Brzmi skomplikowanie, ale idea jest prosta:<\/p>\n\n
\nzamiast tworzy\u0107 zale\u017cno\u015bci wewn\u0105trz klasy \u2014 przekazujesz je z zewn\u0105trz<\/p>\n<\/blockquote>\n\n
\n\n\u274c Problem bez Dependency Injection<\/h2>\n\n
class OrderService {
public function process() {
$payment = new StripePayment();
$payment->pay(100);
}
}<\/code><\/pre>\n\n\ud83d\udc49 problem:<\/p>\n\n
\n
- klasa jest \u201eprzyklejona\u201d do Stripe<\/li>\n\n\n\n
- ci\u0119\u017cko testowa\u0107<\/li>\n\n\n\n
- brak elastyczno\u015bci<\/li>\n<\/ul>\n\n
\n\n\u2705 Dependency Injection \u2014 rozwi\u0105zanie<\/h2>\n\n
class OrderService {
protected $payment;
public function __construct(PaymentInterface $payment) {
$this->payment = $payment;
}
public function process() {
$this->payment->pay(100);
}
}<\/code><\/pre>\n\n\ud83d\udc49 teraz:<\/p>\n\n
\n
- mo\u017cesz poda\u0107 dowoln\u0105 implementacj\u0119<\/li>\n\n\n\n
- klasa nie wie jak<\/em> dzia\u0142a p\u0142atno\u015b\u0107<\/li>\n\n\n\n
- jest bardziej elastyczna<\/li>\n<\/ul>\n\n
\n\n\ud83d\udd27 Jak dzia\u0142a to w Laravel?<\/h2>\n\n
Laravel ma wbudowany Service Container<\/strong>, kt\u00f3ry sam rozwi\u0105zuje zale\u017cno\u015bci.<\/p>\n\n
Przyk\u0142ad:<\/h3>\n\n
class OrderController extends Controller {
public function __construct(OrderService $orderService) {
$this->orderService = $orderService;
}
}<\/code><\/pre>\n\n\ud83d\udc49 Laravel automatycznie:<\/p>\n\n
\n
- tworzy
OrderService<\/code><\/li>\n\n\n\n- wstrzykuje zale\u017cno\u015bci<\/li>\n\n\n\n
- zarz\u0105dza cyklem \u017cycia obiekt\u00f3w<\/li>\n<\/ul>\n\n
\n\n\ud83d\udd25 Binding w Service Container<\/h2>\n\n
Cz\u0119sto u\u017cywasz interfejs\u00f3w:<\/p>\n\n
interface PaymentInterface {
public function pay(float $amount): void;
}<\/code><\/pre>\n\nImplementacja:<\/p>\n\n
class StripePayment implements PaymentInterface {
public function pay(float $amount): void {
\/\/ p\u0142atno\u015b\u0107
}
}<\/code><\/pre>\n\nRejestracja w Laravel:<\/h3>\n\n
app()->bind(PaymentInterface::class, StripePayment::class);<\/code><\/pre>\n\n\ud83d\udc49 teraz Laravel wie:<\/p>\n\n
\n
- jak\u0105 klas\u0119 podstawi\u0107 pod interfejs<\/li>\n<\/ul>\n\n
\n\n\ud83e\udde0 Typy Dependency Injection<\/h2>\n\n
1. Constructor Injection (najcz\u0119stsze)<\/h3>\n\n
public function __construct(Service $service)<\/code><\/pre>\n\n\ud83d\udc49 najlepsza opcja w 90% przypadk\u00f3w<\/p>\n\n
\n\n2. Method Injection<\/h3>\n\n
public function index(Service $service)<\/code><\/pre>\n\n\ud83d\udc49 u\u017cywane np. w kontrolerach<\/p>\n\n
\n\n3. Setter Injection (rzadziej)<\/h3>\n\n
public function setService(Service $service)<\/code><\/pre>\n\n\ud83d\udc49 mniej popularne<\/p>\n\n
\n\n\ud83d\udd25 Realny przyk\u0142ad (Laravel)<\/h2>\n\n
class ReportService {
public function generate() {
return \"raport\";
}
}
class ReportController extends Controller {
public function index(ReportService $reportService) {
return $reportService->generate();
}
}<\/code><\/pre>\n\n\ud83d\udc49 Laravel sam wstrzyknie
ReportService<\/code><\/p>\n\n
\n\n\ud83d\udca3 Dlaczego DI jest wa\u017cne?<\/h2>\n\n
\u2714 \u0142atwiejsze testowanie
\u2714 brak twardych zale\u017cno\u015bci
\u2714 lepsza architektura
\u2714 mo\u017cliwo\u015b\u0107 podmiany implementacji<\/p>\n\n
\n\n\ud83d\udca1 TL;DR<\/h2>\n\n
\n
- DI = przekazywanie zale\u017cno\u015bci zamiast tworzenia ich w klasie<\/li>\n\n\n\n
- Laravel robi to automatycznie<\/li>\n\n\n\n
- u\u017cywaj g\u0142\u00f3wnie constructor injection<\/li>\n<\/ul>\n\n
\n\n\ud83d\ude80 Podsumowanie<\/h2>\n\n
Dependency Injection to nie \u201epattern dla senior\u00f3w\u201d \u2014 to podstawowy spos\u00f3b pisania skalowalnego kodu.<\/p>\n\n
Je\u015bli u\u017cywasz Laravela i nie korzystasz z DI\u2026 to omijasz jedn\u0105 z jego najwi\u0119kszych zalet.<\/p>","protected":false},"excerpt":{"rendered":"","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"pagelayer_contact_templates":[],"_pagelayer_content":"","footnotes":""},"categories":[1],"tags":[],"class_list":["post-352","post","type-post","status-publish","format-standard","hentry","category-uncategorized"],"acf":[],"_links":{"self":[{"href":"https:\/\/piotrswitlicki.pl\/pl\/wp-json\/wp\/v2\/posts\/352","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/piotrswitlicki.pl\/pl\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/piotrswitlicki.pl\/pl\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/piotrswitlicki.pl\/pl\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/piotrswitlicki.pl\/pl\/wp-json\/wp\/v2\/comments?post=352"}],"version-history":[{"count":2,"href":"https:\/\/piotrswitlicki.pl\/pl\/wp-json\/wp\/v2\/posts\/352\/revisions"}],"predecessor-version":[{"id":354,"href":"https:\/\/piotrswitlicki.pl\/pl\/wp-json\/wp\/v2\/posts\/352\/revisions\/354"}],"wp:attachment":[{"href":"https:\/\/piotrswitlicki.pl\/pl\/wp-json\/wp\/v2\/media?parent=352"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/piotrswitlicki.pl\/pl\/wp-json\/wp\/v2\/categories?post=352"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/piotrswitlicki.pl\/pl\/wp-json\/wp\/v2\/tags?post=352"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}