![WOComponent
subclass: #BillingAddress
instanceVariableNames: ‘ship bill’
processRequest: aRequest
bill := self addressFrom: aRequest.
^ next value: bill
“BillingAddress new next:
[:bill |
PaymentInfo new
billingAddress: bill;
....]”](https://image.slidesharecdn.com/esug2004-seaside-101024113117-phpapp02/85/Winning-the-Application-Server-Arms-Race-28-320.jpg)
![checkoutProcess
^ ShippingAddress new next:
[:ship |
BillingAddress new next:
[:bill |
PaymentInfo new next:
[:pay |
ConfirmationPage new
shippingAddress: ship;
billingAddress: bill;
paymentInfo: pay;
yourself]](https://image.slidesharecdn.com/esug2004-seaside-101024113117-phpapp02/85/Winning-the-Application-Server-Arms-Race-29-320.jpg)
![checkoutProcess
^ PaymentInfo new next:
[:pay |
ShippingAdress new next:
[:ship |
BillingAddress new next:
[:bill |
ConfirmationPage new
shippingAddress: ship;
billingAddress: bill;
paymentInfo: pay;
yourself]](https://image.slidesharecdn.com/esug2004-seaside-101024113117-phpapp02/85/Winning-the-Application-Server-Arms-Race-30-320.jpg)
![renderOn: html
html form: [
html label: ‘Name’.
html textInputNamed: ‘name’; break.
html label: ‘Street’.
html textInputNamed: ‘street’; break.
html label: ‘City’.
html textInputNamed: ‘city’; break.
html label: ‘Country’.
html selectNamed: ‘country’ do: [
html optionNamed: ‘CA’ label: ‘Canada’.
html optionNamed: ‘US’ label: ‘US’.
]; break.
html submitButton.
]
processRequest: aRequest
name := aRequest at: ‘name’.
street := aRequest at: ‘street’.
...](https://image.slidesharecdn.com/esug2004-seaside-101024113117-phpapp02/85/Winning-the-Application-Server-Arms-Race-35-320.jpg)
![renderOn: html
html form: [
html label: ‘Name’.
html textInputWithCallback: [:v | name := v]; break.
html label: ‘Street’.
html textInputWithCallback: [:v | street := v]; break.
html label: ‘City’.
html textInputWithCallback: [:v | city := v]; ‘city’; break.
html label: ‘Country’.
html selectFromList: self countries; break.
html submitButtonWithAction: [self saveAddress].
]](https://image.slidesharecdn.com/esug2004-seaside-101024113117-phpapp02/85/Winning-the-Application-Server-Arms-Race-36-320.jpg)
![<form>
Name: <input name="1"><br>
Street: <input name="2"><br>
City: <input name="3"><br>
Country:
<select name="4">
<option value="5">Canada</option>
<option value="6">US</option>
</select>
<br>
<input type="submit" name="7" value="Submit">
</form>
aRequest(
‘1’->‘Avi’,
‘2’->...,
‘7’-> ‘Submit’)
aCallbackStore(
‘1’->[:v | name := v],
‘2’->...,
‘7’->[self saveAddress])](https://image.slidesharecdn.com/esug2004-seaside-101024113117-phpapp02/85/Winning-the-Application-Server-Arms-Race-37-320.jpg)
Winning the Application Server Arms Race
- 1. Winning the Application Server Arms Race Using Smalltalk to Redefine Web Development Avi Bryant
- 2. Web apps: why bother? “I’m more of the mind that HTML based apps suck.” — James Robertson
- 3. Web apps: why bother? “One of the reasons to use Lisp in writing Web-based applications is that you ca! use Lisp. When you’re writing software that is only going to run on your own servers, you can use whatever language you want.” — Paul Graham
- 4. What is a web app? “A collection of functions that take HTTP requests as input and produce HTTP responses as output.”
- 5. What is a web app? User with Web Browser GET /foo?x=3 ... Content-Type: text/html ... /foo
- 6. What is a web app? User with Web Browser GET /foo?x=3 ... Content-Type: text/html <a href=“/bar” ... /foo /bar /baz
- 9. Get Shipping Address Get Billing Address Get Payment Info Show Confirmation Cart info Cart info Shipping info Cart info Shipping info Billing info Cart info Shipping info Billing info Payment info
- 10. /shipping User with Web Browser cart /billing cart shipping cart shipping /payment cart shipping billing cart shipping billing cart shipping billing payment
- 11. User with Web Browser cart cart shipping cart shipping cart shipping billing cart shipping billing cart shipping billing payment formatting processing formatting do stuff processing formatting do stuffdo stuff processing
- 12. an App a32cf6d a Sessiona Sessiona Session 76ebc65 ... User GET /foo?sid=a32cf6d ... <a href=“/bar?sid=a32cf6d”>... /foo
- 13. an App a32cf6d a Sessiona Sessiona Session 76ebc65 ... User GET /bar?sid=a32cf6d ... <a href=“/baz?sid=a32cf6d”>... /bar
- 14. /shipping User with Web Browser /billing sid shipping /payment sid billing sid payment a Session shipping billing sid sid sid sessions
- 15. Book flight Browse flights Choose flight Choose seat Why global session state is evil
- 16. Book flight Browse flights Choose flight Choose seat Choose flight Choose seat Why global session state is evil
- 17. Book flight Browse flights Choose flight Choose seat Choose flight Choose seat ? Why global session state is evil
- 18. an App a32cf6d a Sessiona Sessiona Session 76ebc65 ... a Component f5c a Component a Component a21 ...
