Skinny dipping into CQRS

Transcript

1. SKINNY DIPPING INTO CQRS A QUICK INTRO Created by / Warnar Boekkooi @boekkooi
2. WHAT IS CQRS? COMMAND QUERY RESPONSIBILITY SEGREGATION
3. WHAT CAN CQRS DO FOR YOU? Capture intent Easy to Scale Domain-Driven Design Task based UI Headache
4. WHERE YOU ARE... CRUD Create Read Update Delete
5. ARCHITECTURE * Thanks to for the image Martin Fowler
6. MODEL c l a s s A p p o i n t m e n t { f u n c t i o n s e t T i t l e ( $ t i t l e ) { . . . } f u n c t i o n g e t T i t l e ( ) { . . . } f u n c t i o n s e t S t a r t ( \ D a t e T i m e $ d a t e ) { . . . } f u n c t i o n g e t S t a r t ( ) { . . . } f u n c t i o n s e t D u r a t i o n ( $ d u r a t i o n ) { . . . } f u n c t i o n g e t D u r a t i o n ( ) { . . . } f u n c t i o n s e t L o c a t i o n ( $ l o c a t i o n ) { . . . } f u n c t i o n g e t L o c a t i o n ( ) { . . . } }
7. SERVICE c l a s s A p p o i n t m e n t S e r v i c e { f u n c t i o n u p d a t e ( $ a p p o i n t m e n t I d , $ t i t l e , $ s t a r t , $ d u r a t i o n , $ l o c a t i o n ) { $ a p p o i n t m e n t = $ t h i s - > r e p o - > f i n d B y I d ( $ a p p o i n t m e n t I d ) ; i f ( ! $ a p p o i n t m e n t ) { t h r o w n e w N o t F o u n d E x c e p t i o n ( ) ; } $ a p p o i n t m e n t - > s e t T i t l e ( $ t i t l e ) ; $ a p p o i n t m e n t - > s e t S t a r t ( $ s t a r t ) ; $ a p p o i n t m e n t - > s e t D u r a t i o n ( $ d u r a t i o n ) ; $ a p p o i n t m e n t - > s e t L o c a t i o n ( $ l o c a t i o n ) ; $ t h i s - > r e p o - > s a v e ( $ a p p o i n t m e n t ) ; } }
8. ANEMIC DOMAIN “There are objects, many named after the nouns in the domain space, and these objects are connected with the rich relationships and structure that true domain models have. The catch comes when you look at the behavior, and you realize that there is hardly any behavior on these objects, making them little more than bags of getters and setters.”
9. WHERE TO GO... COMMAND QUERY RESPONSIBILITY SEGREGATION
10. ARCHITECTURE * Thanks to for the image Martin Fowler
11. TIME TO COMMAND CREATE APPOINTMENT RegisterAppointmentCommand UPDATE APPOINTMENT RelocateAppointmentCommand RescheduleAppointmentCommand REMOVE APPOINTMENT CancelAppointmentCommand
12. A COMMAND c l a s s R e l o c a t e A p p o i n t m e n t C o m m a n d { p u b l i c $ a p p o i n t m e n t I d ; p u b l i c $ l o c a t i o n ; }
13. TIME TO SEPARATE c l a s s A p p o i n t m e n t M o d e l { f u n c t i o n r e g i s t e r ( $ c o m m a n d ) { . . . } f u n c t i o n r e l o c a t e ( $ c o m m a n d ) { . . . } f u n c t i o n r e s c h e d u l e ( $ c o m m a n d ) { . . . } f u n c t i o n c a n c e l ( $ c o m m a n d ) { . . . } } c l a s s A p p o i n t m e n t V i e w { f u n c t i o n g e t T i t l e ( ) { . . . } f u n c t i o n g e t L o c a t i o n ( ) { . . . } f u n c t i o n g e t S t a r t ( ) { . . . } f u n c t i o n g e t D u r a t i o n ( ) { . . . } }
14. HANDLE A COMMAND c l a s s A p p o i n t m e n t H a n d l e r { f u n c t i o n h a n d l e R e l o c a t e A p p o i n t m e n t ( $ c o m m a n d ) { $ a p p o i n t m e n t = $ t h i s - > r e p o s i t o r y - > f i n d B y I d ( $ c o m m a n d - > a p p o i n t m e n t I d ) ; $ a p p o i n t m e n t - > r e l o c a t e ( $ c o m m a n d ) ; } } c l a s s C o m m a n d B u s { f u n c t i o n e x e c u t e ( $ c o m m a n d ) { $ t h i s - > v a l i d a t o r - > v a l i d a t e ( $ c o m m a n d ) ; $ t h i s - > d i s p a t c h ( $ c o m m a n d ) ; } p r o t e c t e d f u n c t i o n d i s p a t c h ( $ c o m m a n d ) { . . . } }
15. CQRS TIPS It's not a magic bullet Apps can contain both CQRS & CRUD Avoid "Anemic domain" ALSO SEE Domain-Driven Design Domain Events Event Sourcing
16. INTERESTED? ( ) Greg Young PDF CQRS - Martin Fowler LiteCQRS for PHP
17. ??? Any questions...
18. THANKS FOR LISTENING Now it's time for a drink! / Special thanks to: / Warnar Boekkooi @boekkooi Ross Tuck @rosstuck