When making money becomes a headache

When things go right and our product starts making money everyone is happy, but sometimes this means the start of the nightmare for people working with payments.

Let's not sugar coat it. In this talk you'll learn about some where thing went terribly wrong, some of them involved loosing money. Stories of stuff that can easily get overlooked, about the most common mistakes when working with payments and things you probably won't consider until shit hits the fan. All of this so that you don't run into the same problems and don't have to learn those lessons the hard way.

Presented at: wroc_love.rb 2016

Transcript

1. Dealing with payments
2. Sebastián Sogamoso @sebasoga
5. Story time
6. When making money becomes a ache head
10. Requirements
11. Payment gateway
12. Our system
13. Our system
14. Our system Payment Gateway
15. Our system Payment Gateway
16. Our system Payment Gateway Payment Processor
17. Our system Payment Gateway Payment Processor 1 Payment Processor 2
18. Our system Payment Gateway Payment Processor
19. Our system Payment Gateway Payment Processor
20. Our system Payment Gateway Payment Processor Card’s Brand
21. Our system Payment Gateway Payment Processor Card Issuing Bank Marchant’s Bank Card’s Brand
22. Our system Payment Gateway Marchant’s Bank
23. Our system Payment Gateway
26. Product launch
27. Not quite as fast
28. Not quite as fast Requests timeout
29. Not quite as fast Requests timeout Background workers to the rescue
30. Client’s browser Web application
31. Client’s browser Web application Background Worker
32. Client’s browser Web application Background Worker
33. Client’s browser Web application Background Worker Creates the user Payment Gateway
34. Client’s browser Web application Background Worker Background Worker Payment Gateway Add card to user
35. Client’s browser Web application Background Worker Background Worker Payment Gateway Charges user Background Worker
37. Atomic operations
38. ActiveRecord.transaction do company.charge(price + fee) computer_owner.pay(price) end
39. PaymentGateway.transaction do renter.charge!(amount: 120) owner.pay!(amount: 100) end
41. to a 3rd party Coupling
42. Adapter pattern
43. Business Logic Payment Gateway Logic
44. Business Logic Payment Gateway 1 Payment Gateway 2
45. Business Logic Payment Gateway 1 Payment Gateway 2
47. Payment gateway Own system Pay user Ok
48. Payment gateway Own system Pay user Ok Payment result Ok
51. Monitoring & Alerts
52. Current state & History
54. @sebasoga Thanks!