Cron

Job scheduling for Laravel

View the Project on GitHub liebig/cron

Cron

Job scheduling for Laravel

Cron can be used for easily performing cron jobs in Laravel. If you want to run jobs from the internet or just from the local computer, Cron can help you. For more information how Cron can simplify your job scheduling, please have a look at the raison d'être.



Raison d’être

Simplicity

The aim is to create a simple way to define cron jobs with Laravel. Creating cron jobs with Cron is easy because this tool provides you with a lot of events that you can use to manage all your jobs. For creating a job you only need a job name, a cron expression and a function which will be called as soon as the time has come. Of course PHP is only running if you call it, so you need something in addition which starts Cron.

Accessibility

The Cron starting call can be executed from the same machine where your Laravel is located (for example with crontab) or from everywhere on the internet (for example from a web cron service) - it is just a command execution or route call.

Centralization

The Cron management is centralized at a single point in your application. You define all jobs in PHP and don't have to use other tools. Deactivating or removing a Cron job is only a PHP function call away.

Platform independency

Laravel is a great way to build small and big web applications. But not every application platform runs on a server which allows unix shell access. For these applications Cron provides the possibility to use an external web cron service to start Cron. If you have shell access - great, you can make use of Cron's command to start the job management.

Monitoring

If something went wrong with your jobs, Cron will inform you. Next to the logging to Monolog, to the Laravel logging facility and to the database, you can add an event listener to get information about error jobs or successfully executed jobs. After execution you will receive a detailed report about the Cron run. With the power of PHP and events you can send a mail, a notification or anything else if anything happens. Cron is talkative like your grandma.

My personal comfort zone

At last, Cron is my personal way to manage job scheduling. I am a web application developer, not an infrastructure guy. I like to handle things in PHP and not in the shell. I want to deploy my application to another server without worrying if I have access to crontab or other Linux tools. I really like Laravels event functionality but don't like Laravel commands. Cron management should be easy and powerful at the same time. And finally, I love to handle things at a single place in my application without using the shell or write a PHP file for each job. Cron is the try to manage cron jobs without headaches.


Installation

Laravel 5

  1. Add "liebig/cron": "dev-master" to your /path/to/laravel/composer.json file at the "require": section (Find more about composer at http://getcomposer.org/)
  2. Run the composer update liebig/cron --no-dev command in your shell from your /path/to/laravel/ directory
  3. Add 'Liebig\Cron\Laravel5ServiceProvider' to your 'providers' array in the /path/to/laravel/config/app.php file
  4. Migrate the database with running the command php artisan migrate --path=vendor/liebig/cron/src/migrations
  5. Publish the configuration file with running the command php artisan vendor:publish - now you find the Cron configuration file at /path/to/laravel/config/liebigCron.php and this file won't be overwritten at any update
  6. Now you can use Cron everywhere for free

Laravel 4

  1. Add "liebig/cron": "dev-master" to your /path/to/laravel/composer.json file at the "require": section (Find more about composer at http://getcomposer.org/)
  2. Run the composer update liebig/cron --no-dev command in your shell from your /path/to/laravel/ directory
  3. Add 'Liebig\Cron\CronServiceProvider' to your 'providers' array in the /path/to/laravel/app/config/app.php file
  4. Migrate the database with running the command php artisan migrate --package="liebig/cron"
  5. Publish the configuration file with running the command php artisan config:publish liebig/cron - now you find the Cron configuration file at /path/to/laravel/app/config/packages/liebig/cron and this file won't be overwritten at any update
  6. Now you can use Cron everywhere for free

Configuration

Cron is designed to work out of the box without the need of configuration. To enable this a few default values are set. To change Cron's default settings there are two possibilities.

Set methods

You can use the Cron set methods (e.g. setDatabaseLogging, setRunInterval) to change Cron's behaviour. This changes are temporary and the set methods have to be called every time.

Config file

The behaviour values will be loaded from a config file. You can change this values easily by editing in Laravel 5 the /path/to/laravel/app/config/liebigCron.php file and in Laravel 4 the /path/to/laravel/app/config/packages/liebig/cron/config.php file. This is the more permanent way. If you only want to change settings for one run with conditions, we recommend to use the setter methods.

NOTE: All values set via method will overwrite the values loaded from config file.


