Queues
Introduction
While building your web application, you may have some tasks, such as parsing and storing an uploaded CSV file, that take too long to perform during a typical web request. Thankfully, Laravel allows you to easily create queued jobs that may be processed in the background. By moving time intensive tasks to a queue, your application can respond to web requests with blazing speed and provide a better user experience to your customers.
Laravel queues provide a unified queueing API across a variety of different queue backends, such as Amazon SQS, Redis, or even a relational database.
Laravel's queue configuration options are stored in your application's config/queue.php
configuration file. In this file, you will find connection configurations for each of the queue drivers that are included with the framework, including the database, Amazon SQS, Redis, and Beanstalkd drivers, as well as a synchronous driver that will execute jobs immediately (for use during local development). A null
queue driver is also included which discards queued jobs.
Laravel now offers Horizon, a beautiful dashboard and configuration system for your Redis powered queues. Check out the full Horizon documentation for more information.
Connections Vs. Queues
Before getting started with Laravel queues, it is important to understand the distinction between "connections" and "queues". In your config/queue.php
configuration file, there is a connections
configuration array. This option defines the connections to backend queue services such as Amazon SQS, Beanstalk, or Redis. However, any given queue connection may have multiple "queues" which may be thought of as different stacks or piles of queued jobs.
Note that each connection configuration example in the queue
configuration file contains a queue
attribute. This is the default queue that jobs will be dispatched to when they are sent to a given connection. In other words, if you dispatch a job without explicitly defining which queue it should be dispatched to, the job will be placed on the queue that is defined in the queue
attribute of the connection configuration:
use App\Jobs\ProcessPodcast;
// This job is sent to the default connection's default queue...
ProcessPodcast::dispatch();
// This job is sent to the default connection's "emails" queue...
ProcessPodcast::dispatch()->onQueue('emails');
Some applications may not need to ever push jobs onto multiple queues, instead preferring to have one simple queue. However, pushing jobs to multiple queues can be especially useful for applications that wish to prioritize or segment how jobs are processed, since the Laravel queue worker allows you to specify which queues it should process by priority. For example, if you push jobs to a high
queue, you may run a worker that gives them higher processing priority:
php artisan queue:work --queue=high,default
Driver Notes & Prerequisites
Database
In order to use the database
queue driver, you will need a database table to hold the jobs. To generate a migration that creates this table, run the queue:table
Artisan command. Once the migration has been created, you may migrate your database using the migrate
command:
php artisan queue:table
php artisan migrate
Finally, don't forget to instruct your application to use the database
driver by updating the QUEUE_CONNECTION
variable in your application's .env
file:
QUEUE_CONNECTION=database
Redis
In order to use the redis
queue driver, you should configure a Redis database connection in your config/database.php
configuration file.
Redis Cluster
If your Redis queue connection uses a Redis Cluster, your queue names must contain a key hash tag. This is required in order to ensure all of the Redis keys for a given queue are placed into the same hash slot:
'redis' => [
'driver' => 'redis',
'connection' => 'default',
'queue' => '{default}',
'retry_after' => 90,
],
Blocking
When using the Redis queue, you may use the block_for
configuration option to specify how long the driver should wait for a job to become available before iterating through the worker loop and re-polling the Redis database.
Adjusting this value based on your queue load can be more efficient than continually polling the Redis database for new jobs. For instance, you may set the value to 5
to indicate that the driver should block for five seconds while waiting for a job to become available:
'redis' => [
'driver' => 'redis',
'connection' => 'default',
'queue' => 'default',
'retry_after' => 90,
'block_for' => 5,
],
Setting block_for
to 0
will cause queue workers to block indefinitely until a job is available. This will also prevent signals such as SIGTERM
from being handled until the next job has been processed.
Other Driver Prerequisites
The following dependencies are needed for the listed queue drivers. These dependencies may be installed via the Composer package manager:
- Amazon SQS:
aws/aws-sdk-php ~3.0
- Beanstalkd:
pda/pheanstalk ~4.0
- Redis:
predis/predis ~1.0
or phpredis PHP extension
Creating Jobs
Generating Job Classes
By default, all of the queueable jobs for your application are stored in the app/Jobs
directory. If the app/Jobs
directory doesn't exist, it will be created when you run the make:job
Artisan command:
php artisan make:job ProcessPodcast
The generated class will implement the Illuminate\Contracts\Queue\ShouldQueue
interface, indicating to Laravel that the job should be pushed onto the queue to run asynchronously.
Job stubs may be customized using stub publishing.
Class Structure
Job classes are very simple, normally containing only a handle
method that is invoked when the job is processed by the queue. To get started, let's take a look at an example job class. In this example, we'll pretend we manage a podcast publishing service and need to process the uploaded podcast files before they are published:
<?php
namespace App\Jobs;
use App\Models\Podcast;
use App\Services\AudioProcessor;
use Illuminate\Bus\Queueable;
use Illuminate\Contracts\Queue\ShouldQueue;
use Illuminate\Foundation\Bus\Dispatchable;
use Illuminate\Queue\InteractsWithQueue;
use Illuminate\Queue\SerializesModels;
class ProcessPodcast implements ShouldQueue
{
use Dispatchable, InteractsWithQueue, Queueable, SerializesModels;
/**
* The podcast instance.
*
* @var \App\Models\Podcast
*/
protected $podcast;
/**
* Create a new job instance.
