Include default global middleware for interacting with "Accept-Language" HTTP header

[SimonARG]

Rationale:

It's 2024. All projects are global, yet Laravel doesn't include any way to automatically detect client-side locale.

In my mind there's no reason to not use this as default behaviour, however I would understand shipping the middleware without registering it, or making it route-specific instead of global.

As for other methods for setting locale like URL parameters, for example: /api/{LOCALE}/v1/ being set to either use a function or middleware to set the locale depending on the {LOCALE} parameter. I just don't think that this, or any other alternative methods, are useful, when the HTTP spec gives us a standard method in the Accept-Language header.

And don't get me started on using <input type='hidden' name='locale' value='LOCALE'>...

app/Http/Middleware/SetLocale.php:

namespace App\Http\Middleware;

use Closure;
use Illuminate\Support\Facades\App;

class SetLocale
{
    /**
     * Handle an incoming request.
     *
     * @param  \Illuminate\Http\Request  $request
     * @param  \Closure  $next
     * @return mixed
     */
    public function handle($request, Closure $next)
    {
        if ($locale = $request->header('Accept-Language')) {
            App::setLocale($locale);
        }

        return $next($request);
    }
}

bootstrap/app.php:

->withMiddleware(function (Middleware $middleware) {
     $middleware->append(SetLocale::class);
})

[LucaRed]

It's not that simple, because the Accept-Language header may contain multiple weighted codes or even invalid codes (never trust client-side provided data). But I like the general idea of standardizing that as a default middleware.

[shaedrich]

One reason more to not let any developer temper with this by parsing it on their own but providing a standardized interface, that can help interpreting the weighing (see @mbabker's reply).

[mbabker]

Luckily, the Symfony request already has a getLanguages() method to read that header, and a getPreferredLanguage() method to find the preferred language. So you really only need to use the existing API that Laravel inherits to configure your application.

[marius-mcp]

Why should all be embedded in Laravel? External libs are not ok for this for example?

I see that all people want the framework to solve their problems. To have all they need. :)

[marius-mcp]

Amin for that.

[marius-mcp]

Ideally the docs should contain notes for things not included in the framework by default.
If you want locale, you can use these packages: ....
If you want relations that include more than 3 tables, you can use these packages:...
(If you want useless overhead, you can use these packages: ....) Joke.
etc.

[mbabker]

By this logic, you're saying the framework's translation component shouldn't be baked in but require a third-party package. Reading the Accept-Language header ties in very closely to handling translations in a number of cases, and is much less overhead compared to a number of the other framework features I routinely disable for some of the sites I deploy.

Granted, the tooling for this is already in the framework by way of the Symfony APIs that Laravel tries to steer you away from, but implementing it in middleware seems like it's a handful of lines of code at best.

[shaedrich]

Ideally the docs should contain notes for things not included in the framework by default. If you want locale, you can use these packages: .... If you want relations that include more than 3 tables, you can use these packages:... (If you want useless overhead, you can use these packages: ....) Joke. etc.

I would quite like this 👍🏻

[marius-mcp]

@mbabker I agree that many things are already in the framework that are less important than this. But a hand full of code multiplied by a certain amount can lead to big unused overhead for many projects. But laravel will never be like this. It will become bigger and bigger, slower and slower. Now with the help of octane and franken php, more and more load will be inserted into laravel (because it can handle it). The result will be exactly what we see in the computer hardware. New laptop that could fly under windows xp/ubuntu 14.04, but hangs in ubunu 24.04 or windows 11. Politics...