Example

Cron

If you use Cron's integrated route or command, you only need to listen for the cron.collectJobs event. The best place to do this is in Laravel 5 the /path/to/laravel5/app/Providers/AppServiceProvider.php file at the boot method and in Laravel 4 the /path/to/laravel/app/start/global.php file.

Laravel 5 - AppServiceProvider.php

<?php namespace App\Providers;

use Illuminate\Support\ServiceProvider;

class AppServiceProvider extends ServiceProvider {

    //...

    /**
     * Bootstrap any application services.
     *
     * @return void
     */
    public function boot() {
        // Please note the different namespace
        // and please add a \ in front of your classes in the global namespace
        \Event::listen('cron.collectJobs', function() {

            \Cron::add('example1', '* * * * *', function() {
                // Do some crazy things unsuccessfully every minute
                return 'No';
            });

            \Cron::add('example2', '*/2 * * * *', function() {
                // Do some crazy things successfully every two minute
                return null;
            });

            \Cron::add('disabled job', '0 * * * *', function() {
                // Do some crazy things successfully every hour
            }, false);
        });
    }
}

Laravel 4 - global.php

Event::listen('cron.collectJobs', function() {
    Cron::add('example1', '* * * * *', function() {
                    // Do some crazy things unsuccessfully every minute
                    return 'No';
                });

    Cron::add('example2', '*/2 * * * *', function() {
        // Do some crazy things successfully every two minute
        return null;
    });

    Cron::add('disabled job', '0 * * * *', function() {
        // Do some crazy things successfully every hour
    }, false);
});

Inside the anonymous function you can use all the Laravel and Cron functions. In the next step you have to configure the route or command which will start Cron.

Using Cron's integrated route

If you don't have shell access to your server, you can easily use an online cronjob service (Google knows some good provider). This provider will run Cron's route in a defined interval. The Cron route has to be protected because if someone else than the service provider invokes it, our jobs will be executed too often. For that reason we need a security key in addition to the route path. This key can be generated with the php artisan cron:keygen command call and has to be set in the Cron config file at the key cronKey.

    // Cron application key for securing the integrated Cron run route - if the value is empty, the route is disabled
    'cronKey' => '1PBgabAXdoLTy3JDyi0xRpTR2qNrkkQy'

Now you have to configure the address and run interval at your online cronjob service provider. The address for the integrated Cron route is always http://yourdomain.com/cron.php?key=securitykey. For the above example this address could be http://exampledomain.com/cron.php?key=1PBgabAXdoLTy3JDyi0xRpTR2qNrkkQy and the run interval has to be every minute (due to the job with the name "example1"). Now the jobs were added, the route key was generated and the service provider was configured.

Using Cron's integrated command

If your hosting provider grants you shell access or you can manage cron jobs with a control panel software (e.g. cPanel or Plesk), the best way to run Cron is to use the integrated artisan cron:run command. For the above example the crontab or control panel software command could be * * * * * /usr/bin/php /var/www/laravel/artisan cron:run.

NOTE: If you want to use Cron's in time check, which will test if the time between two Cron run method calls are correct, please configure the key runInterval. In our example we call the route every minute so the value should be 1.


API

Add a cron job

Adding a cron job to Cron is very easy by using the static add function. As parameter the name of the cron job, the cron expression and an anonymous function is needed. The boolean isEnabled is optional and can enable or disable this cron job from execution (default is enabled).

public static function add($name, $expression, $function, $isEnabled = true) {

The name is needed for identifying a cron job if an error appears and for logging.

The expression is a string of five or optional six subexpressions that describe details of the schedule. The syntax is based on the Linux cron daemon definition.

    *    *    *    *    *    *
    -    -    -    -    -    -
    |    |    |    |    |    |
    |    |    |    |    |    + year [optional]
    |    |    |    |    +----- day of week (0 - 7) (Sunday=0 or 7)
    |    |    |    +---------- month (1 - 12)
    |    |    +--------------- day of month (1 - 31)
    |    +-------------------- hour (0 - 23)
    +------------------------- min (0 - 59)

The given anonymous function will be invoked if the expression details match with the current timestamp. This function should return null in the case of success or anything else if there was an error while executing this job. By default, the error case will be logged to the database and to a Monolog logger object (if logger is enabled).