*
* @param App\Models\Podcast $podcast
* @return void
*/
public function __construct(Podcast $podcast)
{
$this->podcast = $podcast;
}
/**
* Execute the job.
*
* @param App\Services\AudioProcessor $processor
* @return void
*/
public function handle(AudioProcessor $processor)
{
// Process uploaded podcast...
}
}
In this example, note that we were able to pass an Eloquent model directly into the queued job's constructor. Because of the SerializesModels
trait that the job is using, Eloquent models and their loaded relationships will be gracefully serialized and unserialized when the job is processing.
If your queued job accepts an Eloquent model in its constructor, only the identifier for the model will be serialized onto the queue. When the job is actually handled, the queue system will automatically re-retrieve the full model instance and its loaded relationships from the database. This approach to model serialization allows for much smaller job payloads to be sent to your queue driver.
handle
Method Dependency Injection
The handle
method is invoked when the job is processed by the queue. Note that we are able to type-hint dependencies on the handle
method of the job. The Laravel service container automatically injects these dependencies.
If you would like to take total control over how the container injects dependencies into the handle
method, you may use the container's bindMethod
method. The bindMethod
method accepts a callback which receives the job and the container. Within the callback, you are free to invoke the handle
method however you wish. Typically, you should call this method from the boot
method of your App\Providers\AppServiceProvider
service provider:
use App\Jobs\ProcessPodcast;
use App\Services\AudioProcessor;
$this->app->bindMethod([ProcessPodcast::class, 'handle'], function ($job, $app) {
return $job->handle($app->make(AudioProcessor::class));
});
Binary data, such as raw image contents, should be passed through the base64_encode
function before being passed to a queued job. Otherwise, the job may not properly serialize to JSON when being placed on the queue.
Queued Relationships
Because loaded relationships also get serialized, the serialized job string can sometimes become quite large. To prevent relations from being serialized, you can call the withoutRelations
method on the model when setting a property value. This method will return an instance of the model without its loaded relationships:
/**
* Create a new job instance.
*
* @param \App\Models\Podcast $podcast
* @return void
*/
public function __construct(Podcast $podcast)
{
$this->podcast = $podcast->withoutRelations();
}
Furthermore, when a job is deserialized and model relationships are re-retrieved from the database, they will be retrieved in their entirety. Any previous relationship constraints that were applied before the model was serialized during the job queueing process will not be applied when the job is deserialized. Therefore, if you wish to work with a subset of a given relationship, you should re-constrain that relationship within your queued job.
Unique Jobs
Unique jobs require a cache driver that supports locks. Currently, the memcached
, redis
, dynamodb
, database
, file
, and array
cache drivers support atomic locks. In addition, unique job constraints do not apply to jobs within batches.
Sometimes, you may want to ensure that only one instance of a specific job is on the queue at any point in time. You may do so by implementing the ShouldBeUnique
interface on your job class. This interface does not require you to define any additional methods on your class:
<?php
use Illuminate\Contracts\Queue\ShouldQueue;
use Illuminate\Contracts\Queue\ShouldBeUnique;
class UpdateSearchIndex implements ShouldQueue, ShouldBeUnique
{
...
}
In the example above, the UpdateSearchIndex
job is unique. So, the job will not be dispatched if another instance of the job is already on the queue and has not finished processing.
In certain cases, you may want to define a specific "key" that makes the job unique or you may want to specify a timeout beyond which the job no longer stays unique. To accomplish this, you may define uniqueId
and uniqueFor
properties or methods on your job class:
<?php
use App\Models\Product;
use Illuminate\Contracts\Queue\ShouldQueue;
use Illuminate\Contracts\Queue\ShouldBeUnique;
class UpdateSearchIndex implements ShouldQueue, ShouldBeUnique
{
/**
* The product instance.
*
* @var \App\Product
*/
public $product;
/**
* The number of seconds after which the job's unique lock will be released.
*
* @var int
*/
public $uniqueFor = 3600;
/**
* The unique ID of the job.
*
* @return string
*/
public function uniqueId()
{
return $this->product->id;
}
}
In the example above, the UpdateSearchIndex
job is unique by a product ID. So, any new dispatches of the job with the same product ID will be ignored until the existing job has completed processing. In addition, if the existing job is not processed within one hour, the unique lock will be released and another job with the same unique key can be dispatched to the queue.
Keeping Jobs Unique Until Processing Begins
By default, unique jobs are "unlocked" after a job completes processing or fails all of its retry attempts. However, there may be situations where you would like your job to unlock immediately before it is processed. To accomplish this, your job should implement the ShouldBeUniqueUntilProcessing
contract instead of the ShouldBeUnique
contract:
<?php
use App\Models\Product;
use Illuminate\Contracts\Queue\ShouldQueue;
use Illuminate\Contracts\Queue\ShouldBeUniqueUntilProcessing;
class UpdateSearchIndex implements ShouldQueue, ShouldBeUniqueUntilProcessing
{
// ...
}
Unique Job Locks
Behind the scenes, when a ShouldBeUnique
job is dispatched, Laravel attempts to acquire a lock with the uniqueId
key. If the lock is not acquired, the job is not dispatched. This lock is released when the job completes processing or fails all of its retry attempts. By default, Laravel will use the default cache driver to obtain this lock. However, if you wish to use another driver for acquiring the lock, you may define a uniqueVia
method that returns the cache driver that should be used:
use Illuminate\Support\Facades\Cache;
class UpdateSearchIndex implements ShouldQueue, ShouldBeUnique
{
...
