Hypermedia APIs for the Enterprise

by Jon Moore @ Apistrat NYC (Feb. 2013)

Transcript

1. Hypermedia  APIs  for  the  Enterprise     Jon  Moore  (@jon_moore)   Technical  Fellow,  Chief  Engineer  
2. How  do  you  scale  a  development  team?  
3. How  do  you  scale  a  development  team?  
4. Amdahl’s  Law   hDp://en.wikipedia.org/wiki/File:Amdahl_march_13_2008.jpg  (Pkivolowitz  at  en.wikipedia)    
5. Need  to  operate  independently…  
6. Conway’s  Law   Melvin  E.  Conway,  “How  do  commiDees  invent?”,  Datama%on,  14(4):28—31,  April  1968.  
7. Will  tend  to  build  their  own  widgets…  
8. Loose  coupling   hDp://www.flickr.com/photos/usnaYonalarchives/3695598804/  (public  domain)  
9. Essen@al  Components  of  an  API   DOMAIN MODEL OPERATIONS & WORKFLOW INVOCATION MECHANICS
10. Domain  Models   TVEpisode   TVSeason   TVSeries   part-­‐of-­‐season   part-­‐of-­‐series   part-­‐of-­‐series   “The  Simpsons”   name  
11. Workflow:  Client  Applica@on  State   START   Search   Results   Cart   Item   Detail   Shipping   &   Billing   Payment   ConfirmaYon  
12. Mechanics  for  Transi@ons   POST /api/widgets HTTP/1.1 Host: www.example.com Content-Type: application/json Content-Length: 13 {‘foo’:‘bar’} method   URI   formaeng  of  request  body  
13. Evolvability:  “Must  Ignore”   hDp://www.flickr.com/photos/johnsnape/4258191545/  by  John  Snape  (CC  BY  2.0)  
14. Evolving  Models   TVEpisode   TVSeason   TVSeries   part-­‐of-­‐season   part-­‐of-­‐series   part-­‐of-­‐series   “The  Simpsons”   name   Video   associated-­‐media  
15. Evolving  Workflow   START   Search   Results   Cart   Item   Detail   Shipping   &   Billing   Payment   ConfirmaYon   update  qty   edit   Gii  Message   submit  
16. What  is  this  mythical  content  type?  
17. HTML5  Microdata  (schema.org)   <div itemscope=“1” itemtype=“http://schema.org/TVSeries”> <span itemprop=“name”>The Simpsons</span> </div>
18. Link  Rela@ons:  IoC  for  Workflow   author next prev first last edit index item search http://example.com/my-rel
19. Links  and  Forms:  Request  Recipes   hDp://www.flickr.com/photos/naYonalarchives/4157825846/  (UK  NaYonal  Archives,  public  domain,  c.  1624)  
20. •  SemanYc  markup   •  RDFa:  hDp://www.w3.org/TR/xhtml-­‐rdfa-­‐primer/   •  JSON-­‐LD:  hDp://json-­‐ld.org/   •  Hypermedia  controls   •  CollecYon+JSON:  hDp://amundsen.com/media-­‐types/collecYon/   •  HAL:  hDp://stateless.co/hal_specificaYon.html   •  Siren:  hDps://github.com/kevinswiber/siren   •  Link  relaYons   •  IANA  registry:          hDp://www.iana.org/assignments/link-­‐relaYons/link-­‐relaYons.xml   •  Link  header:  hDp://tools.ieq.org/html/rfc5988   Related  Work  
21. •  Enterprises  ≈  collecYon  of  ADs   •  Independent  Evolvability  is  the  key  to  scale   –  Domain  model  (“where  am  I?”)   –  Workflow  (“what  can  I  do  next?”)   –  Mechanics  (“how  do  I  do  it?”)   •  HTML5  offers  an  exisYng,  pracYcal  opYon  for   building  hypermedia  APIs   •  Efforts  underway  to  duplicate  this  for  JSON   Conclusions