Welcome to the (state) machine @ Xe One Day Enterprise Applications
•Télécharger en tant que PPTX, PDF•
0 j'aime•275 vues
Ultimamente ci hanno stressato come non mai che stateful è il male. Tutto deve essere stateless, altrimenti non scala, non può essere altamente disponibile, ed è complesso da manutenere ed evolvere. Nonostante questo i sistemi software complessi, essendo basati su processi collaborativi, sono per natura stateful. I processi collaborativi, noti anche come long running business transactions, necessitano di interagiscono con risorse distribuite. L’approccio tradizionale basato su transazioni distribuite, anche se allettante, è una bomba pronta ad esplodere. Pane quotidiano per le Saghe. Le Saghe consentono di modellare sistemi complessi senza la necessità di transazioni distribuite e coordinamento esterno. Vedremo cosa sono le Saghe, come possono essere usate per modellare domini complessi, e che ruolo giocano quando progettiamo sistemi basati sui concetti di “design for failures” e “eventual consistency” (It’s all right, I know where you’ve been)
Recommandé
Recommandé
Contenu connexe
Similaire à Welcome to the (state) machine @ Xe One Day Enterprise Applications
Similaire à Welcome to the (state) machine @ Xe One Day Enterprise Applications (12)
Plus de Mauro Servienti
Plus de Mauro Servienti (20)
Dernier
Dernier (20)
Welcome to the (state) machine @ Xe One Day Enterprise Applications
- 1. #XeOneDay Evento realizzato grazie al supporto di
- 2. welcome to the (state) machine It’s all right, I know where you’ve been mauroservienti Mauro Servienti
- 3. All I want to do when I wake up in the morning is… (cit. Rosanna, Toto, Toto IV) mauroservienti
- 5. buy ticket(s) stage dive… :-) mauroservienti
- 6. All what they want to do is… mauroservienti
- 8. display available tickets reserve ticket(s) charge my credit card deal with insurance ship ticket(s) deal with their stuff mauroservienti
- 9. sometimes order doesn’t matter sometimes it does! mauroservienti
- 10. Process Manager Connecting the dots… mauroservienti
- 11. Tickets Selection Credit Card Gateway/ACL Orders Manager Checkout request AuthorizeCard request/response Reservation Gateway/ACL ConfirmTickets request/response Credit Card Gateway/ACL ChargeCard request/response Insurance Gateway/ACL TicketsInsurance request/response Shipping Gateway/ACL Shiptickets request/response 2-phase commit (kind-of) … mauroservienti Reservation Gateway/ACL SelectTickets request/response
- 12. Process Manager (a different point of view) New requirement: collect tickets at the venue OrderId ShippingId ShippingStatus Etc 12 1337 Delivered … 58 1338 Pending … Orders table mauroservienti
- 13. mauroservienti like a Punch Card, a Process Manager owns the process
- 15. Process Managers, a source of coupling •Violates Single Responsibility Principle •Contention/Performance Bottleneck •Conflicting Changes/Merge Conflicts •Single Unit of Deployment •Single Point of Failure mauroservienti
- 16. user mental model tends to be UI driven mauroservienti
- 17. there is no Spoon Orders Manager mauroservienti
- 20. sagas autonomy in collaborative domains mauroservienti
- 21. multiple workflows, each providing compensating actions for every step of the workflow where it can fail mauroservienti
- 22. multiple workflows, each providing compensating actions for every step of the workflow where it can fail mauroservienti
- 23. reserve with the theater charge my credit card deal with insurance ship tickets deal with their stuff mauroservienti
- 25. Shipping Finance Tickets Ordering Saga mauroservienti ReservationOrder Checked-out Payment Authorized Order Created Payment Succeeded Available Tickets Select tickets Shopping Cart Proceed to checkout workflow workflow workflow
- 26. Shipping Finance Tickets Ordering Saga mauroservienti ReservationOrder Checked-out Payment Authorized Order Created Payment Succeeded Available Tickets Select tickets Shopping Cart Proceed to checkout Policy Policy Policy
- 27. Shipping Finance mauroservienti Reservation Available Tickets Select tickets Shopping Cart Proceed to checkout Policy Policy Policy Order Checked-out Payment Authorized Order Created Payment Succeeded Pivotal Events
- 28. mauroservienti Let’s open the black box
- 29. Shipping ReservationPayment Gateway Finance Finance Initiate Payment Authorize Card Courier Gateway Tickets Ordering Saga mauroservienti Available Tickets Select tickets Reservation Shopping Cart Proceed to checkout Reservation Order Checked-out Payment Authorized Order CreatedFinance Payment Gateway Charge Card Payment Succeeded Delivery Pick-up Order Shipped
- 30. multiple workflows, each providing compensating actions for every step of the workflow where it can fail mauroservienti
- 31. Shipping ReservationPayment Gateway Finance Finance Initiate Payment Authorize Card Courier Gateway Tickets Ordering Saga mauroservienti Available Tickets Select tickets Reservation Shopping Cart Proceed to checkout Reservation Order Checked-out Payment Authorized Order CreatedFinance Payment Gateway Charge Card Payment Succeeded Delivery Pick-up Order Shipped
- 32. Payment Gateway Finance Finance Initiate Payment Authorize Card Payment Policy mauroservienti Order Checked-out Payment Authorized Finance Payment Gateway Charge Card Payment Succeeded
- 33. Payment Gateway Finance Finance Initiate Payment Authorize Card Payment Policy mauroservienti Order Checked-out Payment Authorized 48hrs to release money
