[5.7] Add thenReturn method to Pipeline

[timacdonald]

Often when using a pipeline there is additional work to be done to the object passed through. A good example of this is using the Pipeline to apply additional filters to a query builder, perhaps based off a request's query parameters. Current you could do the following...

$users = app(Pipeline::class)
    ->send(User::query())
    ->through($pipes)
    ->then(function ($query) {
        return $query
            ->whereConfirmedEmail()
            ->whereAccountActive()
            ->get();
    });

or...

app(Pipeline::class)
    ->send($query = User::query())
    ->through($pipes)
    ->then(function () {});

$users = $query->whereConfirmedEmail()->whereAccountActive()->get();

or...

$query = User::whereConfirmedEmail()->whereAccountActive();

$users = app(Pipeline::class)
    ->send($query)
    ->through($pipes)
    ->then(function ($query) {
        return $query->get();
    });

or you could merge in a closure based pipe, and so on.

Adding a helper method to return the $passable allows for continued chaining in the same scope, so the above examples become...

$users = app(Pipeline::class)
    ->send(User::query())
    ->through($pipes)
    ->thenReturn()
    ->whereConfirmedEmail()
    ->whereAccountActive()
    ->get();

which I personally think feels nice when simple running the pipeline does not complete the preparation/manipulation of the $passable.

There are also scenarios where you just wanna run something through a pipeline and you don't need to do any additional work to it...

return app(Pipeline::class)
    ->send($thing)
    ->through($pipes)
    // ->then(function ($thing) {
    //     return $thing;
    // });
    ->thenReturn();

Although I have named the method thenReturn, it may not be the best name for this. I thought run might also be an option, as you are running the passable through the pipeline.

app(Pipeline::class)
    ->send($thing)
    ->through($pipes)
    ->run()
    ...

[torkiljohnsen]

@timacdonald Nice addition! I would be interested in seeing how you use pipeline to build a query. More of a full example if you can? Always found this part tedious and I am currently looking for alternatives to my "IndexQueryBuilder" solution, which I am not happy with.

[timacdonald]

Hey @torkiljohnsen I am using a variation of what @davidhemphill introduced me to during his LaraconAU talk last year. You should check it out because his way of handling it a lot simpler than mine, and it is a really nice pattern (plus it is just a really good talk): https://www.youtube.com/watch?v=dd-iHhmSi2k

I've altered my approach slightly so that instead of passing the request through the stack, I pass the query through. Hoping to get a chance to write it up in more detail, but here is what I end up with. Hopefully it makes sense with just this code dump haha...

Controller

class TeamController
{
    public function index(TeamRequest $request)
    {
        $teams = pipe(Team::query())
            ->through($request->queryFilters())
            ->thenReturn()
            ->orderBy('name')
            ->withCount('members')
            ->simplePaginate(50);

        // ...
    }
}

Request

class TeamRequest extends Request
{
    protected $queryFilters = [
        \App\Http\Filters\TeamIsFullFilter::class,
        \App\Http\Filters\TeamIsPublicFilter::class,
    ];
}

Query filter

class TeamIsPublicFilter
{
    private $request;

    public function __construct($request)
    {
        $this->request = $request;
    }

    public function handle($query, $next)
    {
        if ($this->request->filled('is_public')) {
            $query->wherePublic((bool) $this->request->query('is_public'));
        }

        return $next($query);
    }
}

---

Then everything below this point is just the infrastructure I setup to allow it all to come together...

Global pipe helper

function pipe($passable)
{
    return app(Pipeline::class)->send($passable);
}

Base request

abstract class Request extends FormRequest
{
    protected $queryFilters = [];

    public function queryFilters()
    {
        return collect($this->queryFilters)->map(function ($class) {
            return new $class($this);
        });
    }

    public function authorize()
    {
        return true;
    }

    public function rules()
    {
        return [];
    }
}

[timacdonald]

If ya have any questions after seeing all this, feel free to hit me up 👍

[timacdonald]

I should mention that if you want a package to throw at the problem you could check out https://github.com/spatie/laravel-query-builder

[torkiljohnsen]

Awesome stuff, will look into those things! Thanks a lot 👍