Seaside is a web application framework that is written in Smalltalk. Smalltalk has been hugely influential on the development of computer languages but realistically how many people have ever used it? Seaside is a practical application of Smalltalk to the web sphere.

1. The Revenge of Smalltalk
London Geek Nights
July 6, 2009

6. Lukas Renggli
Academics
PhD Student, University of Bern
Open-Source
Core-developer of Seaside
Author of Magritte and Pier
Industry
Independent Software Consultant

7. Agenda
Flow Continuations
Components Objects
Security Closures
Applications Debugger

8. Natural Flow
Source: stock.xchng, Asif Akbar

12. <form action="second.html">
<input type="text" name="value1">
<input type="submit" value="OK">
</form>

13. <form action="second.html">
<input type="text" name="value1">
<input type="submit" value="OK">
</form>
<form action="result.html">
<input type="text" name="value2">
<input type="submit" value="OK">
</form>

14. <form action="second.html">
<input type="text" name="value1">
<input type="submit" value="OK">
</form>
<form action="result.html">
<input type="text" name="value2">
<input type="submit" value="OK">
</form>
<p>
<% value1 + value2 %>
</p>

15. <form action="second.html">
<input type="text" name="value1">
<input type="submit" value="OK">
</form>
<form action="result.html">
<input type="text" name="value2">
<input type="submit" value="OK">
</form>
<p>
<% value1 + value2 %>
</p>

16. <form action="second.html">
<input type="text" name="value1">
<input type="submit" value="OK">
</form>
<form action="result.html">
<input type="text" name="value2">
<input type="submit" value="OK">
</form>
<p>
<% value1 + value2 %>
</p>

17. <form action="second.html">
<input type="text" name="value1">
<input type="submit" value="OK">
</form>
<form action="result.html">
<input type="text" name="value2">
<input type="submit" value="OK">
</form>
<p>
<% value1 + value2 %>
</p>

18. <form action="second.html">
<input type="text" name="value1">
<input type="submit" value="OK">
</form>
<form action="result.html">
<input type="hidden" name="value1" value="<% value1 %>">
<input type="text" name="value2">
<input type="submit" value="OK">
</form>
<p>
<% value1 + value2 %>
</p>

19. <form action="second.html">
<input type="text" name="value1">
<input type="submit" value="OK">
</form>
<form action="result.html">
<input type="hidden" name="value1" value="<% value1 %>">
<input type="text" name="value2">
<input type="submit" value="OK">
</form>
<p>
<% value1 + value2 %>
</p>

20. is different

21. 3 user interactions

22. 3 lines of code

23. value1 := self request: ‘First Number’.

24. value1 := self request: ‘First Number’.
value2 := self request: ‘Second Number’.

25. value1 := self request: ‘First Number’.
value2 := self request: ‘Second Number’.
self inform: value1 + value2.

26. D SL
value1 := self request: ‘First Number’.
I t’sa
value2 := self request: ‘Second Number’.
self inform: value1 + value2.

27. It’s j u st
value1 := self request: ‘First Number’.
S m a l lt a l k
value2 := self request: ‘Second Number’.
self inform: value1 + value2.

28. No request parsing

29. No string fiddling

30. No state machines

31. Demo

32. Reusable
Components
Source: stock.xchng, Lynne Lancaster

35. Reuseable

36. Persistent

37. Model
View Controller
Model, View, Controller

38. Valid
Source: stock.xchng, Al Nakib

39. CSS
Designer

40. XHTML
Developer & Seaside

41. DRY

42. DRY
It ’s a D S L

43. It’s j u st
DRY
S m a l lt a l k

44. Demo

45. 3
Source: stock.xchng, Colin Brough
Default
Secure by

46. Cross Site Scripting
Source: stock.xchng, Afonso Lima

47. Output is encoded
by default

48. Replay Attacks
Source: stock.xchng, Afonso Lima

49. Session
_s=Ru8ZKgqjy0uDX3kf
96-bit

50. Page
_k=K5EQyqKE
48-bit

51. Parameter Tampering
Source: stock.xchng, Afonso Lima

52. Names are generated
automatically

53. Names are bound
to functions

54. No manual
request parsing

55. html submitButton
callback: [ self inform: ‘Hey’ ];
with: ‘Click Here’

56. html submitButton
a D S L
It ’s
callback: [ self inform: ‘Hey’ ];
with: ‘Click Here’

57. It’s j u st
html submitButton
S m a l lt a l k
callback: [ self inform: ‘Hey’ ];
with: ‘Click Here’

58. Web 2.0
Source: Flickr, Benjamin Jackson

59. Source: Flickr, psrman's

60. Comet
Source: Flickr, psrman's

61. a D S L
It ’s

62. It’s j u st
S m a l lt a l k

63. Demo

64. 5 Applications
Source: stock.xchng, Steve Woods

65. In productive use
since 2002

70. Seaside

71. MIT License

73. External Interface Support
XML Support enables XML–Smalltalk object
Platform
256MB RAM, 400MB disk
mapping, includes a server interface via XML
0MHz PC, 128MB RAM, 400MB disk request handlers and reading of remote resources
station or server, 64MB RAM, 200MB disk via TCP sockets using HTTP requests
m/6000, POWERStation OLE Support enables an application to use OLE
erver, 128MB RAM, 400MB disk clients and custom control services.
1a Library Manager Domino Connection allows an application to
4.2 or 5.1 retrieve and work with Domino documents as well
p 4.0 + FP11 as access Notes mail system.
p Server for e-Business
ME - EMADMIN only
2000, 2000 Server,
d Server
XP Professional
Server 2003 Download a risk-free trial copy:
Vista Business, Enterprise, www.instantiations.com/VAST/download
te
is Version 8 or 9
rsion 11.0 or 11i
on 5.1, 5.2 or 5.3
inux 9 and Advance Server 2.1
erprise 10
visit www.instantiations.com/VAST
Build Quality Software
WindowBuilder are trademarks of Instantiations. All other trademarks mentioned are the property of their respective owners.

74. www.seaside.st

75. www.seaside.st

76. www.swa.hpi.uni-potsdam.de/seaside/tutorial/

77. book.seaside.st

78. www.seaside.st
www.lukas-renggli.ch