ErrorException: Trying to get property 'author' of non-object in file /home/forge/gitapress.org/app/Http/Controllers/ProductController.php on line 172 #0 /home/forge/gitapress.org/app/Http/Controllers/ProductController.php(172): Illuminate\Foundation\Bootstrap\HandleExceptions->handleError() #1 /home/forge/gitapress.org/vendor/laravel/framework/src/Illuminate/Routing/Controller.php(54): App\Http\Controllers\ProductController->book_detail() #2 /home/forge/gitapress.org/vendor/laravel/framework/src/Illuminate/Routing/ControllerDispatcher.php(45): Illuminate\Routing\Controller->callAction() #3 /home/forge/gitapress.org/vendor/laravel/framework/src/Illuminate/Routing/Route.php(219): Illuminate\Routing\ControllerDispatcher->dispatch() #4 /home/forge/gitapress.org/vendor/laravel/framework/src/Illuminate/Routing/Route.php(176): Illuminate\Routing\Route->runController() #5 /home/forge/gitapress.org/vendor/laravel/framework/src/Illuminate/Routing/Router.php(681): Illuminate\Routing\Route->run() #6 /home/forge/gitapress.org/vendor/laravel/framework/src/Illuminate/Pipeline/Pipeline.php(130): Illuminate\Routing\Router->Illuminate\Routing\{closure}() #7 /home/forge/gitapress.org/vendor/laravel/framework/src/Illuminate/Routing/Middleware/SubstituteBindings.php(41): Illuminate\Pipeline\Pipeline->Illuminate\Pipeline\{closure}() #8 /home/forge/gitapress.org/vendor/laravel/framework/src/Illuminate/Pipeline/Pipeline.php(171): Illuminate\Routing\Middleware\SubstituteBindings->handle() #9 /home/forge/gitapress.org/app/Http/Middleware/VerifyCsrfMiddleware.php(13): Illuminate\Pipeline\Pipeline->Illuminate\Pipeline\{closure}() #10 /home/forge/gitapress.org/vendor/laravel/framework/src/Illuminate/Pipeline/Pipeline.php(171): App\Http\Middleware\VerifyCsrfMiddleware->handle() #11 /home/forge/gitapress.org/vendor/laravel/framework/src/Illuminate/View/Middleware/ShareErrorsFromSession.php(49): Illuminate\Pipeline\Pipeline->Illuminate\Pipeline\{closure}() #12 /home/forge/gitapress.org/vendor/laravel/framework/src/Illuminate/Pipeline/Pipeline.php(171): Illuminate\View\Middleware\ShareErrorsFromSession->handle() #13 /home/forge/gitapress.org/vendor/laravel/framework/src/Illuminate/Session/Middleware/StartSession.php(56): Illuminate\Pipeline\Pipeline->Illuminate\Pipeline\{closure}() #14 /home/forge/gitapress.org/vendor/laravel/framework/src/Illuminate/Pipeline/Pipeline.php(171): Illuminate\Session\Middleware\StartSession->handle() #15 /home/forge/gitapress.org/vendor/laravel/framework/src/Illuminate/Cookie/Middleware/AddQueuedCookiesToResponse.php(37): Illuminate\Pipeline\Pipeline->Illuminate\Pipeline\{closure}() #16 /home/forge/gitapress.org/vendor/laravel/framework/src/Illuminate/Pipeline/Pipeline.php(171): Illuminate\Cookie\Middleware\AddQueuedCookiesToResponse->handle() #17 /home/forge/gitapress.org/vendor/laravel/framework/src/Illuminate/Cookie/Middleware/EncryptCookies.php(67): Illuminate\Pipeline\Pipeline->Illuminate\Pipeline\{closure}() #18 /home/forge/gitapress.org/vendor/laravel/framework/src/Illuminate/Pipeline/Pipeline.php(171): Illuminate\Cookie\Middleware\EncryptCookies->handle() #19 /home/forge/gitapress.org/vendor/laravel/framework/src/Illuminate/Pipeline/Pipeline.php(105): Illuminate\Pipeline\Pipeline->Illuminate\Pipeline\{closure}() #20 /home/forge/gitapress.org/vendor/laravel/framework/src/Illuminate/Routing/Router.php(683): Illuminate\Pipeline\Pipeline->then() #21 /home/forge/gitapress.org/vendor/laravel/framework/src/Illuminate/Routing/Router.php(658): Illuminate\Routing\Router->runRouteWithinStack() #22 /home/forge/gitapress.org/vendor/laravel/framework/src/Illuminate/Routing/Router.php(624): Illuminate\Routing\Router->runRoute() #23 /home/forge/gitapress.org/vendor/laravel/framework/src/Illuminate/Routing/Router.php(613): Illuminate\Routing\Router->dispatchToRoute() #24 /home/forge/gitapress.org/vendor/laravel/framework/src/Illuminate/Foundation/Http/Kernel.php(170): Illuminate\Routing\Router->dispatch() #25 /home/forge/gitapress.org/vendor/laravel/framework/src/Illuminate/Pipeline/Pipeline.php(130): Illuminate\Foundation\Http\Kernel->Illuminate\Foundation\Http\{closure}() #26 /home/forge/gitapress.org/vendor/laravel/framework/src/Illuminate/Foundation/Http/Middleware/TransformsRequest.php(21): Illuminate\Pipeline\Pipeline->Illuminate\Pipeline\{closure}() #27 /home/forge/gitapress.org/vendor/laravel/framework/src/Illuminate/Pipeline/Pipeline.php(171): Illuminate\Foundation\Http\Middleware\TransformsRequest->handle() #28 /home/forge/gitapress.org/vendor/laravel/framework/src/Illuminate/Foundation/Http/Middleware/TransformsRequest.php(21): Illuminate\Pipeline\Pipeline->Illuminate\Pipeline\{closure}() #29 /home/forge/gitapress.org/vendor/laravel/framework/src/Illuminate/Pipeline/Pipeline.php(171): Illuminate\Foundation\Http\Middleware\TransformsRequest->handle() #30 /home/forge/gitapress.org/vendor/laravel/framework/src/Illuminate/Foundation/Http/Middleware/ValidatePostSize.php(27): Illuminate\Pipeline\Pipeline->Illuminate\Pipeline\{closure}() #31 /home/forge/gitapress.org/vendor/laravel/framework/src/Illuminate/Pipeline/Pipeline.php(171): Illuminate\Foundation\Http\Middleware\ValidatePostSize->handle() #32 /home/forge/gitapress.org/vendor/laravel/framework/src/Illuminate/Foundation/Http/Middleware/CheckForMaintenanceMode.php(63): Illuminate\Pipeline\Pipeline->Illuminate\Pipeline\{closure}() #33 /home/forge/gitapress.org/vendor/laravel/framework/src/Illuminate/Pipeline/Pipeline.php(171): Illuminate\Foundation\Http\Middleware\CheckForMaintenanceMode->handle() #34 /home/forge/gitapress.org/vendor/fideloper/proxy/src/TrustProxies.php(57): Illuminate\Pipeline\Pipeline->Illuminate\Pipeline\{closure}() #35 /home/forge/gitapress.org/vendor/laravel/framework/src/Illuminate/Pipeline/Pipeline.php(171): Fideloper\Proxy\TrustProxies->handle() #36 /home/forge/gitapress.org/vendor/laravel/framework/src/Illuminate/Pipeline/Pipeline.php(105): Illuminate\Pipeline\Pipeline->Illuminate\Pipeline\{closure}() #37 /home/forge/gitapress.org/vendor/laravel/framework/src/Illuminate/Foundation/Http/Kernel.php(145): Illuminate\Pipeline\Pipeline->then() #38 /home/forge/gitapress.org/vendor/laravel/framework/src/Illuminate/Foundation/Http/Kernel.php(110): Illuminate\Foundation\Http\Kernel->sendRequestThroughRouter() #39 /home/forge/gitapress.org/public/index.php(55): Illuminate\Foundation\Http\Kernel->handle() #40 {main}