The timestamp behavior allows your table objects to update one or more
timestamps on each model event. This is primarily used to populate data into
created
and modified
fields. However, with some additional
configuration, you can update any timestamp/datetime column on any event a table
publishes.
You enable the timestamp behavior like any other behavior:
class ArticlesTable extends Table
{
public function initialize(array $config)
{
$this->addBehavior('Timestamp');
}
}
The default configuration will do the following:
When a new entity is saved the created
and modified
fields will be set
to the current time.
When an entity is updated, the modified
field is set to the current time.
If you need to modify fields with different names, or want to update additional timestamp fields on custom events you can use some additional configuration:
class OrdersTable extends Table
{
public function initialize(array $config)
{
$this->addBehavior('Timestamp', [
'events' => [
'Model.beforeSave' => [
'created_at' => 'new',
'updated_at' => 'always',
],
'Orders.completed' => [
'completed_at' => 'always'
]
]
]);
}
}
As you can see above, in addition to the standard Model.beforeSave
event, we
are also updating the completed_at
column when orders are completed.
Sometimes you’ll want to update just the timestamps on an entity without
changing any other properties. This is sometimes referred to as ‘touching’
a record. In CakePHP you can use the touch()
method to do exactly this:
// Touch based on the Model.beforeSave event.
$articles->touch($article);
// Touch based on a specific event.
$orders->touch($order, 'Orders.completed');
After you have saved the entity, the field is updated.
Touching records can be useful when you want to signal that a parent resource has changed when a child resource is created/updated. For example: updating an article when a new comment is added.
To disable the automatic modification of the updated
timestamp column when
saving an entity you can mark the attribute as ‘dirty’:
// Mark the modified column as dirty making
// the current value be set on update.
$order->setDirty('modified', true);
// Prior to 3.4.0
$order->dirty('modified', true);