/**
* Get the cache driver for the unique job lock.
*
* @return \Illuminate\Contracts\Cache\Repository
*/
public function uniqueVia()
{
return Cache::driver('redis');
}
}
If you only need to limit the concurrent processing of a job, use the WithoutOverlapping
job middleware instead.
Job Middleware
Job middleware allow you to wrap custom logic around the execution of queued jobs, reducing boilerplate in the jobs themselves. For example, consider the following handle
method which leverages Laravel's Redis rate limiting features to allow only one job to process every five seconds:
use Illuminate\Support\Facades\Redis;
/**
* Execute the job.
*
* @return void
*/
public function handle()
{
Redis::throttle('key')->block(0)->allow(1)->every(5)->then(function () {
info('Lock obtained...');
// Handle job...
}, function () {
// Could not obtain lock...
return $this->release(5);
});
}
While this code is valid, the implementation of the handle
method becomes noisy since it is cluttered with Redis rate limiting logic. In addition, this rate limiting logic must be duplicated for any other jobs that we want to rate limit.
Instead of rate limiting in the handle method, we could define a job middleware that handles rate limiting. Laravel does not have a default location for job middleware, so you are welcome to place job middleware anywhere in your application. In this example, we will place the middleware in an app/Jobs/Middleware
directory:
<?php
namespace App\Jobs\Middleware;
use Illuminate\Support\Facades\Redis;
class RateLimited
{
/**
* Process the queued job.
*
* @param mixed $job
* @param callable $next
* @return mixed
*/
public function handle($job, $next)
{
Redis::throttle('key')
->block(0)->allow(1)->every(5)
->then(function () use ($job, $next) {
// Lock obtained...
$next($job);
}, function () use ($job) {
// Could not obtain lock...
$job->release(5);
});
}
}
As you can see, like route middleware, job middleware receive the job being processed and a callback that should be invoked to continue processing the job.
After creating job middleware, they may be attached to a job by returning them from the job's middleware
method. This method does not exist on jobs scaffolded by the make:job
Artisan command, so you will need to manually add it to your job class:
use App\Jobs\Middleware\RateLimited;
/**
* Get the middleware the job should pass through.
*
* @return array
*/
public function middleware()
{
return [new RateLimited];
}
Job middleware can also be assigned to queueable event listeners, mailables, and notifications.
Rate Limiting
Although we just demonstrated how to write your own rate limiting job middleware, Laravel actually includes a rate limiting middleware that you may utilize to rate limit jobs. Like route rate limiters, job rate limiters are defined using the RateLimiter
facade's for
method.
For example, you may wish to allow users to backup their data once per hour while imposing no such limit on premium customers. To accomplish this, you may define a RateLimiter
in the boot
method of your AppServiceProvider
:
use Illuminate\Cache\RateLimiting\Limit;
use Illuminate\Support\Facades\RateLimiter;
/**
* Bootstrap any application services.
*
* @return void
*/
public function boot()
{
RateLimiter::for('backups', function ($job) {
return $job->user->vipCustomer()
? Limit::none()
: Limit::perHour(1)->by($job->user->id);
});
}
In the example above, we defined an hourly rate limit; however, you may easily define a rate limit based on minutes using the perMinute
method. In addition, you may pass any value you wish to the by
method of the rate limit; however, this value is most often used to segment rate limits by customer:
return Limit::perMinute(50)->by($job->user->id);
Once you have defined your rate limit, you may attach the rate limiter to your backup job using the Illuminate\Queue\Middleware\RateLimited
middleware. Each time the job exceeds the rate limit, this middleware will release the job back to the queue with an appropriate delay based on the rate limit duration.
use Illuminate\Queue\Middleware\RateLimited;
/**
* Get the middleware the job should pass through.
*
* @return array
*/
public function middleware()
{
return [new RateLimited('backups')];
}
Releasing a rate limited job back onto the queue will still increment the job's total number of attempts
. You may wish to tune your tries
and maxExceptions
properties on your job class accordingly. Or, you may wish to use the retryUntil
method to define the amount of time until the job should no longer be attempted.
If you do not want a job to be retried when it is rate limited, you may use the dontRelease
method:
/**
* Get the middleware the job should pass through.
*
* @return array
*/
public function middleware()
{
return [(new RateLimited('backups'))->dontRelease()];
}
If you are using Redis, you may use the Illuminate\Queue\Middleware\RateLimitedWithRedis
middleware, which is fine-tuned for Redis and more efficient than the basic rate limiting middleware.
Preventing Job Overlaps
Laravel includes an Illuminate\Queue\Middleware\WithoutOverlapping
middleware that allows you to prevent job overlaps based on an arbitrary key. This can be helpful when a queued job is modifying a resource that should only be modified by one job at a time.
For example, let's imagine you have a queued job that updates a user's credit score and you want to prevent credit score update job overlaps for the same user ID. To accomplish this, you can return the WithoutOverlapping
middleware from your job's middleware
method:
use Illuminate\Queue\Middleware\WithoutOverlapping;
/**
* Get the middleware the job should pass through.
*
* @return array
*/
public function middleware()
{
return [new WithoutOverlapping($this->user->id)];
}
Any overlapping jobs will be released back to the queue. You may also specify the number of seconds that must elapse before the released job will be attempted again:
/**
* Get the middleware the job should pass through.
