Merge pull request #24 from VeerUP/without-overlapping

Without overlapping

CallbackEvent.php

@@ -4,6 +4,7 @@
 use Yii;
 use yii\base\Application;
 use yii\base\InvalidParamException;
+use yii\mutex\Mutex;
 
 /**
  * Class CallbackEvent
@@ -24,14 +25,19 @@ class CallbackEvent extends Event
     protected $parameters;
 
     /**
+     * Create a new event instance.
+     *
+     * @param Mutex $mutex
      * @param string $callback
      * @param array $parameters
      * @param array $config
+     * @throws InvalidParamException
      */
-    public function __construct($callback, array $parameters = [], $config = [])
+    public function __construct(Mutex $mutex, $callback, array $parameters = [], $config = [])
     {
         $this->callback = $callback;
         $this->parameters = $parameters;
+        $this->_mutex = $mutex;
 
         if (!empty($config)) {
             Yii::configure($this, $config);
@@ -59,6 +65,34 @@ public function run(Application $app)
         $this->trigger(self::EVENT_AFTER_RUN);
         return $response;
     }
+
+    /**
+     * Do not allow the event to overlap each other.
+     *
+     * @return $this
+     * @throws InvalidParamException
+     */
+    public function withoutOverlapping()
+    {
+        if (empty($this->_description)) {
+            throw new InvalidParamException(
+                "A scheduled event name is required to prevent overlapping. Use the 'description' method before 'withoutOverlapping'."
+            );
+        }
+
+        return parent::withoutOverlapping();
+    }
+
+    /**
+     * Get the mutex name for the scheduled command.
+     *
+     * @return string
+     */
+    protected function mutexName()
+    {
+        return 'framework/schedule-' . sha1($this->_description);
+    }
+
     /**
      * Get the summary of the event for display.
      *

Event.php

@@ -9,6 +9,7 @@
 use yii\base\Component;
 use yii\base\InvalidCallException;
 use yii\mail\MailerInterface;
+use yii\mutex\Mutex;
 
 
 /**
@@ -72,16 +73,24 @@ class Event extends Component
      * @var string
      */
     protected $_description;
+    /**
+     * The mutex implementation.
+     *
+     * @var \yii\mutex\Mutex
+     */
+    protected $_mutex;
 
     /**
      * Create a new event instance.
      *
+     * @param Mutex $mutex
      * @param string $command
      * @param array $config
      */
-    public function __construct($command, $config = [])
+    public function __construct(Mutex $mutex, $command, $config = [])
     {
         $this->command = $command;
+        $this->_mutex = $mutex;
         $this->_output = $this->getDefaultOutput();
         parent::__construct($config);
     }
@@ -101,6 +110,16 @@ public function run(Application $app)
         $this->trigger(self::EVENT_AFTER_RUN);
     }
 
+    /**
+     * Get the mutex name for the scheduled command.
+     *
+     * @return string
+     */
+    protected function mutexName()
+    {
+        return 'framework/schedule-' . sha1($this->_expression . $this->command);
+    }
+
     /**
      * Run the command in the foreground.
      *
@@ -479,6 +498,20 @@ public function user($user)
         return $this;
     }
 
+    /**
+     * Do not allow the event to overlap each other.
+     *
+     * @return $this
+     */
+    public function withoutOverlapping()
+    {
+        return $this->then(function() {
+            $this->_mutex->release($this->mutexName());
+        })->skip(function() {
+            return !$this->_mutex->acquire($this->mutexName());
+        });
+    }
+
     /**
      * Register a callback to further filter the schedule.
      *

README.md

@@ -1,7 +1,7 @@
 Schedule extension for Yii2
 ===========================
 
-This extension is the port of Laravel's Schedule component (http://laravel.com/docs/master/artisan#scheduling-artisan-commands)
+This extension is the port of Laravel's Schedule component (https://laravel.com/docs/master/scheduling#scheduling-artisan-commands)
 
 Installation
 ------------
@@ -146,6 +146,13 @@ $schedule->command('foo')->monthly()->when(function()
 $schedule->command('foo')->sendOutputTo($filePath)->emailOutputTo('foo@example.com');
 ```
 
+**Preventing Task Overlaps**
+
+```php
+$schedule->command('foo')->withoutOverlapping();
+```
+Used by default yii\mutex\FileMutex or 'mutex' application component (http://www.yiiframework.com/doc-2.0/yii-mutex-mutex.html)
+
 How to use this extension in your application?
 ----------------------------------------------
 

Schedule.php

@@ -1,8 +1,11 @@
 <?php
 
 namespace omnilight\scheduling;
+
+use Yii;
 use yii\base\Component;
 use yii\base\Application;
+use yii\mutex\FileMutex;
 
 
 /**
@@ -17,11 +20,29 @@ class Schedule extends Component
      */
     protected $_events = [];
 
+    /**
+     * The mutex implementation.
+     *
+     * @var \yii\mutex\Mutex
+     */
+    protected $_mutex;
+
     /**
      * @var string The name of cli script
      */
     public $cliScriptName = 'yii';
 
+    /**
+     * Schedule constructor.
+     * @param array $config
+     */
+    public function __construct(array $config = [])
+    {
+        $this->_mutex = Yii::$app->has('mutex') ? Yii::$app->get('mutex') : (new FileMutex());
+
+        parent::__construct($config);
+    }
+
     /**
      * Add a new callback event to the schedule.
      *
@@ -31,7 +52,7 @@ class Schedule extends Component
      */
     public function call($callback, array $parameters = array())
     {
-        $this->_events[] = $event = new CallbackEvent($callback, $parameters);
+        $this->_events[] = $event = new CallbackEvent($this->_mutex, $callback, $parameters);
         return $event;
     }
     /**
@@ -53,7 +74,7 @@ public function command($command)
      */
     public function exec($command)
     {
-        $this->_events[] = $event = new Event($command);
+        $this->_events[] = $event = new Event($this->_mutex, $command);
         return $event;
     }