The isEnabled boolean parameter makes it possible to deactivate a job from execution without removing it completely. Later the job execution can be enabled very easily by giving a true boolean to the method. This parameter is optional and the default value is enabled.

Example

\Cron::add('example1', '* * * * *', function() {
                    // Do some crazy things successfully every minute
                    return null;
                });
\Cron::add('example2', '*/2 * * * *', function() {
                    // Oh no, this job has errors and runs every two minutes
                    return false;
                }, true);

Remove a cron job

To remove a set cron job on runtime use the remove method with the cron job name as string parameter.

public static function remove($name) {

Example

\Cron::add('example1', '* * * * *', function() {
                    // Do some crazy things successfully every minute
                    return null;
                });
\Cron::remove('example1');

Enable or disable a cron job

After adding an enabled or disabled cron job ($isEnabled boolean parameter of the add method call) you can disable or enable a cron job by name. For this use the setEnableJob or setDisableJob function.

public static function setEnableJob($jobname, $enable = true) {
public static function setDisableJob($jobname) {

Example

\Cron::add('example1', '* * * * *', function() {
                    // Do some crazy things successfully every minute
                    return null;
                });
\Cron::setDisableJob('example1');
// No jobs will be called
$report = \Cron::run();
\Cron::setEnableJob('example1');
// One job will be called
$report = \Cron::run();

Getter

To receive the enable status boolean of a job, use the static isJobEnabled($jobname) method.


Run the cron jobs

Running the cron jobs is as easy as adding them. Just call the static run method and wait until each added cron job expression is checked. As soon as the time of the expression has come, the corresponding cron job will be invoked. That is the Cron magic. The run method returns a detailed report. By default Cron reckons that you call this method every minute (* * * * *) and by default the report (with their cron jobs errors) will be logged to database. You can change this interval using the setRunInterval function.

public static function run() {

Example

$report = \Cron::run();

NOTE: The run method call has to be the last function call after adding jobs, setting the interval, deactivating database logging and the other function calls.


Set the run interval

The run interval is the time between two cron job route calls. Some cron service provider only supports calls every 15 or even 30 minutes. In this case you have to set this value to 15 or 30. This value is only important to determine if the current run call is in time. If you have disabled database logging in general, you don't have to care about this.

public static function setRunInterval($minutes) {

NOTE: If the route call interval is not every minute you have to adjust your cron job expressions to fit to this interval.

Example

// Set the run intervall to 15 minutes
\Cron::setRunInterval(15);
// Or set the run intervall to 30 minutes
\Cron::setRunInterval(30);

Getter

To recieve the current set run interval use the static getRunInterval() method.


Enable or disable Laravel logging

The Laravel logging facilities provide a layer on top of Monolog. By default, Laravel is configured to create daily log files for your application, and these files are stored in app/storage/logs. Cron will use Laravel logging facilities by default. You can disable this by setting the laravelLogging value to false in the config file or by calling the setLaravelLogging function at runtime.

public static function setLaravelLogging($bool) {

NOTE: You can add a custom Monolog logger to Cron and enable Laravel logging. In this case all messages will be logged to Laravel and to your custom Monolog logger object.

Example

// Laravel logging is enabled by default
\Cron::run();
// Disable Laravel logging
\Cron::setLaravelLogging(false);
// Laravel logging is disabled
\Cron::run();

Getter

To recieve the enabled or disabled boolean value use the static isLaravelLogging() method.


Set a Monolog logger

If you want to add a custom Monolog logger object to Cron use the static setLogger method.

public static function setLogger(\Monolog\Logger $logger = null) {

NOTE: If you want to remove the logger, just call the setLogger method without parameters.

Example

\Cron::setLogger(new \Monolog\Logger('cronLogger'));
// And remove the logger again
\Cron::setLogger();

Getter

To recieve the set logger object use the static getLogger() method. If no logger object is set, null will be returned.


Disable database logging

By default database logging is enabled and after each cron run a manager object and job objects will be saved to database. We strongly recommend to keep the database logging activated because only with this option Cron can check if the current run is in time. It could make sense in some cases to deactivate the database logging with the setDatabaseLogging method.

public static function setDatabaseLogging($bool) {

Example

\Cron::setDatabaseLogging(false);

Getter

To receive the current boolean value of the logging to database variable, just use the static isDatabaseLogging() function.