*
* @return array
*/
public function middleware()
{
return [(new WithoutOverlapping($this->order->id))->releaseAfter(60)];
}
If you wish to immediately delete any overlapping jobs so that they will not be retried, you may use the dontRelease
method:
/**
* Get the middleware the job should pass through.
*
* @return array
*/
public function middleware()
{
return [(new WithoutOverlapping($this->order->id))->dontRelease()];
}
The WithoutOverlapping
middleware is powered by Laravel's atomic lock feature. Sometimes, your job may unexpectedly fail or timeout in such a way that the lock is not released. Therefore, you may explicitly define a lock expiration time using the expireAfter
method. For example, the example below will instruct Laravel to release the WithoutOverlapping
lock three minutes after the job has started processing:
/**
* Get the middleware the job should pass through.
*
* @return array
*/
public function middleware()
{
return [(new WithoutOverlapping($this->order->id))->expireAfter(180)];
}
The WithoutOverlapping
middleware requires a cache driver that supports locks. Currently, the memcached
, redis
, dynamodb
, database
, file
, and array
cache drivers support atomic locks.
Throttling Exceptions
Laravel includes a Illuminate\Queue\Middleware\ThrottlesExceptions
middleware that allows you to throttle exceptions. Once the job throws a given number of exceptions, all further attempts to execute the job are delayed until a specified time interval lapses. This middleware is particularly useful for jobs that interact with third-party services that are unstable.
For example, let's imagine a queued job that interacts with a third-party API that begins throwing exceptions. To throttle exceptions, you can return the ThrottlesExceptions
middleware from your job's middleware
method. Typically, this middleware should be paired with a job that implements time based attempts:
use Illuminate\Queue\Middleware\ThrottlesExceptions;
/**
* Get the middleware the job should pass through.
*
* @return array
*/
public function middleware()
{
return [new ThrottlesExceptions(10, 5)];
}
/**
* Determine the time at which the job should timeout.
*
* @return \DateTime
*/
public function retryUntil()
{
return now()->addMinutes(5);
}
The first constructor argument accepted by the middleware is the number of exceptions the job can throw before being throttled, while the second constructor argument is the number of minutes that should elapse before the job is attempted again once it has been throttled. In the code example above, if the job throws 10 exceptions within 5 minutes, we will wait 5 minutes before attempting the job again.
When a job throws an exception but the exception threshold has not yet been reached, the job will typically be retried immediately. However, you may specify the number of minutes such a job should be delayed by calling the backoff
method when attaching the middleware to the job:
use Illuminate\Queue\Middleware\ThrottlesExceptions;
/**
* Get the middleware the job should pass through.
*
* @return array
*/
public function middleware()
{
return [(new ThrottlesExceptions(10, 5))->backoff(5)];
}
Internally, this middleware uses Laravel's cache system to implement rate limiting, and the job's class name is utilized as the cache "key". You may override this key by calling the by
method when attaching the middleware to your job. This may be useful if you have multiple jobs interacting with the same third-party service and you would like them to share a common throttling "bucket":
use Illuminate\Queue\Middleware\ThrottlesExceptions;
/**
* Get the middleware the job should pass through.
*
* @return array
*/
public function middleware()
{
return [(new ThrottlesExceptions(10, 10))->by('key')];
}
If you are using Redis, you may use the Illuminate\Queue\Middleware\ThrottlesExceptionsWithRedis
middleware, which is fine-tuned for Redis and more efficient than the basic exception throttling middleware.
Dispatching Jobs
Once you have written your job class, you may dispatch it using the dispatch
method on the job itself. The arguments passed to the dispatch
method will be given to the job's constructor:
<?php
namespace App\Http\Controllers;
use App\Http\Controllers\Controller;
use App\Jobs\ProcessPodcast;
use App\Models\Podcast;
use Illuminate\Http\Request;
class PodcastController extends Controller
{
/**
* Store a new podcast.
*
* @param \Illuminate\Http\Request $request
* @return \Illuminate\Http\Response
*/
public function store(Request $request)
{
$podcast = Podcast::create(...);
// ...
ProcessPodcast::dispatch($podcast);
}
}
If you would like to conditionally dispatch a job, you may use the dispatchIf
and dispatchUnless
methods:
ProcessPodcast::dispatchIf($accountActive, $podcast);
ProcessPodcast::dispatchUnless($accountSuspended, $podcast);
Delayed Dispatching
If you would like to specify that a job should not be immediately available for processing by a queue worker, you may use the delay
method when dispatching the job. For example, let's specify that a job should not be available for processing until 10 minutes after it has been dispatched:
<?php
namespace App\Http\Controllers;
use App\Http\Controllers\Controller;
use App\Jobs\ProcessPodcast;
use App\Models\Podcast;
use Illuminate\Http\Request;
class PodcastController extends Controller
{
/**
* Store a new podcast.
*
* @param \Illuminate\Http\Request $request
* @return \Illuminate\Http\Response
*/
public function store(Request $request)
{
$podcast = Podcast::create(...);
// ...
ProcessPodcast::dispatch($podcast)
->delay(now()->addMinutes(10));
}
}
The Amazon SQS queue service has a maximum delay time of 15 minutes.
