To upgrade your application to Laravel 4.1, change your laravel/framework version to 4.1.* in your composer.json file.
Replace your public/index.php file with this fresh copy from the repository.
Replace your artisan file with this fresh copy from the repository.
Update your aliases and providers arrays in your app/config/app.php configuration file. The updated values for these arrays can be found in this file. Be sure to add your custom and package service providers / aliases back to the arrays.
Add the new app/config/remote.php file from the repository.
Add the new expire_on_close configuration option to your app/config/session.php file. The default value should be false.
Add the new failed configuration section to your app/config/queue.php file. Here are the default values for the section:
'failed' => array(
'database' => 'mysql', 'table' => 'failed_jobs',
),
(Optional) Update the pagination configuration option in your app/config/view.php file to pagination::slider-3.
If app/controllers/BaseController.php has a use statement at the top, change use Illuminate\Routing\Controllers\Controller; to use Illuminate\Routing\Controller;.
Password reminders have been overhauled for greater flexibility. You may examine the new stub controller by running the php artisan auth:reminders-controller Artisan command. You may also browse the updated documentation and update your application accordingly.
Update your app/lang/en/reminders.php language file to match this updated file.
For security reasons, URL domains may no longer be used to detect your application environment. These values are easily spoofable and allow attackers to modify the environment for a request. You should convert your environment detection to use machine host names (hostname command on Mac & Ubuntu).
Laravel now generates a single log file: app/storage/logs/laravel.log. However, you may still configure this behavior in your app/start/global.php file.
In your bootstrap/start.php file, remove the call to $app->redirectIfTrailingSlash(). This method is no longer needed as this functionality is now handled by the .htaccess file included with the framework.
Next, replace your Apache .htaccess file with this new one that handles trailing slashes.
The current route is now accessed via Route::current() instead of Route::getCurrentRoute().
Once you have completed the changes above, you can run the composer update function to update your core application files! If you receive class load errors, try running the update command with the --no-scripts option enabled like so: composer update --no-scripts.