Illuminate\Contracts\Container\BindingResolutionException Target class [admin] does not exist. (Laravel Version 7.30.6)

Question

The error I face is

Illuminate\Contracts\Container\BindingResolutionException Target class [admin] does not exist. (Laravel Version 7.30.6)

My Routes are given below :

//admin routes
Route::group(['prefix' =>'admin', 'middleware' => ['auth', 'admin']], function() {

    Route::get('/', 'Backend\PagesController@index')->name('admin.index');
    Route::get('/login', 'Auth\Admin\LoginController@showLoginForm')->name('admin.login');
    Route::post('/login/submit', 'Auth\Admin\LoginController@login')->name('admin.login.submit');
    Route::post('/logout/submit', 'Auth\Admin\LoginController@logout')->name('admin.logout');
});

Kernel.php code

 protected $routeMiddleware = [
        'auth' => \App\Http\Middleware\Authenticate::class,
        'auth.basic' => \Illuminate\Auth\Middleware\AuthenticateWithBasicAuth::class,
        'bindings' => \Illuminate\Routing\Middleware\SubstituteBindings::class,
        'cache.headers' => \Illuminate\Http\Middleware\SetCacheHeaders::class,
        'can' => \Illuminate\Auth\Middleware\Authorize::class,
        'guest' => \App\Http\Middleware\RedirectIfAuthenticated::class,
        'password.confirm' => \Illuminate\Auth\Middleware\RequirePassword::class,
        'signed' => \Illuminate\Routing\Middleware\ValidateSignature::class,
        'throttle' => \Illuminate\Routing\Middleware\ThrottleRequests::class,
        'verified' => \Illuminate\Auth\Middleware\EnsureEmailIsVerified::class,
        

    ];

Answer 1

You used a middleware named admin in your route middleware, so you must create an alias in $routeMiddleware.

Add something like this to your $routeMiddleware array:

Kernel.php:

    protected $routeMiddleware = [
        'auth' => \App\Http\Middleware\Authenticate::class,
        'auth.basic' => \Illuminate\Auth\Middleware\AuthenticateWithBasicAuth::class,
        'bindings' => \Illuminate\Routing\Middleware\SubstituteBindings::class,
        'cache.headers' => \Illuminate\Http\Middleware\SetCacheHeaders::class,
        'can' => \Illuminate\Auth\Middleware\Authorize::class,
        'guest' => \App\Http\Middleware\RedirectIfAuthenticated::class,
        'password.confirm' => \Illuminate\Auth\Middleware\RequirePassword::class,
        'signed' => \Illuminate\Routing\Middleware\ValidateSignature::class,
        'throttle' => \Illuminate\Routing\Middleware\ThrottleRequests::class,
        'verified' => \Illuminate\Auth\Middleware\EnsureEmailIsVerified::class,
        // add below line
        'admin' => \App\Http\Middleware\Admin::class

    ];

Where the mentioned class is your admin middleware.

app/Http/Middleware/Admin.php (or any other class as long as it has a handle method ):

// 
<?php

namespace App\Http\Middleware;

use Closure;
use Illuminate\Http\Request;

class Admin
{
    public function handle(Request $request, Closure $next)
    {
        // check if user is an admin and process the request
        if (auth()->user()->is_admin) {
            return $next($request);
        }
        // user isn't an admin
        abort(403);
    }
}