Dispatching After The Response Is Sent To Browser
Alternatively, the dispatchAfterResponse
method delays dispatching a job until after the HTTP response is sent to the user's browser. This will still allow the user to begin using the application even though a queued job is still executing. This should typically only be used for jobs that take about a second, such as sending an email. Since they are processed within the current HTTP request, jobs dispatched in this fashion do not require a queue worker to be running in order for them to be processed:
use App\Jobs\SendNotification;
SendNotification::dispatchAfterResponse();
You may also dispatch
a closure and chain the afterResponse
method onto the dispatch
helper to execute a closure after the HTTP response has been sent to the browser:
use App\Mail\WelcomeMessage;
use Illuminate\Support\Facades\Mail;
dispatch(function () {
Mail::to('taylor@example.com')->send(new WelcomeMessage);
})->afterResponse();
Synchronous Dispatching
If you would like to dispatch a job immediately (synchronously), you may use the dispatchSync
method. When using this method, the job will not be queued and will be executed immediately within the current process:
<?php
namespace App\Http\Controllers;
use App\Http\Controllers\Controller;
use App\Jobs\ProcessPodcast;
use App\Models\Podcast;
use Illuminate\Http\Request;
class PodcastController extends Controller
{
/**
* Store a new podcast.
*
* @param \Illuminate\Http\Request $request
* @return \Illuminate\Http\Response
*/
public function store(Request $request)
{
$podcast = Podcast::create(...);
// Create podcast...
ProcessPodcast::dispatchSync($podcast);
}
}
Jobs & Database Transactions
While it is perfectly fine to dispatch jobs within database transactions, you should take special care to ensure that your job will actually be able to execute successfully. When dispatching a job within a transaction, it is possible that the job will be processed by a worker before the transaction has committed. When this happens, any updates you have made to models or database records during the database transaction may not yet be reflected in the database. In addition, any models or database records created within the transaction may not exist in the database.
Thankfully, Laravel provides several methods of working around this problem. First, you may set the after_commit
connection option in your queue connection's configuration array:
'redis' => [
'driver' => 'redis',
// ...
'after_commit' => true,
],
When the after_commit
option is true
, you may dispatch jobs within database transactions; however, Laravel will wait until all open database transactions have been committed before actually dispatching the job. Of course, if no database transactions are currently open, the job will be dispatched immediately.
If a transaction is rolled back due to an exception that occurs during the transaction, the dispatched jobs that were dispatched during that transaction will be discarded.
Setting the after_commit
configuration option to true
will also cause any queued event listeners, mailables, notifications, and broadcast events to be dispatched after all open database transactions have been committed.
Specifying Commit Dispatch Behavior Inline
If you do not set the after_commit
queue connection configuration option to true
, you may still indicate that a specific job should be dispatched after all open database transactions have been committed. To accomplish this, you may chain the afterCommit
method onto your dispatch operation:
use App\Jobs\ProcessPodcast;
ProcessPodcast::dispatch($podcast)->afterCommit();
Likewise, if the after_commit
configuration option is set to true
, you may indicate that a specific job should be dispatched immediately without waiting for any open database transactions to commit:
ProcessPodcast::dispatch($podcast)->beforeCommit();
Job Chaining
Job chaining allows you to specify a list of queued jobs that should be run in sequence after the primary job has executed successfully. If one job in the sequence fails, the rest of the jobs will not be run. To execute a queued job chain, you may use the chain
method provided by the Bus
facade. Laravel's command bus is a lower level component that queued job dispatching is built on top of:
use App\Jobs\OptimizePodcast;
use App\Jobs\ProcessPodcast;
use App\Jobs\ReleasePodcast;
use Illuminate\Support\Facades\Bus;
Bus::chain([
new ProcessPodcast,
new OptimizePodcast,
new ReleasePodcast,
])->dispatch();
In addition to chaining job class instances, you may also chain closures:
Bus::chain([
new ProcessPodcast,
new OptimizePodcast,
function () {
Podcast::update(...);
},
])->dispatch();
Deleting jobs using the $this->delete()
method within the job will not prevent chained jobs from being processed. The chain will only stop executing if a job in the chain fails.
Chain Connection & Queue
If you would like to specify the connection and queue that should be used for the chained jobs, you may use the onConnection
and onQueue
methods. These methods specify the queue connection and queue name that should be used unless the queued job is explicitly assigned a different connection / queue:
Bus::chain([
new ProcessPodcast,
new OptimizePodcast,
new ReleasePodcast,
])->onConnection('redis')->onQueue('podcasts')->dispatch();
Chain Failures
When chaining jobs, you may use the catch
method to specify a closure that should be invoked if a job within the chain fails. The given callback will receive the Throwable
instance that caused the job failure:
use Illuminate\Support\Facades\Bus;
use Throwable;
Bus::chain([
new ProcessPodcast,
new OptimizePodcast,
new ReleasePodcast,
])->catch(function (Throwable $e) {
// A job within the chain has failed...
})->dispatch();
Customizing The Queue & Connection
Dispatching To A Particular Queue
By pushing jobs to different queues, you may "categorize" your queued jobs and even prioritize how many workers you assign to various queues. Keep in mind, this does not push jobs to different queue "connections" as defined by your queue configuration file, but only to specific queues within a single connection. To specify the queue, use the onQueue
method when dispatching the job:
<?php
namespace App\Http\Controllers;
use App\Http\Controllers\Controller;
use App\Jobs\ProcessPodcast;
use App\Models\Podcast;
use Illuminate\Http\Request;
class PodcastController extends Controller
{
/**
* Store a new podcast.
*
* @param \Illuminate\Http\Request $request
* @return \Illuminate\Http\Response
*/
public function store(Request $request)
{
$podcast = Podcast::create(...);
// Create podcast...
