HTTP2 for the web developer devoxx

Quickie at Devoxx 2015
http://cfp.devoxx.be/2015/talk/AHP-5608/HTTP%2F2_for_the_Web_developer
https://www.youtube.com/watch?v=ssp1ve_A1to

1. @brianclozel #Devoxx HTTP/2 for the web developer Brian Clozel Pivotal Software
2. @brianclozel #Devoxx • Spring Framework committer • https://spring.io lead developer
3. HTTP/2 is about solving latency issues
4. HTTP/2 basics in 6 steps
5. #1 - a single TCP connection
6. #2 - multiple Streams
7. #3 - binary framing
8. Client Server Stream: 3 HEADERS
 GET /java Stream: 5 DATA Stream: 5 HEADERS
 POST /devoxx Stream: 5 DATA Stream: 3 HEADERS Stream: 3 DATA Stream: 5 HEADERS Stream: 3 DATA
9. #4 - Flow Control
10. #5 - HPACK
11. #6 - TLS (not) required
12. Congratulations! https://github.com/bclozel/http2-experiments
13. How should we adapt? • What about « front-end optimizations »? • undo concatenation • keep gzipping content • use ETags, Cache-Control directives • use JS module loaders
14. HTTP/2 new,
 optional features?
15. HTTP/2 Server Push!
16. Client Server Stream: 3 HEADERS
 GET /index.html Stream: 8 RST_STREAM CANCEL Stream: 10 RST_STREAM CANCEL Stream: 3 PUSH_PROMISE Promised Stream: 8
 GET /main.css Stream: 8 HEADERS Stream: 3 PUSH_PROMISE Promised Stream: 10
 GET /script.js
17. Why not send the
 main response first?
18. « The server SHOULD send PUSH_PROMISE (Section 6.6) frames prior to sending any frames that reference the promised responses. This avoids a race where clients issue requests prior to receiving any PUSH_PROMISE frames. »
19. Client Server Stream: 3 HEADERS
 GET /index.html Stream: 3 PUSH_PROMISE Promised Stream: 8
 GET /main.css Stream: 3 HEADERS Stream: 3 DATA Stream: 5 HEADERS
 GET /main.css [Parsing HTML…] !!!
20. Who knows best, then? • Server-side application • HTML structure • number/size of resources • HTTP client • heuristics • state of cache • CPU, battery, local network • Us, developers?
21. HTTP/2
 Stream prioritization
22. Declaring Stream dependencies Stream: 8 HEADERS Dependency: 5 Weight: 55
 GET /image.png
23. Performance: use your
 browser developer tools
25. Implementation checklist • IO & programming model? • serious TLS support? • Server Push support? • Stream prioritization support? • Bonus: reactive streams friendly?
26. @brianclozel #Devoxx Thanks!