php 有限狀態機使用說明
$config = array(
'graph' => 'myGraphA', // Name of the current graph - there can be many of them attached to the same object
'property_path' => 'stateA', // Property path of the object actually holding the state
'states' => array(
'checkout',
'pending',
'confirmed',
'cancelled'
),
'transitions' => array(
'create' => array(
'from' => array('checkout'),
'to' => 'pending'
),
'confirm' => array(
'from' => array('checkout', 'pending'),
'to' => 'confirmed'
),
'cancel' => array(
'from' => array('confirmed'),
'to' => 'cancelled'
)
),
'callbacks' => array(
'guard' => array(
'guard-cancel' => array(
'to' => array('cancelled'), // Will be called only for transitions going to this state
'do' => function() { var_dump('guarding to cancelled state'); return false; }
)
),
'before' => array(
'from-checkout' => array(
'from' => array('checkout'), // Will be called only for transitions coming from this state
'do' => function() { var_dump('from checkout transition'); }
)
),
'after' => array(
'on-confirm' => array(
'on' => array('confirm'), // Will be called only on this transition
'do' => function() { var_dump('on confirm transition'); }
),
'to-cancelled' => array(
'to' => array('cancelled'), // Will be called only for transitions going to this state
'do' => function() { var_dump('to cancel transition'); }
),
'cancel-date' => array(
'to' => array('cancelled'),
'do' => array('object', 'setCancelled'),
),
)
)
);各個屬性說明
1'property_path' => 'stateA'
需要在 DomainObject物件中定義，如：
class DomainObject
{
private $stateA = 'checkout';//初始狀態
public function getStateA()
{
return $this->stateA;
}
public function setStateA($state)
{
$this->stateA = $state;
}
}2 states
定義所有可能的狀態
'states' => array(
'checkout',
'pending',
'confirmed',
'cancelled'
),3 transitions
定義了執行動作後的狀態變化
'transitions' => array(
'create' => array(
'from' => array('checkout'),
'to' => 'pending'
),
'confirm' => array(
'from' => array('checkout', 'pending'),
'to' => 'confirmed'
),
'cancel' => array(
'from' => array('confirmed'),
'to' => 'cancelled'
)
),4 callbacks
定義了什麼時候執行相對應的回撥
'callbacks' => array(
'guard' => array(
'guard-cancel' => array(
'to' => array('cancelled'), // Will be called only for transitions going to this state
'do' => function() { var_dump('guarding to cancelled state'); return false; }
)
),
'before' => array(
'from-checkout' => array(
'from' => array('checkout'), // Will be called only for transitions coming from this state
'do' => function() { var_dump('from checkout transition'); }
)
),
'after' => array(
'on-confirm' => array(
'on' => array('confirm'), // Will be called only on this transition
'do' => function() { var_dump('on confirm transition'); }
),
'to-cancelled' => array(
'to' => array('cancelled'), // Will be called only for transitions going to this state
'do' => function() { var_dump('to cancel transition'); }
),
'cancel-date' => array(
'to' => array('cancelled'),
'do' => array('object', 'setCancelled'),
),
)
)下面這個定義了是否可以更改到當前狀態，guard-cancel修飾作用沒有實際意義，執行的時候會掃描整個陣列，當to的指向狀態是cancelled時執行do回撥，當回撥返回true的時候可以更改到該狀態，類似於中介軟體
'guard' => array(
'guard-cancel' => array(
'to' => array('cancelled'), // Will be called only for transitions going to this state
'do' => function() { var_dump('guarding to cancelled state'); return false; }
)
),透過guard之後會先執行before,陣列的key其修飾作用，執行的時候會迴圈這個陣列，當from的狀態是checkout會執行do回撥，
'before' => array(
'from-checkout' => array(
'from' => array('checkout'), // Will be called only for transitions coming from this state
'do' => function() { var_dump('from checkout transition'); }
)
),before執行完之後，接下來開始掃描after陣列，其key起裝飾作用。有兩種型別一種是on do,另一種是to do 。on 對應的是transitions的key值，匹配到此key值就執行do回撥。to對應的是要轉換到的狀態，匹配到此狀態就執行do回撥
'after' => array(
'on-confirm' => array(
'on' => array('confirm'), // Will be called only on this transition
'do' => function() { var_dump('on confirm transition'); }
),
'to-cancelled' => array(
'to' => array('cancelled'), // Will be called only for transitions going to this state
'do' => function() { var_dump('to cancel transition'); }
),
'cancel-date' => array(
'to' => array('cancelled'),
'do' => array('object', 'setCancelled'),
),
)do回撥有兩種方式一種是回撥，另一種是DomainObject的方法
'do' => array('object', 'setCancelled'),對應
class DomainObject
{
private $stateA = 'checkout';//初始狀態
public function getStateA()
{
return $this->stateA;
}
public function setStateA($state)
{
$this->stateA = $state;
}
public function setConfirmedNow()
{
var_dump('I (the object) am set confirmed at '.date('Y-m-d').'.');
}
}的setConfirmedNow方法
有三個事件
const PRE_TRANSITION = 'winzou.state_machine.pre_transition';
const POST_TRANSITION = 'winzou.state_machine.post_transition';
const TEST_TRANSITION = 'winzou.state_machine.test_transition';定義完圖後，設定一個初始狀態，例如把訂單的checkout狀態設定進去DomainObject中，然後操作執行相對應的方法（\$stateMachine->apply('create')），可能執行成功（$stateMachine->getState()，設定狀態進入訂單表），也可能執行不成功（錯誤處理），
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