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Question

In other frameworks, the concept of request forwarding exists, were a request can be internally redirected to another controller action within the app without responding back to the user with an explicit redirect.

For an ecommerce example, if a product has a SEO-friendly URL of /red-shoes.html, a request to that URL would internally forward to /catalog/product/id/1234. The user would receive a 200 response code and the product page for product ID 1234 would be rendered at the original URL of /red-shoes.html. The behavior I'm trying to avoid is issuing a 301 redirect to /catalog/product/view/id/1234 and losing the friendly URL.

How can this be accomplished in Laravel (5.7)? I can introduce a piece of middleware to intercept the request, but in middleware, I can only redirect within the app. redirect() sends a 302 back to the user, which I don't want.

namespace App\Http\Middleware;

use Closure;
use App\Rewrite;

class ProductForward
{
    public function handle($request, Closure $next)
    {
        // make a lookup to see if URI in request matches a known product
        $productId = Product::lookupRequest($request);
        if ($productId) {  // if matches, forward to product controller
            return redirect()->route('catalog_product', ['id' => $productId]);  // not desired
        }
        // if no match is found, continue on with the request
        return $next($request);
    }
}

As a follow-up, is it possible to execute this lookup after routing has completed, if no route matches?

For example, assume the route /login exists to render the login page. If the user goes to /login, there's no point in looking up a product-friendly URL for this request - just render the login page. But, if the user visits /blue-shoe.html, and that's not a pre-defined route in Laravel, execute the product lookup and forward after app routing but before a 404 is rendered.

Answer 1

Could SEO-friendly URLs be in a section like products/red-shoes?

Then you can create a route with parameter like Route::get('products/{seoName}'); that will lead to the same controller you use for handling requests like /catalog/product/view/id/1234. There you can resolve and find out that a controller's action was reached with product's ID or seo-name and show a matching product.

Basically, you can have two routes products/red-shoes and /catalog/product/view/id/1234 that will show the same page, without redirect.

Controller action

Also, you can execute a controller method directly from the middleware.

Instead of calling

return redirect()->route('catalog_product', ['id' => $productId]);

you may run something like

return app('App\Http\Controllers\ProductController')->show($productId);

Then you will get a content of a product page without a redirect.

Fallback route

To prevent running the middleware on every request you can use a fallback route.

Route::fallback(function () {
    //
});

Fallback route will be executed only if a request doesn't match any of registered routes. There you can search for a product and if nothing then return a 404 response.

So you will get something like this:

Route::fallback(function ()
{
    // make a lookup to see if URI in request matches a known product
    $productId = Product::lookupRequest(request());
    if ($productId) {  // if matches, forward to product controller
        return app('App\Http\Controllers\ProductController')->show($productId);
    }
    abort(404);
}

Fallback route should be registered last in your file.

More info https://laravel.com/docs/5.7/routing#fallback-routes