Hi i'm trying to execute a LONG RUNNING request (action) in background.

function actionRequest($id){

//execute very long process here in background but continue redirect

Yii::app()->user->setFlash('success', "Currently processing your request you may check it from time to time.");
$this->redirect(array('index', 'id'=>$id));
}

What i'm trying to achieve is to NOT have the user waiting for the request to be processed since it generally takes 5-10min, and the request usually goes to a timeout, and even if I set the timeout longer, waiting for 5-10 min. isn't a good user experience.

So I want to return to the page immediately notifying the user that his/her request is being processed, while he can still browse, and do other stuff in the application, he/she can then go back to the page and see that his/her request was processed.

I've looked into Yii extensions backjob, It works, the redirect is executed immediately (somehow a background request), but when doing other things, like navigating in the site, it doesn't load, and it seems that the request is still there, and i cannot continue using the application until the request is finished.

A similar extension runactions promises the same thing, but I could not even get it to work, it says it 'touches a url', like a fire and forget job but doesn't work.

I've also tried to look into message queuing services like Gearman, RabbitMQ, but is really highly technical, I couldn't even install Gearman in my windows machine so "farming" services won't work for me. Some answers to background processing includes CRON and AJAX but that doesn't sound too good, plus a lot of issues.

Is there any other workaround to having asynchronous background processing? I've really sought hard for this, and i'm really not looking for advanced/sophisticated solutions like "farming out work to several machines" and the likes. Thank You very much!

If you want to be able to run asynchronous jobs via Yii, you may not have a choice but to dabble with some AJAX in order to retrieve the status of the job asynchronously. Here are high-level guidelines that worked for me. Hopefully this will assist you in some way!

Setting up a console action

To run background jobs, you will need to use Yii's console component. Under /protected/commands, create a copy of your web controller that has your actionRequest() (e.g. /protected/commands/BulkCommand.php).

This should allow you to go in your /protected folder and run yiic bulk request.

Keep in mind that if you have not created a console application before, you will need to set up its configuration similar to how you've done it for the web application. A straight copy of /protected/config/main.php into /protected/config/console.php should do 90% of the job.

Customizing an extension for running asynchronous console jobs

What has worked for me is using a combination of two extensions: CConsole and TConsoleRunner. TConsoleRunner uses popen to run shell scripts, which worked for me on Windows and Ubuntu. I simply merged its run() code into CConsole as follows:

public function popen($shell, $redirectOutput = '')
{
    $shell = $this->resolveCommandLine($shell, false, $redirectOutput);
    $ret = self::RETURN_CODE_SUCCESS;
    if (!$this->displayCommands) {
        ob_start();
    }

    if ($this->isWindows()) {
        pclose(popen('start /b '.$shell, 'r'));
    }
    else {
        pclose(popen($shell.' > /dev/null &', 'r'));
    }

    if (!$this->displayCommands) {
        ob_end_clean();
    }
    return $ret;
}

protected function isWindows()
{
    if(PHP_OS == 'WINNT' || PHP_OS == 'WIN32')
        return true;
    else 
        return false;
}

Afterwards, I changed CConsole's runCommand() to the following:

public function runCommand($command, $args, $async = false, &$outputLines = null, $executor = 'popen')
    {
        ...
        switch ($executor) {
            ...
            case 'popen':
                return $this->popen($shell);
            ...
        }
    }

Running the asynchronous job

With the above set up, you can now use the following snippet of code to call yiic bulk request we created earlier.

$console = new CConsole();
$console->runCommand('bulk request', array(
    '--arg1="argument"',
    '--arg2="argument"',
    '--arg3="argument"',
));

You would insert this in your original actionRequest().

Checking up on the status

Unfortunately, I'm not sure what kind of work your bulk request is doing. For myself, I was gathering a whole bunch of files and putting them in a folder. I knew going in how many files I expected, so I could easily create a controller action that verifies how many files have been created so far and give a % of the status as a simple division.