Package Development
Introduction
Packages are the primary way of adding functionality to Laravel. Packages might be anything from a great way to work with dates like Carbon, or an entire BDD testing framework like Behat.
Of course, there are different types of packages. Some packages are stand-alone, meaning they work with any PHP framework. Carbon and Behat are examples of stand-alone packages. Any of these packages may be used with Laravel by simply requesting them in your composer.json
file.
On the other hand, other packages are specifically intended for use with Laravel. These packages may have routes, controllers, views, and configuration specifically intended to enhance a Laravel application. This guide primarily covers the development of those packages that are Laravel specific.
A Note On Facades
When writing a Laravel application, it generally does not matter if you use contracts or facades since both provide essentially equal levels of testability. However, when writing packages, it is best to use contracts instead of facades. Since your package will not have access to all of Laravel's testing helpers, it will be easier to mock or stub a contract than to mock a facade.
Service Providers
Service providers are the connection points between your package and Laravel. A service provider is responsible for binding things into Laravel's service container and informing Laravel where to load package resources such as views, configuration, and localization files.
A service provider extends the Illuminate\Support\ServiceProvider
class and contains two methods: register
and boot
. The base ServiceProvider
class is located in the illuminate/support
Composer package, which you should add to your own package's dependencies. To learn more about the structure and purpose of service providers, check out their documentation.
Routing
To define routes for your package, pass the routes file path to the loadRoutesFrom
method from within your package service provider's boot
method. From within your routes file, you may use the Illuminate\Support\Facades\Route
facade to register routes just as you would within a typical Laravel application:
/**
* Perform post-registration booting of services.
*
* @return void
*/
public function boot()
{
$this->loadRoutesFrom(__DIR__.'/path/to/routes.php');
}
Resources
Configuration
Typically, you will need to publish your package's configuration file to the application's own config
directory. This will allow users of your package to easily override your default configuration options. To allow your configuration files to be published, call the publishes
method from the boot
method of your service provider:
/**
* Perform post-registration booting of services.
*
* @return void
*/
public function boot()
{
$this->publishes([
__DIR__.'/path/to/config/courier.php' => config_path('courier.php'),
]);
}
Now, when users of your package execute Laravel's vendor:publish
command, your file will be copied to the specified publish location. Of course, once your configuration has been published, its values may be accessed like any other configuration file:
$value = config('courier.option');
{note} You should not define Closures in your configuration files. They can not be serialized correctly when users execute the
config:cache
Artisan command.
Default Package Configuration
You may also merge your own package configuration file with the application's published copy. This will allow your users to define only the options they actually want to override in the published copy of the configuration. To merge the configurations, use the mergeConfigFrom
method within your service provider's register
method:
/**
* Register bindings in the container.
*
* @return void
*/
public function register()
{
$this->mergeConfigFrom(
__DIR__.'/path/to/config/courier.php', 'courier'
);
}
{note} This method only merges the first level of the configuration array. If your users partially define a multi-dimensional configuration array, the missing options will not be merged.
Migrations
If your package contains database migrations, you may use the loadMigrationsFrom
method to inform Laravel how to load them. The loadMigrationsFrom
method accepts the path to your package's migrations as its only argument:
/**
* Perform post-registration booting of services.
*
* @return void
*/
public function boot()
{
$this->loadMigrationsFrom(__DIR__.'/path/to/migrations');
}
Once your package's migrations have been registered, they will automatically be run when the php artisan migrate
command is executed. You do not need to export them to the application's main database/migrations
directory.
Translations
If your package contains translation files, you may use the loadTranslationsFrom
method to inform Laravel how to load them. For example, if your package is named courier
, you should add the following to your service provider's boot
method:
/**
* Perform post-registration booting of services.
