Laravel 中“Closure”类的源代码

Question

RedirectIfAuthenticated middleware of Laravel uses a class called Closure.

Code:

<?php

namespace App\Http\Middleware;

use Closure;
use Illuminate\Support\Facades\Auth;

class RedirectIfAuthenticated
{
    /**
     * Handle an incoming request.
     *
     * @param  \Illuminate\Http\Request  $request
     * @param  \Closure  $next
     * @param  string|null  $guard
     * @return mixed
     */
    public function handle($request, Closure $next, $guard = null)
    {
        if (Auth::guard($guard)->check()) {
            return redirect('/home');
        }

        return $next($request);
    }
}

Now, I need to find out the source code of that above mentioned Closure class. I'm passing hard times to understand how this next() method is functioning here.

Thanks.

Answer 1

In this particular case, you'll want to read up on Middleware . They are basically a list/stack where you have various things happening before you get to the route handler (usually a controller). The $next parameter is a callback that calls the next middleware in the stack.

To figure out what $next is, you'll need to figure out the middleware that comes after RedirectIfAuthenticated . The easiest way to tell that is to php artisan route:list and look at all the middleware for that route, then look at $middlewarePriority . If the middlewares are not found in the priority variable, then middleware if first in first out, in that if you specify multiple middlewares for a route, the first one defined happens first.

If you only have a single middleware on the route then you are getting to the route, unless you're using other things such asForm Requests .