Age of the Micro Service - CodeSlice Aug 2014

Presentation on Micro Services given at CodeSlice Aug 2014 hosted at the Kainos Software offices in Belfast

Transcript

1. #codeslice   Re-­‐inven.ng  Java  as  a  lightweight  boxer   Age  of  the     Micro  Service  
2. About  Me   Chris  Cundill     Java  &  Scala  dev  with  team  lead   experience.    Worked  on  exci.ng  high-­‐scale   projects  with  Interna.onal  Baccalaureate,   Friends  Life  Insurance  and  Money   Supermarket.     Recently  maintained  popular   #ThisWeekInScala  community  blog  for   over  a  year.  
3. Contents   •  Theory:  Micro  services   •  New  age  Java   •  Dropwizard   •  Exercise  with  Dropwizard  
4. Micro  services:  The  Antonym  
5. Micro  services:  The  Synonym  
6. Theory:  Micro  services     Mar.n  Fowler   “…  a  par.cular  way  of  designing   soSware  applica.ons  as  suites  of   independently  deployable  services”     A  Microservice  is  a  discrete,  isolated,  and   named  piece  of  logic  that  consumes  0…N  inputs   and  produces  0…N  outputs  and  which  is   executed  for  the  benefit  of  an  invoker—it  is   performed  as  a  service.   Victor  Klang   hZp://mar.nfowler.com/ar.cles/microservices.html   hZp://klangism.tumblr.com/post/80087171446/microservices  
7. Theory:  Micro  services    
8. Theory:  Microservices   •  Architectural  Style   –  Building  apps  as  suite  of  services   –  Componen.za.on  via  Services   •  Klang  says  Microservices  are:   –  Discrete   •  Small  number  of  responsibili.es   –  Isolated   •  Provisioned  separately   –  Named   •  Unique  signature/iden.fier   –  Defined   •  Input  and  output  defined  and  documented  
9. Theory:  Microservices   •  Pros   –  Maintain  small  chunks   –  Scale  separately   –  Re-­‐usable  services   –  Technology  freedom   •  Best  tech  for  the  job   •  Cons   –  More  provisioning  for  Ops!   –  Distributed  System  Complexity   –  Increased  network  latency  
10. Theory:  Microservices   •  RESTful   – All  the  methods  you  need…   •  GET,  POST,  PUT,  DELETE   – All  the  status  codes  you  need…   •  200,  201,  400,  401,  402,  404,  500   – …and  don’t  need   •  418  I'm  a  teapot   –  hZp://en.wikipedia.org/wiki/Representa.onal_state_transfer   –  hZp://hZpstatus.es/  
11. Money  Supermarket  Microservices   agg-­‐api   web-­‐api   Mongo   Redis  
12. DVLA  Microservices   driver-­‐enquiry-­‐server   driver-­‐filter-­‐server   drivers  db  
13. hZp://microservices.io  
14. “organiza.ons  which   design  systems  ...  are   constrained  to  produce   designs  which  are  copies   of  the  communica.on   structures  of  these   organiza.ons”   hZp://en.wikipedia.org/wiki/Conway's_law   -­‐  Melvin  Conway  
15. Micro  services  on  the  JVM   Heavyweight   Lightweight   Vs  
16. Dropwizard   •  Stable,  mature  libraries  from  the  Java   ecosystem   •  Simple,  light-­‐weight  package   •  Produc.on-­‐ready   – sophis.cated  configura.on,  applica.on  metrics,   health  checks,  logging  (with  archiving),   opera.onal  tools  &  more    
17. “Programming  is   the  art  of  telling   another  human   what  one  wants  the   computer  to  do.”   hZp://en.wikipedia.org/wiki/The_Art_of_Computer_Programming   -­‐  Donald  Knuth    
18. Hands  on  exercise   •  Hello  hackers!   •  15  mins   •  Build  from  scratch!   •  github.com/cpcundill/dvla-­‐hackathon-­‐ex1