ProcessPodcast::dispatch($podcast)->onQueue('processing');
}
}
Alternatively, you may specify the job's queue by calling the onQueue
method within the job's constructor:
<?php
namespace App\Jobs;
use Illuminate\Bus\Queueable;
use Illuminate\Contracts\Queue\ShouldQueue;
use Illuminate\Foundation\Bus\Dispatchable;
use Illuminate\Queue\InteractsWithQueue;
use Illuminate\Queue\SerializesModels;
class ProcessPodcast implements ShouldQueue
{
use Dispatchable, InteractsWithQueue, Queueable, SerializesModels;
/**
* Create a new job instance.
*
* @return void
*/
public function __construct()
{
$this->onQueue('processing');
}
}
Dispatching To A Particular Connection
If your application interacts with multiple queue connections, you may specify which connection to push a job to using the onConnection
method:
<?php
namespace App\Http\Controllers;
use App\Http\Controllers\Controller;
use App\Jobs\ProcessPodcast;
use App\Models\Podcast;
use Illuminate\Http\Request;
class PodcastController extends Controller
{
/**
* Store a new podcast.
*
* @param \Illuminate\Http\Request $request
* @return \Illuminate\Http\Response
*/
public function store(Request $request)
{
$podcast = Podcast::create(...);
// Create podcast...
ProcessPodcast::dispatch($podcast)->onConnection('sqs');
}
}
You may chain the onConnection
and onQueue
methods together to specify the connection and the queue for a job:
ProcessPodcast::dispatch($podcast)
->onConnection('sqs')
->onQueue('processing');
Alternatively, you may specify the job's connection by calling the onConnection
method within the job's constructor:
<?php
namespace App\Jobs;
use Illuminate\Bus\Queueable;
use Illuminate\Contracts\Queue\ShouldQueue;
use Illuminate\Foundation\Bus\Dispatchable;
use Illuminate\Queue\InteractsWithQueue;
use Illuminate\Queue\SerializesModels;
class ProcessPodcast implements ShouldQueue
{
use Dispatchable, InteractsWithQueue, Queueable, SerializesModels;
/**
* Create a new job instance.
*
* @return void
*/
public function __construct()
{
$this->onConnection('sqs');
}
}
Specifying Max Job Attempts / Timeout Values
Max Attempts
If one of your queued jobs is encountering an error, you likely do not want it to keep retrying indefinitely. Therefore, Laravel provides various ways to specify how many times or for how long a job may be attempted.
One approach to specifying the maximum number of times a job may be attempted is via the --tries
switch on the Artisan command line. This will apply to all jobs processed by the worker unless the job being processed specifies a more specific number of times it may be attempted:
php artisan queue:work --tries=3
If a job exceeds its maximum number of attempts, it will be considered a "failed" job. For more information on handling failed jobs, consult the failed job documentation.
You may take a more granular approach by defining the maximum number of times a job may be attempted on the job class itself. If the maximum number of attempts is specified on the job, it will take precedence over the --tries
value provided on the command line:
<?php
namespace App\Jobs;
class ProcessPodcast implements ShouldQueue
{
/**
* The number of times the job may be attempted.
*
* @var int
*/
public $tries = 5;
}
Time Based Attempts
As an alternative to defining how many times a job may be attempted before it fails, you may define a time at which the job should no longer be attempted. This allows a job to be attempted any number of times within a given time frame. To define the time at which a job should no longer be attempted, add a retryUntil
method to your job class. This method should return a DateTime
instance:
/**
* Determine the time at which the job should timeout.
*
* @return \DateTime
*/
public function retryUntil()
{
return now()->addMinutes(10);
}
You may also define a tries
property or retryUntil
method on your queued event listeners.
Max Exceptions
Sometimes you may wish to specify that a job may be attempted many times, but should fail if the retries are triggered by a given number of unhandled exceptions (as opposed to being released by the release
method directly). To accomplish this, you may define a maxExceptions
property on your job class:
<?php
namespace App\Jobs;
use Illuminate\Support\Facades\Redis;
class ProcessPodcast implements ShouldQueue
{
/**
* The number of times the job may be attempted.
*
* @var int
*/
public $tries = 25;
/**
* The maximum number of unhandled exceptions to allow before failing.
*
* @var int
*/
public $maxExceptions = 3;
/**
* Execute the job.
*
* @return void
*/
public function handle()
{
Redis::throttle('key')->allow(10)->every(60)->then(function () {
// Lock obtained, process the podcast...
}, function () {
// Unable to obtain lock...
return $this->release(10);
});
}
}
In this example, the job is released for ten seconds if the application is unable to obtain a Redis lock and will continue to be retried up to 25 times. However, the job will fail if three unhandled exceptions are thrown by the job.
Timeout
The pcntl
PHP extension must be installed in order to specify job timeouts.
Often, you know roughly how long you expect your queued jobs to take. For this reason, Laravel allows you to specify a "timeout" value. If a job is processing for longer than the number of seconds specified by the timeout value, the worker processing the job will exit with an error. Typically, the worker will be restarted automatically by a process manager configured on your server.
The maximum number of seconds that jobs can run may be specified using the --timeout
switch on the Artisan command line:
php artisan queue:work --timeout=30
If the job exceeds its maximum attempts by continually timing out, it will be marked as failed.
You may also define the maximum number of seconds a job should be allowed to run on the job class itself. If the timeout is specified on the job, it will take precedence over any timeout specified on the command line:
<?php
namespace App\Jobs;
class ProcessPodcast implements ShouldQueue
{
/**
* The number of seconds the job can run before timing out.
