggregate gets persisted.
To persist an aggregate call
persist on it. Here's an example:
Persisting an aggregate root will write all newly recorded events to the database. The newly persisted events will get passed to all projectors and reactors.