Log only error jobs to database

By default Cron will log all jobs to database. Maybe sometimes you want to log only error jobs (which not return null) to database by using the static setLogOnlyErrorJobsToDatabase function.

public static function setLogOnlyErrorJobsToDatabase($bool) {

Example

// Log only error jobs to database
\Cron::setLogOnlyErrorJobsToDatabase(true);

Getter

To receive the current boolean value of the error job logging, use the static isLogOnlyErrorJobsToDatabase() function.


Delete old database entries

Cron can delete old database entries for you. During each run method call, Cron checks if there are old manager and job entries in the database and if the reference value is reached, the entries will be deleted. You can change the reference value by calling the setDeleteDatabaseEntriesAfter function. The default value is 240 hours (10 days). To disable the deletion of old entries just set the reference value to 0.

public static function setDeleteDatabaseEntriesAfter($hours) {

Example

// Set the delete database entries reference value to 10 days (24 hours x 10 days)
\Cron::setDeleteDatabaseEntriesAfter(240);

Getter

To receive the current reference value just use the static getDeleteDatabaseEntriesAfter function.


Prevent overlapping

Cron can prevent overlapping. If this is enabled, only one Cron instance can run at the same time. For example if some jobs need 5 minutes for execution but the Cron route will be called every minute, without preventing overlapping two Cron instances will execute jobs at the same time. When running a job twice at the same time, side effects can occur. Cron can avoid such overlaps by using simple locking techniques.

public static function setEnablePreventOverlapping() {

Example

// The configuration could be set via config file with the key 'preventOverlapping' or via method
\Cron::setEnablePreventOverlapping();
// Now the Cron run will only run once at the same time

\Cron::setDisablePreventOverlapping();
// Prevent overlapping is disabled and many Cron run executions are possible at the same time

Getter

To receive the current boolean value just use the static isPreventOverlapping function.

NOTE: To use the overlapping function, Cron needs writing access to the Laravel storage directory. On some Windows machines the lock file cannot be deleted. If you see a delete error message in your log, please disable this feature.


Events

Cron supports Laravel events and provides many information about the run status and the job status. With this you can react to errors. Cron supports the following events.

To subscribe to an event, use Laravels Event facility. The best place for this is the /path/to/laravel/app/start/global.php file.

\Event::listen('cron.jobError', function($name, $return, $runtime, $rundate){
    \Log::error('Job with the name ' . $name . ' returned an error.');
});

Commands

Cron brings you the following Laravel commands.


Reset Cron

To reset the cron management, call the static reset method. It will reset all variables to the default values.

public static function reset() {

Example

\Cron::add('example1', '* * * * *', function() {
                    // Do some crazy things successfully every minute
                    return null;
                });
\Cron::setLogger(new \Monolog\Logger('cronLogger'));
\Cron::reset();
// \Cron::remove('example1') === false
// \Cron::getLogger() === NULL

Frequently Asked Questions

Do I really need crontab or an online cronjob service

Yes, you do. In comparison to a Java application server for example, PHP only runs if it is executed. If crontab or an online cronjob service provider calls PHP and starts the application, Cron can execute the jobs and will start the work. If PHP is not started, the application sleeps and nothing happens.

What is the best interval to call the route or command?

The best interval depends on your jobs. If one job should be executed every minute and another every five minutes, the route or command has to be called every minute. In general you have to find the greatest common divisor of your jobs. Please don't forget to change the runInterval config value if the route or command is not called every minute (default value) and if you want to use Cron's in time check.

Cron is not running properly and returns runtime and inTime with value -1

By default Cron prevents overlapping. This means that only one Cron instance will run at the same time. If another instance is called, Cron will not run and will return the runtime and inTime parameter with the value -1. On some Windows machines the deletion of the lock file fails and you have to disable this feature. Please have a look at the prevent overlapping section.


Changelog

2016/06/07 - 1.1.1

2015/03/02 - 1.1.0

2015/02/02 - 1.0.2

2014/10/13 - 1.0.1

2014/06/12 - 1.0.0

2014/02/11 - v0.9.5

2013/11/12 - v0.9.4

2013/11/01 - v0.9.3


License

The MIT License (MIT)

Copyright (c) 2013 - 2016 Marc Liebig

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

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