Implementing sending timetout

[rochdi80tn]

For some applications sending emails should be done in a timely manner, for instance when sending a validation code by email.
If for some reasons the sending process is not running mails will remain in the queue until the process() function is called. Which may happen a day later for instance. It would not be practical to send 1 day delayed validation code emails in our case.

I propose, as an enhancement, to add a public attribute to the class to define a timeout. The sending process shall then ignore all pending emails where the sentTime is less than now() - timeout

[rochdi80tn]

Had added this locally by extending the MailQueue class :

class MailQueue extends \nterms\mailqueue\MailQueue {

    public $timeout = 86400; // two days
    
    /**
     * Sends out the messages in email queue and update the database.
     *
     * @return boolean true if all messages are successfully sent out
     */
    public function process() {
        if (Yii::$app->db->getTableSchema($this->table) == null) {
            throw new \yii\base\InvalidConfigException('"' . $this->table . '" not found in database. Make sure the db migration is properly done and the table is created.');
        }

        $success = true;
        
        $items = Queue::find()->where(
            ['and', ['sent_time' => NULL], 
                    ['<', 'attempts', $this->maxAttempts], 
                    ['<=', 'time_to_send', date('Y-m-d H:i:s')],
                    ['>', 'time_to_send', date('Y-m-d H:i:s', time()-$this->timeout)],
            ])->orderBy(['created_at' => SORT_ASC])->limit($this->mailsPerRound);
        ...