Override Singleton in Laravel Container - php

Question

I'm wondering if there's a simple way to override a singleton service set in the core of the Laravel framework?
e.g. I'm trying to rewrite the app:name command service '' with the following provider:
use Hexavel\Console\AppNameCommand;
use Illuminate\Console\Events\ArtisanStarting;
use Illuminate\Contracts\Events\Dispatcher;
use Illuminate\Support\ServiceProvider;
class NameCommandProvider extends ServiceProvider
{
/**
* Register any other events for your application.
*
* #param \Illuminate\Contracts\Events\Dispatcher $events
* #return void
*/
public function boot(Dispatcher $events)
{
$events->listen(ArtisanStarting::class, function ($event) {
$event->artisan->resolve('command.app.name');
}, -1);
}
/**
* Register the service provider.
*
* #return void
*/
public function register()
{
$this->app->singleton('command.app.name', function ($app) {
return new AppNameCommand($app['composer'], $app['files']);
});
}
}
I'm 100% everything is working due to extensive checks put no matter what order I put my service provider (above or below ConsoleSupportServiceProvider) it still loads the original AppNameCommand over my custom one.
I've already got a work around BUT it would be nice to know about the behaviour of singleton services for the future if this is at all possible? (This is using Laravel 5.2 if that makes any difference.)

Answer 1

There's actually a cleaner way to do this. You basically want to extend a core binding, which can be achieved by using the extend method:
$this->app->extend('command.app.name', function ($command, $app) {
return new AppNameCommand($app['composer'], $app['files']);
});
Jason Lewis has a really nice article regarding Laravel's IoC on Tutsplus. Make sure to check it out ;)

Answer 2

I looked at this case and it seems it not the easy one. If you use singleton in your custom Provider it will be finally overridden by default provider (deferred one) so it seems it won't be the way.
After checking that simple approach doesn't work, what you need to do in such case is analysing what is happening when Laravel registers this command.
So in your case you search first for command.app.name - you see it's in Illuminate\Foundation\Providers\ArtisanServiceProvider and there is method registerAppNameCommand you would like to probably override.
So now you look for occurences of ArtisanServiceProvider to see where it's launched - you see it's in Illuminate\Foundation\Providers\ConsoleSupportServiceProvider in $providers property (which you would like probably to change).
So finally you should look for occurrences of ConsoleSupportServiceProvider and you see it's in config/app.php.
So what you need to do in this case:
Change in config/app.php - change Illuminate\Foundation\Providers\ConsoleSupportServiceProvider into your custom one ConsoleSupportServiceProvider
In your custom one you should extend from \Illuminate\Foundation\Providers\ConsoleSupportServiceProvider but change in $providers from Illuminate\Foundation\Providers\ArtisanServiceProvider into your custom ArtisanServiceProvider
finally create custom ArtisanServiceProvider which will extend from \Illuminate\Foundation\Providers\ArtisanServiceProvider where you override registerAppNameCommand using custom class in singleton
Using this way you will achieve your goal (I've verified it that custom class will be used running command php artisan app:name).
Alternatively you might want in your custom ArtisanServiceProvider remove 'AppName' => 'command.app.name', from $devCommands and use your custom service provider as you showed where you register your singleton but I haven't tried this approach.