*
* @return void
*/
public function boot()
{
$this->loadTranslationsFrom(__DIR__.'/path/to/translations', 'courier');
}
Package translations are referenced using the package::file.line
syntax convention. So, you may load the courier
package's welcome
line from the messages
file like so:
echo trans('courier::messages.welcome');
Publishing Translations
If you would like to publish your package's translations to the application's resources/lang/vendor
directory, you may use the service provider's publishes
method. The publishes
method accepts an array of package paths and their desired publish locations. For example, to publish the translation files for the courier
package, you may do the following:
/**
* 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'),
]);
}
Now, when users of your package execute Laravel's vendor:publish
Artisan command, your package's translations will be published to the specified publish location.
Views
To register your package's views with Laravel, you need to tell Laravel where the views are located. You may do this using the service provider's loadViewsFrom
method. The loadViewsFrom
method accepts two arguments: the path to your view templates and your package's name. For example, if your package's name is courier
, you would add the following to your service provider's boot
method:
/**
* Perform post-registration booting of services.
*
* @return void
*/
public function boot()
{
$this->loadViewsFrom(__DIR__.'/path/to/views', 'courier');
}
Package views are referenced using the package::view
syntax convention. So, once your view path is registered in a service provider, you may load the admin
view from the courier
package like so:
Route::get('admin', function () {
return view('courier::admin');
});
Overriding Package Views
When you use the loadViewsFrom
method, Laravel actually registers two locations for your views: the application's resources/views/vendor
directory and the directory you specify. So, using the courier
example, Laravel will first check if a custom version of the view has been provided by the developer in resources/views/vendor/courier
. Then, if the view has not been customized, Laravel will search the package view directory you specified in your call to loadViewsFrom
. This makes it easy for package users to customize / override your package's views.
Publishing Views
If you would like to make your views available for publishing to the application's resources/views/vendor
directory, you may use the service provider's publishes
method. The publishes
method accepts an array of package view paths and their desired publish locations:
/**
* Perform post-registration booting of services.
*
* @return void
*/
public function boot()
{
$this->loadViewsFrom(__DIR__.'/path/to/views', 'courier');
$this->publishes([
__DIR__.'/path/to/views' => resource_path('views/vendor/courier'),
]);
}
Now, when users of your package execute Laravel's vendor:publish
Artisan command, your package's views will be copied to the specified publish location.
Commands
To register your package's Artisan commands with Laravel, you may use the commands
method. This method expects an array of command class names. Once the commands have been registered, you may execute them using the Artisan CLI:
/**
* Bootstrap the application services.
*
* @return void
*/
public function boot()
{
if ($this->app->runningInConsole()) {
$this->commands([
FooCommand::class,
BarCommand::class,
]);
}
}
Public Assets
Your package may have assets such as JavaScript, CSS, and images. To publish these assets to the application's public
directory, use the service provider's publishes
method. In this example, we will also add a public
asset group tag, which may be used to publish groups of related assets:
/**
* Perform post-registration booting of services.
*
* @return void
*/
public function boot()
{
$this->publishes([
__DIR__.'/path/to/assets' => public_path('vendor/courier'),
], 'public');
}
Now, when your package's users execute the vendor:publish
command, your assets will be copied to the specified publish location. Since you will typically need to overwrite the assets every time the package is updated, you may use the --force
flag:
php artisan vendor:publish --tag=public --force
Publishing File Groups
You may want to publish groups of package assets and resources separately. For instance, you might want to allow your users to publish your package's configuration files without being forced to publish your package's assets. You may do this by "tagging" them when calling the publishes
method from a package's service provider. For example, let's use tags to define two publish groups in the boot
method of a package service provider:
/**
* Perform post-registration booting of services.
*
* @return void
*/
public function boot()
{
$this->publishes([
__DIR__.'/../config/package.php' => config_path('package.php')
], 'config');
$this->publishes([
__DIR__.'/../database/migrations/' => database_path('migrations')
], 'migrations');
}
Now your users may publish these groups separately by referencing their tag when executing the vendor:publish
command:
php artisan vendor:publish --tag=config