Scheduled tasks (cronjob-aternative) with Zend framework?

Question

I have a webapplication, written in PHP (Zend Framework) and I'd like to execute a (few) script(s) every once in a while. For example once a day. I know this can be done by using crontab and cronjobs, but not all hostingproviders have these available. Therefor I'm looking for a solution without using the Cronjob.

How do you solve this? What are the possibilities?

It would be interesting to see if there is an alternative, but to my knowledge there is not. — Brian Driscoll, Nov 22 '10 at 17:34
Zend Server (the commercial edition) has a Job Queue that can do recurring tasks. — Gordon, Nov 23 '10 at 08:16

score 4 · Answer 1 · answered Nov 22 '10 at 17:47

4

You could use an service like this:

CronLess

Configure your script to be accessible from outside, and let this service call the url. For security you could protected the script with some kind of token.

answered Nov 22 '10 at 17:47

opHASnoNAME

20,224
26
98
143

We'd like to have it in the application itself, so if the service would stop, our apps would still be usable. Thanks for the suggestion though :-) – koenHuybrechts Nov 22 '10 at 19:17
You dont need such a service. – Elzo Valugi Nov 22 '10 at 20:30

score 4 · Accepted Answer · answered Nov 22 '10 at 20:08

4

Cron jobs really only offer a few basic benefits: scheduling, execution and logging. These are all things that are pretty easy to replicate in a PHP application...

Step One: Create a table of tasks

You'd need to store:

Frequency of execution
What to execute (include file, callback, eval code, etc.)
Calculate next run date
Store previous run dates

Step Two: Execution

You have a few options on how to actually trigger the tasks:

Call a PHP-generated blank GIF image on every page run, which triggers the cron code.
Call an AJAX script which runs the cron code
Call it normally inside your application (may slow execution)

No matter how it starts, it would trigger the actual cron code, which decides whether or not there are any tasks to run, and which ones to run.

Step Three: Logging

This one should be pretty simple. Just log what happens during tasks to a file that you can read after to make sure its working.

...

Before running a task, you'd update the previous run date, and after running a task, you'd set the next run date, based on its frequency. The only fallback of this method is that when nobody visits the sites, no cron jobs will execute until the next visitor comes.

answered Nov 22 '10 at 20:08

Adrian Schneider

7,239
1
19
13

Yep, this is the direction I was going to suggest, but Adrian articulated it much more clearly than I would have. – David Weinraub Nov 23 '10 at 08:13
+0 As you show in Step 2, execution will only take place when some rather unpredictable outside event is triggered. So this solution is only practical when you know you have a constant stream of visitors to your site. A CRON job runs when it's supposed to run. – Gordon Nov 23 '10 at 08:19
This seems to be the right direction :-) THanks a lot for the options!! Option 3 of the execution is out of the question indeed for the possible slow down of the application. – koenHuybrechts Nov 23 '10 at 08:20
@Gordon, what would you suggest that has no dependencies on the environment? Obviously a real cron task is deal, but this is not a bad option when that's not an option. – Adrian Schneider Nov 23 '10 at 17:08
in lack of a real Cron or a JobQueue I'd probably go with a hybrid of yours and ArneRie's solution below, e.g. use a service that triggers the job on my machine in reliable intervals. – Gordon Nov 23 '10 at 19:30

score 1 · Answer 3 · answered Nov 23 '10 at 08:48

Check these links out. I'm currently using a modified bootstrap (based on those articles) on a couple of ZF projects and it's so easy to run the application from the command line.

http://blog.astrumfutura.com/2009/09/the-mysteries-of-asynchronous-processing-with-php-part-1-asynchronous-benefits-task-identification-and-implementation-methods/

http://blog.astrumfutura.com/2009/09/the-mysteries-of-asynchronous-processing-with-php-part-2-making-zend-framework-applications-cli-accessible/

http://blog.astrumfutura.com/2009/10/the-mysteries-of-asynchronous-processing-with-php-part-3-implementation-with-spawned-child-processes-using-simple-scripts-or-zend-framework/

score 0 · Answer 4 · edited May 23 '17 at 12:34

0

I agree with Arne's answer however if you are already using zend framework, you should implement your solution using the built in Zend_Queue which is actually done for that. To see how to implement that here is a link to other question which describes how to set your infrastructure. Infrastructure for Running your Zend Queue Receiver

edited May 23 '17 at 12:34

Community

1
1

answered Mar 06 '13 at 01:39

awavi

837
3
11
23

score 0 · Answer 5 · edited May 23 '17 at 10:33

I have done something similar @Adrian Schneider solution. If you want to add more consistency to your app you can add an interface Cronable that forces the classes that implement it to add a cron() function which will handle the internal logic of the cron, that sometimes is different. All this can be wrapped and called in a similar manner by a cron wrapper which will be the only script called by the cron in the system, which will decide what are the current PHP cron jobs to be executed. You can have some more details in my response from here.

Scheduled tasks (cronjob-aternative) with Zend framework?

5 Answers5