*
* @var int
*/
public $timeout = 120;
}
Sometimes, IO blocking processes such as sockets or outgoing HTTP connections may not respect your specified timeout. Therefore, when using these features, you should always attempt to specify a timeout using their APIs as well. For example, when using Guzzle, you should always specify a connection and request timeout value.
Failing On Timeout
If you would like to indicate that a job should be marked as failed on timeout, you may define the $failOnTimeout
property on the job class:
/**
* Indicate if the job should be marked as failed on timeout.
*
* @var bool
*/
public $failOnTimeout = true;
Error Handling
If an exception is thrown while the job is being processed, the job will automatically be released back onto the queue so it may be attempted again. The job will continue to be released until it has been attempted the maximum number of times allowed by your application. The maximum number of attempts is defined by the --tries
switch used on the queue:work
Artisan command. Alternatively, the maximum number of attempts may be defined on the job class itself. More information on running the queue worker can be found below.
Manually Releasing A Job
Sometimes you may wish to manually release a job back onto the queue so that it can be attempted again at a later time. You may accomplish this by calling the release
method:
/**
* Execute the job.
*
* @return void
*/
public function handle()
{
// ...
$this->release();
}
By default, the release
method will release the job back onto the queue for immediate processing. However, by passing an integer to the release
method you may instruct the queue to not make the job available for processing until a given number of seconds has elapsed:
$this->release(10);
Manually Failing A Job
Occasionally you may need to manually mark a job as "failed". To do so, you may call the fail
method:
/**
* Execute the job.
*
* @return void
*/
public function handle()
{
// ...
$this->fail();
}
If you would like to mark your job as failed because of an exception that you have caught, you may pass the exception to the fail
method:
$this->fail($exception);
For more information on failed jobs, check out the documentation on dealing with job failures.
Job Batching
Laravel's job batching feature allows you to easily execute a batch of jobs and then perform some action when the batch of jobs has completed executing. Before getting started, you should create a database migration to build a table to contain meta information about your job batches, such as their completion percentage. This migration may be generated using the queue:batches-table
Artisan command:
php artisan queue:batches-table
php artisan migrate
Defining Batchable Jobs
To define a batchable job, you should create a queueable job as normal; however, you should add the Illuminate\Bus\Batchable
trait to the job class. This trait provides access to a batch
method which may be used to retrieve the current batch that the job is executing within:
<?php
namespace App\Jobs;
use Illuminate\Bus\Batchable;
use Illuminate\Bus\Queueable;
use Illuminate\Contracts\Queue\ShouldQueue;
use Illuminate\Foundation\Bus\Dispatchable;
use Illuminate\Queue\InteractsWithQueue;
use Illuminate\Queue\SerializesModels;
class ImportCsv implements ShouldQueue
{
use Batchable, Dispatchable, InteractsWithQueue, Queueable, SerializesModels;
/**
* Execute the job.
*
* @return void
*/
public function handle()
{
if ($this->batch()->cancelled()) {
// Determine if the batch has been cancelled...
return;
}
// Import a portion of the CSV file...
}
}
Dispatching Batches
To dispatch a batch of jobs, you should use the batch
method of the Bus
facade. Of course, batching is primarily useful when combined with completion callbacks. So, you may use the then
, catch
, and finally
methods to define completion callbacks for the batch. Each of these callbacks will receive an Illuminate\Bus\Batch
instance when they are invoked. In this example, we will imagine we are queueing a batch of jobs that each process a given number of rows from a CSV file:
use App\Jobs\ImportCsv;
use Illuminate\Bus\Batch;
use Illuminate\Support\Facades\Bus;
use Throwable;
$batch = Bus::batch([
new ImportCsv(1, 100),
new ImportCsv(101, 200),
new ImportCsv(201, 300),
new ImportCsv(301, 400),
new ImportCsv(401, 500),
])->then(function (Batch $batch) {
// All jobs completed successfully...
})->catch(function (Batch $batch, Throwable $e) {
// First batch job failure detected...
})->finally(function (Batch $batch) {
// The batch has finished executing...
})->dispatch();
return $batch->id;
The batch's ID, which may be accessed via the $batch->id
property, may be used to query the Laravel command bus for information about the batch after it has been dispatched.
Since batch callbacks are serialized and executed at a later time by the Laravel queue, you should not use the $this
variable within the callbacks.
Naming Batches
Some tools such as Laravel Horizon and Laravel Telescope may provide more user-friendly debug information for batches if batches are named. To assign an arbitrary name to a batch, you may call the name
method while defining the batch:
$batch = Bus::batch([
// ...
])->then(function (Batch $batch) {
// All jobs completed successfully...
})->name('Import CSV')->dispatch();
Batch Connection & Queue
If you would like to specify the connection and queue that should be used for the batched jobs, you may use the onConnection
and onQueue
methods. All batched jobs must execute within the same connection and queue:
$batch = Bus::batch([
// ...
])->then(function (Batch $batch) {
// All jobs completed successfully...
})->onConnection('redis')->onQueue('imports')->dispatch();
Chains Within Batches
You may define a set of chained jobs within a batch by placing the chained jobs within an array. For example, we may execute two job chains in parallel and execute a callback when both job chains have finished processing:
use App\Jobs\ReleasePodcast;
use App\Jobs\SendPodcastReleaseNotification;
use Illuminate\Bus\Batch;
use Illuminate\Support\Facades\Bus;
Bus::batch([
[
new ReleasePodcast(1),
new SendPodcastReleaseNotification(1),
],
[
new ReleasePodcast(2),
new SendPodcastReleaseNotification(2),
],
])->then(function (Batch $batch) {
// ...