- 34. Payment Gateway Finance Finance Initiate Payment Authorize Card Payment Policy mauroservienti Order Checked-out Payment Authorized Finance Payment Gateway Charge Card Payment Succeeded 48hrs to release money Payment Gateway Release Money Reserved?N Y Do nothing… Reservation Order Created 48hrs later…
- 35. New requirement • A ticket must be purchased within 10 minutes mauroservienti
- 36. Shipping ReservationPayment Gateway Finance Finance Initiate Payment Authorize Card Courier Gateway Tickets Ordering Saga mauroservienti Available Tickets Select tickets Reservation Shopping Cart Proceed to checkout Reservation Order Checked-out Payment Authorized Order CreatedFinance Payment Gateway Charge Card Payment Succeeded Delivery Pick-up Order Shipped
- 37. Reservation Reservation Policy mauroservienti Available Tickets Select tickets Reservation Tickets Reserved 10’ to purchase Reservation Release Tickets N Y Do nothing… Checked-out?Reservation Expired
- 38. Shipping ReservationPayment Gateway Finance Finance Initiate Payment Authorize Card Courier Gateway Tickets Ordering Saga mauroservienti Available Tickets Select tickets Reservation Tickets Added to Cart Reservation Shopping Cart Proceed to checkout Reservation Order Checked-out Payment Authorized Order CreatedFinance Payment Gateway Charge Card Payment Succeeded Delivery Pick-up Order Shipped 10’ to purchase 48hrs to release money
- 39. New requirement • 12-hours delivery SLA with our customers • if the default shipping courier doesn't respond • contact another one to deliver the package mauroservienti
- 40. Shipping ReservationPayment Gateway Finance Finance Initiate Payment Authorize Card Courier Gateway Shipping Policy mauroservienti Available Tickets Select tickets Reservation Tickets Added to Cart Reservation Shopping Cart Proceed to checkout Reservation Order Checked-out Payment Authorized Order CreatedFinance Payment Gateway Charge Card Payment Succeeded Delivery Pick-up Order Shipped 10’ to purchase 48hrs to release money
- 41. Shipping Order Shipped … First Courier Gateway Pick-up Request Shipping Shipping Second Courier Gateway Pick-up Request Shipping Shipping Have we received a response? Shipment Failed … mauroservienti 8hrs timeout Shipping Policy Have we received a response? ? 2hrs escalation timeout N N?Y Y
- 42. Concurrency 1. Pick-up request to 1st courier 2. 8 hours go by 3. No response yet 4. Pick-up request to 2nd courier 5. 2nd courier replies 6. 1st courier replies…Ooops mauroservienti
- 43. mauroservienti It’s a business problem
- 44. Sagas (a different point of view) OrderId ShippingId ShippingStatus Etc 12 1337 Delivered … 58 1338 Pending … Orders table Reservation Shipping Finance Id TicketId 12 ABC 58 ACD Reservations table OrderId Address 12 Haifa, Israel 58 Rotterdam, Holland Shipping table OrderId Status 12 Paid 58 Overdue Invoices table VS mauroservienti
- 45. Sagas (a different point of view) Reservation Shipping Finance Id TicketId 12 ABC 58 ACD Reservations table OrderId Address 12 Haifa, Israel 58 Rotterdam, Holland Shipping table OrderId Status 12 Paid 58 Overdue Invoices table mauroservienti Each service can evolve independently
- 46. Sagas •Business Process is distributed •No overarching Process Manager •Respect Single Responsibility Principle •Independent scale out •Simpler/not conflicting evolution •Independent Units of Deployment mauroservienti
- 47. Every year is getting shorter never seem to find the time… Sagas Demo bit.ly/xe-state-machine Udi Dahan about Sagas go.particular.net/xe-state-machine mauroservienti
- 48. Demos: bit.ly/xe-state-machine Videos: go.particular.net/xe-state-machine Pitfalls • Monitor the (distributed) state mauroservienti
- 49. Demos: bit.ly/xe-state-machine Videos: go.particular.net/xe-state-machine Pitfalls • Monitor the (distributed) state • There is no such thing as orchestration • Sagas spanning multiple services mauroservienti
- 50. Demos: bit.ly/xe-state-machine Videos: go.particular.net/xe-state-machine Takeaways • Boundaries are key to success • Finding boundaries is the hardest part mauroservienti
- 51. Demos: bit.ly/xe-state-machine Videos: go.particular.net/xe-state-machine Takeaways • Boundaries are key to success • Behaviors define how to designs processes • Follow the coupling, not the data • Identify processes and chop them up by “service” mauroservienti
- 52. Demos: bit.ly/xe-state-machine Videos: go.particular.net/xe-state-machine Takeaways • Boundaries are key to success • Behaviors define how to designs processes • Use Delayed Messaging to model time • Simplifies making decisions in an async world mauroservienti
- 53. @mauroservienti | #EDDD Mauro Servienti Solution Architect @ Particular Software the makers of NServiceBus mauro.servienti@particular.net @mauroservienti //github.com/mauroservienti //milestone.topics.it mauroservienti
- 54. @mauroservienti | #EDDD Demos: bit.ly/xe-state-machine Videos: go.particular.net/xe-state-machine mauroservienti
Notes de l'éditeur
- Ritmo tribale Litfiba
- Let me tell that you of that time when {the vendor I cannot name} gifted me with a nice {flat x86 device with a very thin keyboard} {the story} It’s obvious that there are two very different point of views here.
- Quick detour on the overall complexity
- No scatter/gather Too many messages
- No scatter/gather Too many messages