Better Code Design in PHP

Are you tired of spending hours reading code just to find the right place to make a small change? Are you forced to split your application into several just so that devs don't step on each other's toes? This talk unites theory with practice to show you how to structure your code so that it is easy to read, to test and to maintain. You will step out with concrete ideas of how to improve your code design.

Transcript

1. Better Code Design in PHP BETTERCODE() 2023 | ONLINE @afilina@phpc.social
2. Anna Filina • Coding since 1997. • PHP, Java, C#, etc. • Legacy archaeology. • Test automation. • Talks and workshops. • YouTube videos. • Filina Consulting.
4. Object Mutual reference Collaborator
5. Object One-way reference Collaborator
6. Object Chatty Collaborator Step 1 Step 2 Step 3
7. Object Less chatty Collaborator Task Step 1 Step 2 Step 3
8. Is the complexity justified? Object 1 Object 2 Object 3 Object 4 Bus
9. Design Drive • Avoid complexity until I need it. • Do I understand what’s going on in terms of the business use case?
11. Objects should speak business, not technical.
12. $lineItems = $this->orders->getLineItems($pendingOrderNumber); $taxTotals = $this->taxes->calculateForLineItems($lineItems);
13. Project • Marketplace for short-term rental: • Search properties for rent by city, date and number of guests. • Reserve & pay.
14. ReservationService ::reserve() PaymentManager ReservationManager processPayment(data) Templating saveReservation(data) confirmReservation(data) html EmailManager payment savePayment(data) confirmReservation(html)
15. ReservationService ::reserve() PaymentManager ReservationManager processPayment(data) Templating saveReservation(data) confirmReservation(data) html EmailManager payment savePayment(data) confirmReservation(html)
16. MakeReservation ReservationRepository add(paidReservation) ReservationNotifier PaymentProcessor capture(charge) paymentConfirmation notifyBuyer(paidReservation)
17. MakeReservation ReservationRepository add(paidReservation) ReservationNotifier PaymentProcessor capture(charge) paymentConfirmation notifyBuyer(paidReservation)
18. MakeReservation ReservationRepository add(paidReservation) ReservationNotifier PaymentProcessor capture(charge) paymentConfirmation notifyBuyer(paidReservation)
19. MakeReservation ReservationRepository add(paidReservation) notifyBuyer(paidReservation) ReservationNotifier PaymentProcessor capture(charge) paymentConfirmation
20. MakeReservation ReservationRepository add(paidReservation) ReservationNotifier PaymentProcessor capture(charge) paymentConfirmation notifyBuyer(paidReservation)
21. Good design needs no diagrams.
24. Simple Code • No need for framework. • No need to design the database. • No need to have a UI. • Code the business rules.
26. Handle HTTP Request Return HTTP Response 2 adults in Lviv on Jan 1 to Jan 7 Results containing “Lviv for 4”
28. Handle HTTP Request Return HTTP Response 2 adults in Lviv on Jan 1 to Jan 7 Results containing “Lviv for 4”
34. A complex system that works is invariably found to have evolved from a simple system that worked. — John Gall
36. Too reusable becomes unusable.
39. Input/output Business rules Infrastructure Use case
51. PropertySearchHandler Lviv, Lviv Oblast, Ukraine Validate anyway. Convert to coordinates. CitySearchHandler Lviv Lviv, Lviv Oblast, Ukraine Lviv Boulevard, Oshawa, ON
53. PropertySearchHandler 49.8397, 24.0297 Longitude: -180 to +180 Latitude: -90 to +90 CitySearchHandler Lviv Lviv, Lviv Oblast, Ukraine 49.8397 24.0297
55. Code is simply a model of the business rules and knowledge.
56. @afilina@phpc.social