})->dispatch();
Adding Jobs To Batches
Sometimes it may be useful to add additional jobs to a batch from within a batched job. This pattern can be useful when you need to batch thousands of jobs which may take too long to dispatch during a web request. So, instead, you may wish to dispatch an initial batch of "loader" jobs that hydrate the batch with even more jobs:
$batch = Bus::batch([
new LoadImportBatch,
new LoadImportBatch,
new LoadImportBatch,
])->then(function (Batch $batch) {
// All jobs completed successfully...
})->name('Import Contacts')->dispatch();
In this example, we will use the LoadImportBatch
job to hydrate the batch with additional jobs. To accomplish this, we may use the add
method on the batch instance that may be accessed via the job's batch
method:
use App\Jobs\ImportContacts;
use Illuminate\Support\Collection;
/**
* Execute the job.
*
* @return void
*/
public function handle()
{
if ($this->batch()->cancelled()) {
return;
}
$this->batch()->add(Collection::times(1000, function () {
return new ImportContacts;
}));
}
You may only add jobs to a batch from within a job that belongs to the same batch.
Inspecting Batches
The Illuminate\Bus\Batch
instance that is provided to batch completion callbacks has a variety of properties and methods to assist you in interacting with and inspecting a given batch of jobs:
// The UUID of the batch...
$batch->id;
// The name of the batch (if applicable)...
$batch->name;
// The number of jobs assigned to the batch...
$batch->totalJobs;
// The number of jobs that have not been processed by the queue...
$batch->pendingJobs;
// The number of jobs that have failed...
$batch->failedJobs;
// The number of jobs that have been processed thus far...
$batch->processedJobs();
// The completion percentage of the batch (0-100)...
$batch->progress();
// Indicates if the batch has finished executing...
$batch->finished();
// Cancel the execution of the batch...
$batch->cancel();
// Indicates if the batch has been cancelled...
$batch->cancelled();
Returning Batches From Routes
All Illuminate\Bus\Batch
instances are JSON serializable, meaning you can return them directly from one of your application's routes to retrieve a JSON payload containing information about the batch, including its completion progress. This makes it convenient to display information about the batch's completion progress in your application's UI.
To retrieve a batch by its ID, you may use the Bus
facade's findBatch
method:
use Illuminate\Support\Facades\Bus;
use Illuminate\Support\Facades\Route;
Route::get('/batch/{batchId}', function (string $batchId) {
return Bus::findBatch($batchId);
});
Cancelling Batches
Sometimes you may need to cancel a given batch's execution. This can be accomplished by calling the cancel
method on the Illuminate\Bus\Batch
instance:
/**
* Execute the job.
*
* @return void
*/
public function handle()
{
if ($this->user->exceedsImportLimit()) {
return $this->batch()->cancel();
}
if ($this->batch()->cancelled()) {
return;
}
}
As you may have noticed in previous examples, batched jobs should typically check to see if the batch has been cancelled at the beginning of their handle
method:
/**
* Execute the job.
*
* @return void
*/
public function handle()
{
if ($this->batch()->cancelled()) {
return;
}
// Continue processing...
}
Batch Failures
When a batched job fails, the catch
callback (if assigned) will be invoked. This callback is only invoked for the first job that fails within the batch.
Allowing Failures
When a job within a batch fails, Laravel will automatically mark the batch as "cancelled". If you wish, you may disable this behavior so that a job failure does not automatically mark the batch as cancelled. This may be accomplished by calling the allowFailures
method while dispatching the batch:
$batch = Bus::batch([
// ...
])->then(function (Batch $batch) {
// All jobs completed successfully...
})->allowFailures()->dispatch();
Retrying Failed Batch Jobs
For convenience, Laravel provides a queue:retry-batch
Artisan command that allows you to easily retry all of the failed jobs for a given batch. The queue:retry-batch
command accepts the UUID of the batch whose failed jobs should be retried:
php artisan queue:retry-batch 32dbc76c-4f82-4749-b610-a639fe0099b5
Pruning Batches
Without pruning, the job_batches
table can accumulate records very quickly. To mitigate this, you should schedule the queue:prune-batches
Artisan command to run daily:
$schedule->command('queue:prune-batches')->daily();
By default, all finished batches that are more than 24 hours old will be pruned. You may use the hours
option when calling the command to determine how long to retain batch data. For example, the following command will delete all batches that finished over 48 hours ago:
$schedule->command('queue:prune-batches --hours=48')->daily();
Sometimes, your jobs_batches
table may accumulate batch records for batches that never completed successfully, such as batches where a job failed and that job was never retried successfully. You may instruct the queue:prune-batches
command to prune these unfinished batch records using the unfinished
option:
$schedule->command('queue:prune-batches --hours=48 --unfinished=72')->daily();
Queueing Closures
Instead of dispatching a job class to the queue, you may also dispatch a closure. This is great for quick, simple tasks that need to be executed outside of the current request cycle. When dispatching closures to the queue, the closure's code content is cryptographically signed so that it can not be modified in transit:
$podcast = App\Podcast::find(1);
dispatch(function () use ($podcast) {
$podcast->publish();
});