Laravel Pipelines & Composable Job Middleware

Laravel features a Pipeline implementation that allows for the creation of a series of pipes through which a value should pass. A pipe is a callable or a class with a specific public method that takes two arguments: a "passable" and a Closure. The passable is the value being sent through the pipeline, and the Closure is a wrapper that calls the next pipe in the pipeline. Pipelines can be used for various purposes, including HTTP request middleware and Job middleware. In the case of HTTP middleware, Laravel uses Pipelines internally for the HTTP request lifecycle. For Job middleware, it can be used to track metrics, handle errors, and verify job expiration. Job middleware can also be used to ensure that jobs requiring an authenticated user are logged in during job execution. This can be achieved by creating a middleware class that logs in the user before passing the job to the next middleware in the pipeline. Laravel also provides a way to create composable middleware using traits. The HasMiddleware trait can be used to add a middleware method that dynamically creates an array of middleware based on the traits used by a job class. This allows for easy addition of middleware to jobs by creating traits that define the middleware. In Laravel 11.26 and later, the artisan make:job-middleware command can be used to generate Job middleware. Overall, the Laravel Pipeline is a versatile tool that can be used for any composable series of operations that act on a value.