How does the HTTP request work in Laravel?

Question

When i visit to my.site/api/genre/slug-name

In route/api.php:

Route::prefix('genre')->group(function () {
    Route::get('/{slug}', [FilmController::class,'getFilmByGenre'])->name('api_genre_film');
});

In getFilmByGenre:

public function getFilmByGenre(Request $request, string $slug)
{
    dd($slug, $request->slug, $request->get("slug")); // "slug-name" - "slug-name" - null
}

Can anyone please explain to me the difference when using $slug, $request->slug and $request->get("slug")?

I'm using laravel 10.x. Thanks for your help!

Answer 1

The reason for this is because of the difference in Route Parameter Binding vs. It is a query parameter. On the concepts of Route Parameter Binding vs. Search Query Parameter.

The $slug parameter gets its value directly from the route definition. It's a route parameter, bound to the URI pattern. $request->get("slug") tries to retrieve a value for the key "slug" from the query string. The query string is the part of the URL that comes after the ? symbol and consists of key-value pairs separated by &. In your case, there's no "slug" key in the query string (my.site/api/genre/slug-name), hence $request->get("slug") is null.

and for $reuset->slug Laravel internally maps route parameters to properties of the request object. So if you have a route parameter named {slug}, Laravel will automatically bind it to the $request->slug property.

In summary:

$slug: "slug-name" (value extracted from the route parameter)

$request->slug: "slug-name" (When you access $request->slug, you're accessing the same value as $slug)

$request->get("slug"): null (no "slug" key in the query string)