服務提供者

• 概述
• Create Service Provider
• Dependency Relationship
• Runners

概述

內核啟動操作中最重要的事情是加載 ServiceProvider。 All ServiceProvider under the application are configured in the bootstrap/providers.go file.

首先，內核會調用所有服務提供者的 Register 方法。 在所有服務提供者註冊後，內核將再次調用所有 ServiceProvider 的 Boot 方法。

ServiceProvider 是 Goravel 生命週期的關鍵。 它們使框架能夠包含各種組件，例如路由、數據庫、隊列、快取等。

Create Service Provider

Service providers contain a Register and a Boot method. Within the Register method, you should only bind things into the service container. You should never attempt to register any event listeners, routes, or any other piece of functionality within the Register method, use the Boot method for that.

./artisan make:provider YourServiceProviderName

The Artisan CLI can generate a new provider via the make:provider command. The new service provider will be registered automatically in the bootstrap/providers.go::Providers() function and the function will be called by WithProviders.

func Boot() contractsfoundation.Application {
	return foundation.Setup().
		WithProvders(Providers).
		WithConfig(config.Boot).
		Create()
}

Dependency Relationship

ServiceProvider provides an optional method Relationship() binding.Relationship, used to declare the dependency relationship, the ServiceProvider that sets this method will not depend on the registration order, and the ServiceProvider that does not set it will be registered last, for example:

type ServiceProvider struct {}

func (r *ServiceProvider) Relationship() binding.Relationship {
	return binding.Relationship{
		Bindings: []string{
			"custom",
		},
		Dependencies: []string{
			binding.Config,
		},
		ProvideFor: []string{
			binding.Cache,
		},
	}
}

func (r *ServiceProvider) Register(app foundation.Application) {
	app.Singleton("custom", func(app foundation.Application) (any, error) {
		return New()
	})
}

func (r *ServiceProvider) Boot(app foundation.Application) {}

Runners

The ServiceProvider can also implement the Runners interface to run some code when the application starts. It's usually used to start/shutdown the service which is defined in the ServiceProvider. For example: Route, Schedule, Queue, etc. You don't need to start/shutdown these services with Runners in the main.go anymore, Goravel will take care of it.

A Runner contains three methods: ShouldRun(), Run(), and Shutdown().

type Runner interface {
	// ShouldRun determines whether the runner should be executed.
	ShouldRun() bool
	// Run starts the runner.
	Run() error
	// Shutdown gracefully stops the runner.
	Shutdown() error
}

There is an example of a RouteRunner defined in the ServiceProvider to start and shutdown the Route service.

type ServiceProvider struct {}

func (r *ServiceProvider) Register(app foundation.Application) {}

func (r *ServiceProvider) Boot(app foundation.Application) {}

func (r *ServiceProvider) Runners(app foundation.Application) []foundation.Runner {
	return []foundation.Runner{NewRouteRunner(app.MakeConfig(), app.MakeRoute())}
}

package route

import (
	"github.com/goravel/framework/contracts/config"
	"github.com/goravel/framework/contracts/route"
)

type RouteRunner struct {
	config config.Config
	route  route.Route
}

func NewRouteRunner(config config.Config, route route.Route) *RouteRunner {
	return &RouteRunner{
		config: config,
		route:  route,
	}
}

func (r *RouteRunner) ShouldRun() bool {
	return r.route != nil && r.config.GetString("http.default") != ""
}

func (r *RouteRunner) Run() error {
	return r.route.Run()
}

func (r *RouteRunner) Shutdown() error {
	return r.route.Shutdown()
}

You can register your own Runner in the bootstrap/app.go::WithRunners function to run some code when the application starts.

func Boot() contractsfoundation.Application {
	return foundation.Setup().
		WithConfig(config.Boot).
		WithRunners(func() []foundation.Runner{
			return []foundation.Runner{
				NewYourCustomRunner(),
			}
		}).
		Create()
}