Genre: eLearning | MP4 | Video: AVC, 1280x720 | Audio: aac, 48 kHz
Language: English | Size: 208 MB | Duration: 11 episodes (1h16m) | Intermediate
Learning about queues can be a daunting task. It's not fun to be met with confusing jargon that you can't decipher. But that's what I'm here for. Let's incrementally break it all down into small steps that anyone can understand. In no time, you'll be throwing delayed jobs onto the queue like a pro.
Section 1 The Essentials
Pizza Time
Before we write a single line of code, give me two minutes to provide a real-life illustration of queues and workers. We'll use the example of a pizza delivery restaurant.
Dispatch Your First Job
Now that you have a basic idea of what a queue is, let's dispatch our first job using Laravel. We'll also learn about delayed job execution, and when you might reach for it.
Job Classes and Daemons
Now that you understand how to dispatch a simple closure, let's next create a dedicated Job class, while discussing serialization and daemons.
Dispatchable
We've learned how to use the global dispatch() function, but there's an alternative option you should consider as well. By default, each Job class includes a Dispatchable trait.
Failed Jobs
So far, we've reviewed the "happy path" for a job, but what if an error or exception is thrown along the way? If you don't specify a maximum number of tries for your queue worker, the job will retry over and over again. In this episode, we'll learn how to fix this by creating a "failed_jobs" table.
A UI For Your Redis-Backed Queues
When working with queues, it can often prove difficult to see what's happening. For example, how many jobs ran in the last hour? Did any of them fail? How many workers are running? And what about only the jobs that match a particular tag? Let's solve this by installing Laravel Horizon, a dashboard for your Redis-backed queues.
Multiple Queues and Workers
In this episode, we'll review how to create multiple queue stacks and workers, as well as when and why you might do so.
Storing Jobs in the Database
If you don't have much control over the environment your application runs in, you might consider using the database queue connection. With this approach, rather than using Redis or Memcached, your jobs will instead be stored and fetched from the database.
Take a Ride on the Laravel Pipeline
Before we dig in to learn how Laravel dispatches jobs to the queue, we must first learn about pipelines. It's possible that you've never come across Laravel's Pipeline API! It's a fluent interface for sending an object or piece of data through a series of "pipes," each of which has the opportunity to modify or verify it in some way.
Section 2 Source Diving
Source Diving the Dispatcher
Now that you understand how pipelines work, let's dive into the Laravel source code to figure out what precisely happens when we call ReconcileAccount::dispatch($user).
Source Diving the Queue Worker
Source diving isn't always the most enjoyable thing in the world, but, nonetheless, it's an excellent way to improve your understanding of an API. In this episode, we'll learn what happens when a queued job is dispatched, as well as how the worker executes the job in a separate request.
