Task Scheduling
Introduction
In the past, developers have generated a Cron entry for each task they need to schedule. However, this is a headache. Your task schedule is no longer in source control, and you must SSH into your server to add the Cron entries. The Laravel command scheduler allows you to fluently and expressively define your command schedule within Laravel itself, and only a single Cron entry is needed on your server.
Your task schedule is defined in the app/Console/Kernel.php
file's schedule
method. To help you get started, a simple example is included with the method. You are free to add as many scheduled tasks as you wish to the Schedule
object.
Starting The Scheduler
Here is the only Cron entry you need to add to your server:
* * * * * php /path/to/artisan schedule:run >> /dev/null >&
This Cron will call the Laravel command scheduler every minute. Then, Laravel evaluates your scheduled tasks and runs the tasks that are due.
Defining Schedules
You may define all of your scheduled tasks in the schedule
method of theApp\Console\Kernel
class. To get started, let's look at an example of scheduling a task. In this example, we will schedule a Closure
to be called every day at midnight. Within the Closure
we will execute a database query to clear a table:
<?php namespace App\Console; use DB;
use Illuminate\Console\Scheduling\Schedule;
use Illuminate\Foundation\Console\Kernel as ConsoleKernel; class Kernel extends ConsoleKernel
{
/**
* The Artisan commands provided by your application.
*
* @var array
*/
protected $commands = [
\App\Console\Commands\Inspire::class,
]; /**
* Define the application's command schedule.
*
* @param \Illuminate\Console\Scheduling\Schedule $schedule
* @return void
*/
protected function schedule(Schedule $schedule)
{
$schedule->call(function () {
DB::table('recent_users')->delete();
})->daily();
}
}
In addition to scheduling Closure
calls, you may also schedule Artisan commands and operating system commands. For example, you may use the command
method to schedule an Artisan command:
$schedule->command('emails:send --force')->daily();
The exec
command may be used to issue a command to the operating system:
$schedule->exec('node /home/forge/script.js')->daily();
Schedule Frequency Options
Of course, there are a variety of schedules you may assign to your task:
Method | Description |
---|---|
->cron('* * * * *'); |
Run the task on a custom Cron schedule |
->everyMinute(); |
Run the task every minute |
->everyFiveMinutes(); |
Run the task every five minutes |
->everyTenMinutes(); |
Run the task every ten minutes |
->everyThirtyMinutes(); |
Run the task every thirty minutes |
->hourly(); |
Run the task every hour |
->daily(); |
Run the task every day at midnight |
->dailyAt('13:00'); |
Run the task every day at 13:00 |
->twiceDaily(1, 13); |
Run the task daily at 1:00 & 13:00 |
->weekly(); |
Run the task every week |
->monthly(); |
Run the task every month |
->yearly(); |
Run the task every year |
These methods may be combined with additional constraints to create even more finely tuned schedules that only run on certain days of the week. For example, to schedule a command to run weekly on Monday:
$schedule->call(function () {
// Runs once a week on Monday at 13:00...
})->weekly()->mondays()->at('13:00');
Below is a list of the additional schedule constraints:
Method | Description |
---|---|
->weekdays(); |
Limit the task to weekdays |
->sundays(); |
Limit the task to Sunday |
->mondays(); |
Limit the task to Monday |
->tuesdays(); |
Limit the task to Tuesday |
->wednesdays(); |
Limit the task to Wednesday |
->thursdays(); |
Limit the task to Thursday |
->fridays(); |
Limit the task to Friday |
->saturdays(); |
Limit the task to Saturday |
->when(Closure); |
Limit the task based on a truth test |
Truth Test Constraints
The when
method may be used to limit the execution of a task based on the result of a given truth test. In other words, if the given Closure
returns true
, the task will execute as long as no other constraining conditions prevent the task from running:
$schedule->command('emails:send')->daily()->when(function () {
return true;
});
When using chained when
methods, the scheduled command will only execute if allwhen
conditions return true
.
Preventing Task Overlaps
By default, scheduled tasks will be run even if the previous instance of the task is still running. To prevent this, you may use the withoutOverlapping
method:
$schedule->command('emails:send')->withoutOverlapping();
In this example, the emails:send
Artisan command will be run every minute if it is not already running. The withoutOverlapping
method is especially useful if you have tasks that vary drastically in their execution time, preventing you from predicting exactly how long a given task will take.
Task Output
The Laravel scheduler provides several convenient methods for working with the output generated by scheduled tasks. First, using the sendOutputTo
method, you may send the output to a file for later inspection:
$schedule->command('emails:send')
->daily()
->sendOutputTo($filePath);
If you would like to append the output to a given file, you may use the appendOutputTo
method:
$schedule->command('emails:send')
->daily()
->appendOutputTo($filePath);
Using the emailOutputTo
method, you may e-mail the output to an e-mail address of your choice. Note that the output must first be sent to a file using the sendOutputTo
method. Also, before e-mailing the output of a task, you should configure Laravel's e-mail services:
$schedule->command('foo')
->daily()
->sendOutputTo($filePath)
->emailOutputTo('foo@example.com');
Note: The
emailOutputTo
andsendOutputTo
methods are exclusive to thecommand
method and are not supported forcall
.
Task Hooks
Using the before
and after
methods, you may specify code to be executed before and after the scheduled task is complete:
$schedule->command('emails:send')
->daily()
->before(function () {
// Task is about to start...
})
->after(function () {
// Task is complete...
});
Pinging URLs
Using the pingBefore
and thenPing
methods, the scheduler can automatically ping a given URL before or after a task is complete. This method is useful for notifying an external service, such as Laravel Envoyer, that your scheduled task is commencing or complete:
$schedule->command('emails:send')
->daily()
->pingBefore($url)
->thenPing($url);
Using either the pingBefore($url)
or thenPing($url)
feature requires the Guzzle HTTP library. You can add Guzzle to your project by adding the following line to yourcomposer.json
file:
"guzzlehttp/guzzle": "~5.3|~6.0"
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