psr-0/4自动加载的后备位置

Question

I'm building a PHP package and in it I have a folder (let's say /vendor/myvendor/packagename/src/Classes ) which I want to autoload using PSR-4.

But I would also like to provide an option to copy that folder from its current location to the project root (let's say /packagename/Classes , something along the lines of Laravel's publish command).

So how could I go about autoloading it?

I would like Composer to first see if the folder exists under the app's root, and if it does then autoload that. Else fall back to the default location inside /vendor . Is that possible?

FWIW, this is Laravel specific package, which means that I could use Laravel's publish command to copy the entire folder where ever, but then

1. I would have to manually add the new location to autoload;
2. Even if I do, there would be namespace conflict between the old and new location.

Answer 1

I would like Composer to first see if the folder exists under the app's root, and if it does then autoload that. Else fall back to the default location inside /vendor. Is that possible?

Yes, it is possible.

You need to mention everything on your ServiceProvider for your package.

There are every informations about how to publish your views, assets in the docs and it fits your needs.

Have a look at the docs:

https://laravel.com/docs/5.3/packages#public-assets

I am copying some example for you over here:

If you want to publish your translations, you need to perform this task:

/**
 * Perform post-registration booting of services.
 *
 * @return void
 */
public function boot()
{
    $this->loadTranslationsFrom(__DIR__.'/path/to/translations', 'courier');

    $this->publishes([
        __DIR__.'/path/to/translations' => resource_path('lang/vendor/courier'),
    ]);
}

If you don't have translation in app's lang/vendor/courier then it falls back to your package translation.

You don't need to copy your class codes, which could remain in your package directory. The only things you copy will be your views, assets, translation files etc.

This should help you.