Real-Time with Flowdock

Transcript

1. Real-Time with Thursday, March 15, 12
2. @lautis Thursday, March 15, 12
3. “There’s no time like real-time” Thursday, March 15, 12
4. Demo Thursday, March 15, 12
5. Stream changes from backend And send messages Thursday, March 15, 12
6. Thursday, March 15, 12
7. Long-polling XHR-streaming HTMLFile WebSocket Server-Sent Events JSONP streaming XHR multipart Thursday, March 15, 12
8. 3 implementations with 7 transports Thursday, March 15, 12
9. Long-polling Thursday, March 15, 12
10. Long-polling HTTP/1.1 200 OK Content-Type: application/json; Thursday, March 15, 12
11. Long-polling HTTP/1.1 200 OK Content-Type: application/json; [{'content': 'json'}] Thursday, March 15, 12
12. XHR-streaming Thursday, March 15, 12
13. XHR-streaming HTTP/1.1 200 OK Thursday, March 15, 12
14. XHR-streaming HTTP/1.1 200 OK {'content': 'json'} Thursday, March 15, 12
15. XHR-streaming HTTP/1.1 200 OK {'content': 'json'} {'content': 'json'} Thursday, March 15, 12
16. XHR-streaming HTTP/1.1 200 OK {'content': 'json'} {'content': 'json'} {'content': 'json'} Thursday, March 15, 12
17. Server-Sent Events Thursday, March 15, 12
18. Server-Sent Events HTTP/1.1 200 OK Content-Type: text/event-stream Thursday, March 15, 12
19. Server-Sent Events HTTP/1.1 200 OK Content-Type: text/event-stream data: {'content': 'json'} Thursday, March 15, 12
20. Server-Sent Events HTTP/1.1 200 OK Content-Type: text/event-stream data: {'content': 'json'} id: 2 data: {'content': 'json'} Thursday, March 15, 12
21. Server-Sent Events HTTP/1.1 200 OK Content-Type: text/event-stream data: {'content': 'json'} id: 2 data: {'content': 'json'} Sent to server on reconnect Thursday, March 15, 12
22. In JavaScript var es = new EventSource('/events'); es.onmessage = function (e) { console.log(JSON.parse(e.data)); }; Thursday, March 15, 12
23. Built-in in modern browsers Thursday, March 15, 12
24. No IE Thursday, March 15, 12
25. No Android Thursday, March 15, 12
26. Use shim instead https://github.com/Yaffle/EventSource Thursday, March 15, 12
27. Streams are unidirectional Thursday, March 15, 12
28. Sockets are bidirectional Thursday, March 15, 12
29. WebSockets var socket = new WebSocket('/socket'); socket.onmessage = function (e) { console.log(JSON.parse(e.data)); }; Thursday, March 15, 12
30. WebSockets var socket = new WebSocket('/socket'); socket.onmessage = function (e) { console.log(JSON.parse(e.data)); }; socket.onopen = function() { var m = {'content': 'json'}; socket.send(JSON.stringify(m)); } Thursday, March 15, 12
31. Caveats Thursday, March 15, 12
32. Caveats •Limited browser support Thursday, March 15, 12
33. Caveats •Limited browser support •Proxy problems Thursday, March 15, 12
34. Caveats •Limited browser support •Proxy problems •Safari crashes when used with Proxy Auto-Configuration Thursday, March 15, 12
35. Socket.IO “It's care-free realtime 100% in JavaScript.” Thursday, March 15, 12
36. Bugs Thursday, March 15, 12
37. •Reconnection race-conditions Bugs Thursday, March 15, 12
38. •Reconnection race-conditions •Infinite loops with XHR-polling Bugs Thursday, March 15, 12
39. •Reconnection race-conditions •Infinite loops with XHR-polling •DOM Exception 11 Bugs Thursday, March 15, 12
40. Socket.IO “It's care-free realtime 100% in JavaScript.” care-free Thursday, March 15, 12
41. Socket.IO “It's care-free realtime 100% in JavaScript.” Thursday, March 15, 12
42. Why bother? Thursday, March 15, 12
43. Science! It Works, Bitches. Thursday, March 15, 12
44. Latency matters Thursday, March 15, 12
45. Round-trip latency Thursday, March 15, 12
46. Round-trip latency Ping XHR-streaming WebSocket 0 75 150 225 300 Thursday, March 15, 12
47. Round-trip latency Ping XHR-streaming WebSocket 0 75 150 225 300 Thursday, March 15, 12
48. Round-trip latency Ping XHR-streaming WebSocket 0 75 150 225 300 Thursday, March 15, 12
49. Round-trip latency Ping XHR-streaming WebSocket 0 75 150 225 300 Thursday, March 15, 12
50. Real-world metrics from Flowdock Thursday, March 15, 12
51. 96% use WebSockets Thursday, March 15, 12
52. 96% use WebSockets No Flash fallback Thursday, March 15, 12
53. 3% have obsolete browsers Thursday, March 15, 12
54. 1% have network issues Thursday, March 15, 12
55. 1% have network issues (or have disabled WebSockets) Thursday, March 15, 12
56. Network still sucks Thursday, March 15, 12
57. Render optimistically Thursday, March 15, 12
58. Basic operations in Flowdock Thursday, March 15, 12
59. 1.Post new stuff Basic operations in Flowdock Thursday, March 15, 12
60. 1.Post new stuff 2.Receive new stuff Basic operations in Flowdock Thursday, March 15, 12
61. 1.Post new stuff 2.Receive new stuff 3.Modify existing stuff Basic operations in Flowdock Thursday, March 15, 12
62. Posting messages Thursday, March 15, 12
63. •Clients process messages as much as possible Posting messages Thursday, March 15, 12
64. •Clients process messages as much as possible •Server adds unique ID and timestamp to data Posting messages Thursday, March 15, 12
65. •Clients process messages as much as possible •Server adds unique ID and timestamp to data •Message echoed to client Posting messages Thursday, March 15, 12
66. SUP LOL Order sync Thursday, March 15, 12
67. SUP LOL FOO Order sync Thursday, March 15, 12
68. SUP LOL FOO BAR Order sync Thursday, March 15, 12
69. SUP LOL FOO BAR Order sync Thursday, March 15, 12
70. SUP LOL FOO BAR FOO Order sync Thursday, March 15, 12
71. SUP LOL FOO BAR FOO Order sync Thursday, March 15, 12
72. Modifying stuff •Add/remove tag to message •Mark message as deleted Thursday, March 15, 12
73. "Operation, which can be applied multiple times without changing the result beyond the initial application." Idempotent changes Thursday, March 15, 12
74. Error handling is tricky Thursday, March 15, 12
75. Protips •Socket.IO will bite you •SSE is safe choice for streaming •Design for broken internet Thursday, March 15, 12
76. Thanks! Thursday, March 15, 12