A journey through the Rails request cycle. It might be a bit hard to follow w/o the talk to go along with it. From January 2007

1. a myftical journey
through the
Request Cycle
of
RUBY ON RAILS.
AN
ORATION
IN
TWO PARTS
L.C.
BY

2. PART
ZERO

3. ocol adap
prot ter
dispatcher
controller
view

4. principle
info passed via arguments
via objects
return value ignored

5. protocol
adapter
dispatcher
controller
view

7. principle

8. PART
ONE

9. The Dispatcher:

10. The Dispatcher:
just a class™

11. dispatch(cgi, session_options, output)
Dispatcher

12. fastcgi webrick mongrel
cgi.rb
Dispatcher

13. classic
CGI

14. classic
CGI
supported

15. classic
CGI
supported
Who cares?

16. Finesse arguments.
Find Controller.
Delegate to Controller.
Handle errors.
Tidy up.

17. Finesse arguments.
request response
cgi.rb cgi.rb

18. Find Controller.
ROUTING
populates
request

19. Delegate to Controller.
controller_class.process(request,response)

20. Handle errors.
begin
dispatcher
controller
view
bo
om
!
rescue Exception => exception
end

21. Handle errors.
rescue Exception => exception
controller_class.process_with_exception
(request,response,exception)
end
end

22. Handle errors.
rescue Exception => exception
failsafe_response(output,
'500 Internal Server Error', exception) do
controller_class.process_with_exception
(request,response,exception)
end
end

23. Tidy up.
production
# no-op

24. Tidy up.
production
# no-op
otherwise
framework tidy-up hooks
Dependencies
ActiveRecord

25. response
headers
body

26. PART
TWO

27. Your controller:

28. Your controller:
just an object™

29. process(request,response,method,
*args)
ActionController

30. Setup instance.
Dispatch action.
Render.
Finesse response.
Tidy up.

31. Setup instance.
Set up the magic to make your
actions sing!

32. Setup instance.
Housekeeping

33. Setup instance.
handy accessors
from request: from response:
response
request
params template
cookies session
headers

34. Dispatch action.
instance method
(and, render if you haven't).

35. Dispatch action.
-or-
method missing
(and, render if you haven't).

36. Dispatch action.
-or-
just render.

37. Render.
VIEWY

38. Render.
@assigns =
instance_vars - protected_vars

39. Finesse response.
text/html
Tidy up.
close session

40. Where are

41. Where are
filters?

42. Where are
filters?
mixin!

43. Where are
filters?
mixin!
helpers?

44. Where are
filters?
mixin!
helpers?
mixin!

45. principle
Solid basics
+
Fancy stuff.

46. 5 minute talk subject:
How we choose
your view
for you.

47. json
nothing xml
ml
ht
How we choose
ac
ti
on
your view
rjs
for you.
et
la
mp
la
yo
te
ut
ile
f
text

48. THE
END