- 19. ... <input name=“page” value=“f5b”>... a Session a21 a BrowseFlights POST ... page=a21&flight=747 ... <input name=“page” value=“a21”>... User a ChooseFlight f5b
- 20. a Session a21 a BrowseFlights POST ... page=a21&flight=525 User ... <input name=“page” value=“cc4”>... a ChooseFlight cc4 f5b a ChooseFlight
- 21. WOComponent subclass: #BillingAddress instanceVariableNames: ‘ship bill’ response ^ ‘<form ...’ processRequest: aRequest bill := self addressFrom: aRequest. ^ PaymentInfo new shippingAddress: ship; billingAddress: bill; yourself
- 22. “Seaside is to most other Smalltalk web toolkits as Smalltalk is to most other OO languages, it’s as simple as that.” — Cees de Groot
- 24. WOComponent subclass: #BillingAddress instanceVariableNames: ‘ship bill’ processRequest: aRequest bill := self addressFrom: aRequest. ^ PaymentInfo new shippingAddress: ship; billingAddress: bill; yourself
- 25. WOComponent subclass: #BillingAddress instanceVariableNames: ‘ship bill’ processRequest: aRequest bill := self addressFrom: aRequest. ^ PaymentInfo new shippingAddress: ship; billingAddress: bill; next: (ConfirmationPage new) yourself
- 26. WOComponent subclass: #BillingAddress instanceVariableNames: ‘ship bill’ processRequest: aRequest bill := self addressFrom: aRequest. ^ next shippingAddress: ship; billingAddress: bill; yourself
- 27. checkoutProcess ^ (ShippingAddress new next: (BillingAddress new next: (PaymentInfo new next: (ConfirmationPage new))))
- 28. WOComponent subclass: #BillingAddress instanceVariableNames: ‘ship bill’ processRequest: aRequest bill := self addressFrom: aRequest. ^ next value: bill “BillingAddress new next: [:bill | PaymentInfo new billingAddress: bill; ....]”
- 29. checkoutProcess ^ ShippingAddress new next: [:ship | BillingAddress new next: [:bill | PaymentInfo new next: [:pay | ConfirmationPage new shippingAddress: ship; billingAddress: bill; paymentInfo: pay; yourself]
- 30. checkoutProcess ^ PaymentInfo new next: [:pay | ShippingAdress new next: [:ship | BillingAddress new next: [:bill | ConfirmationPage new shippingAddress: ship; billingAddress: bill; paymentInfo: pay; yourself]
- 31. “...programming language features do well (all other things being equal) when they eliminate either distant or dynamic state and replace it with either close or lexical state. The underlying point being that we may favour language features that facilitate copying and modifying small bits of code -- fragments which work in their new context -- as a fundamental programming activity.” — Graydon Hoare
- 32. checkoutProcess |pay ship bill| pay := self call: PaymentInfo new. ship := self call: ShippingAddress new. bill := self call: BillingAddress new. self call: (ConfirmationPage new shippingAddress: ship; billingAddress: bill; paymentInfo: pay)
- 33. “We could write the code to say, if the user clicks on this link, go to the color selection page, and then come back here.... It made our software visibly more sophisticated than that of our competitors.” — Paul Graham
- 34. <form> Name: <input name="name"><br> Street: <input name="street"><br> City: <input name="city"><br> Country: <select name="country"> <option value="CA">Canada</option> <option value="US">US</option> </select> <br> <input type="submit"> </form> aRequest( ‘name’->‘Avi’, ‘street’-> ‘123 W. 15th’ ‘city’->‘Vancouver’, ‘country’-> ‘CA’)
- 35. renderOn: html html form: [ html label: ‘Name’. html textInputNamed: ‘name’; break. html label: ‘Street’. html textInputNamed: ‘street’; break. html label: ‘City’. html textInputNamed: ‘city’; break. html label: ‘Country’. html selectNamed: ‘country’ do: [ html optionNamed: ‘CA’ label: ‘Canada’. html optionNamed: ‘US’ label: ‘US’. ]; break. html submitButton. ] processRequest: aRequest name := aRequest at: ‘name’. street := aRequest at: ‘street’. ...
- 36. renderOn: html html form: [ html label: ‘Name’. html textInputWithCallback: [:v | name := v]; break. html label: ‘Street’. html textInputWithCallback: [:v | street := v]; break. html label: ‘City’. html textInputWithCallback: [:v | city := v]; ‘city’; break. html label: ‘Country’. html selectFromList: self countries; break. html submitButtonWithAction: [self saveAddress]. ]
- 37. <form> Name: <input name="1"><br> Street: <input name="2"><br> City: <input name="3"><br> Country: <select name="4"> <option value="5">Canada</option> <option value="6">US</option> </select> <br> <input type="submit" name="7" value="Submit"> </form> aRequest( ‘1’->‘Avi’, ‘2’->..., ‘7’-> ‘Submit’) aCallbackStore( ‘1’->[:v | name := v], ‘2’->..., ‘7’->[self saveAddress])