PHPyii2 Queue Shmilyzxt/yii2-queue Introduction

• In the use of the process feel very good, it is recommended to look at the principle of the queue.

• shmilyzxt/yii2-queueSimple explanation:

1. I use the YII2 Premium version, we start from the configuration to see the code, here I use the MySQL queue, the first configuration file, I put the queue configuration item in the root directory under common\config\main-local.php the components array, change the database configuration. Replication composer after installation
   vendor\shmilyzxt\yii2-queue\jobs\jobs.sql
vendor\shmilyzxt\yii2-queue\failed\failed.sql
   2 SQL files into the database to set up the queue data table and the data table when the task fails to execute.

2. Push task start syntax: \Yii::$app->queue->pushOn(new SendMial(),['email'=>'49783121@qq.com','title'=>'test','content'=>'email test'],'email'); let's vendor\shmilyzxt\queue\queues\DatabaseQueue.php go to see the code, which is pushOn() written in the DatabaseQueue class's parent class vendor\shmilyzxt\queue\base\Queue.php :

into the queue public function Pushon ($job, $data = ", $queue = null)    {        //canpush checks if the queue has reached the maximum task amount        if ($this->canpush ()) {              //beforepush event            $this->trigger (Self::event_before_push) before entering the queue;             into            the queue $ret = $this->push ($job, $data, $queue);            Afterpush Event            $this->trigger (Self::event_after_push) after entering the queue;            return $ret;        } else {            throw new \exception ("Max jobs number exceed! The max jobs number is {$this->maxjob} ");        }    }

Note: It's a good idea to look at the Yii2 event class.

About into the queue: $this->push($job, $data, $queue); , here in the matching queue class file view, related functions jump, processing the data record into the database. Function direction: getQueue()-->createPayload()-->pushToDatabase() ), the result of the pushOn() final return data inserted into the database, the success $ret is 1.

3. Background Run command processing queue, example: php ./yii worker/listen default 10 128 3 0 where default is the name of the queue, the above pushes a email queue should be changed email .
After starting the command, let's look at the code: first execute: The WorkerController controller actionListen method, we follow the code into the vendor\shmilyzxt\queue\Worker.php -- listen method, here is actually always in the loop, the task of performing the operation queue:

/** * Enable a queue background listener task * @param queue $queue * @param string $queueName The name of the listener queue (the queue to which to push the task when Pushon, you need to listen to the queue to get the task) * @param int $attempt Queue task failed attempts, 0 is unlimited * @param int $memory maximum memory allowed * @param int $sleep time interval per detection */public STA                Tic function Listen (Queue $queue, $queueName = ' Default ', $attempt = ten, $memory =, $sleep = 3, $delay = 0) {                while (true) {try{//databasequeue removes an available task (instance) from the database queue and updates the task             $job = $queue->pop ($queueName);                }catch (\exception $e) {throw $e;             Continue                 if ($job instanceof Job) {//To determine if the number of execution errors is greater than the number of executions passed in if ($attempt > 0 && $job->getattempts () > $attempt) {$job->fail                 Ed ();                                  }else{try{               throw new \exception ("Test Failed");                      $job->execute (); }catch (\exception $e) {//execution failed, judging whether it was deleted, re-queued if ( !                          $job->isdeleted ()) {$job->release ($delay); }}}}else{Self::sleep ($                Sleep);                } if (self::memoryexceeded ($memory)) {self::stop (); }               }    }

Note: $queue->pop($queueName); vendor\shmilyzxt\queue\queues\DatabaseQueue.php executing SQL using transactions within a method, and creating vendor\shmilyzxt\queue\jobs\DatabaseJob.php an instance

//Remove a task public function pop ($queue = null) {$queue = $this->ge        Tqueue ($queue);        if (!is_null ($this->expire)) {//$this->releasejobsthathavebeenreservedtoolong ($queue);        } $tran = $this->connector->begintransaction (); Determine if there is an available task that needs to execute if ($job = $this->getnextavailablejob ($queue)) {$this->markjobasreserved ($job-            >ID);            $tran->commit ();                $config = Array_merge ($this->jobevent, [' class ' = ' Shmilyzxt\queue\jobs\databasejob ',            ' Queue ' = $queue, ' job ' = $job, ' queueinstance ' + $this,]);        Return \yii::createobject ($config);        } $tran->commit ();    return false; }

As for: $job->execute(); is DatabaseJob inherited Job from the parent class execution, along with the code to find out is yii\base\Component trigger the execution of the event,

/**  * Perform task  */public function execute () {     //beforeexecute an event before performing a task there is no executable code in jobevent  $this- >trigger (Self::event_before_execute, New Jobevent ("job" = $this, ' payload ' + $this->getpayload ()]));  $this->resolveandfire ();//method of the task actually performed}

 /** * True Task execution method (call hander's Handle method) * @param array $payload * @return void */protected function Resolveandfire ()        {$payload = $this->getpayload (); $payload = Unserialize ($payload);        Deserialization of data $type = $payload [' type '];        $class = $payload [' Job '];                        if ($type = = ' closure ' && ($closure = (new Serializer ())->unserialize ($class [1])) instanceof \closure) {            $this->handler = $this->gethander ($class [0]);            $this->handler->closure = $closure;        $this->handler->handle ($this, $payload [' data '];        } else if ($type = = ' Classmethod ') {$payload [' job '][0]-> $payload [' Job '][1] ($this, $payload [' data ']);        } else if ($type = = ' Staticmethod ') {$payload [' job '][0]:: $payload [' Job '][1] ($this, $payload [' data ']);            } else {//execute ' handle ($job, $data) ' method of ' SendMail ' class $this->handler = $this->gethander ($class); $this->handler->handlE ($this, $payload [' data ']);        }//Delete if after executing task (! $this->isdeletedorreleased ()) {$this->delete (); }    }

Finally to the SendMail class of execution handle($job,$data) , here is the object and data pushed to the queue, and then our processing logic.

Public function handle ($job, $data)    {        if ($job->getattempts () > 3) {            $this->failed ($job);        }        $payload = $job->getpayload ();        Echo ' <pre> ';p rint_r ($payload);        $payload is the task data, you get the task data will be able to execute e-mail//todo e-        Mail    }