On 12-09-04 3:24 PM, Frank Shearar wrote:
On 4 September 2012 19:08, Chris Cunnington smalltalktelevision@gmail.com wrote:
On 12-09-04 10:56 AM, H. Hirzel wrote:
Frank,
It it correct to assume that you have released the code of your Altitude application example
Serving JSON at Altitude http://www.lshift.net/blog/2012/07/31/serving-json-at-altitudeunder MIT?
Yes, although I haven't mentioned it anywhere.
--Hannes
This is cool. I think it addresses my question of how do you get data from the model to the view. I should be looking at #withLocator:. I needed to change a few things to make it work for me.
http://ss3.gemstone.com/ss/Oakville/Reflect-Core-chc.1.mcz
I made some notes to help me try to puzzle things together. They are sort of a shed snake skin, but they may be useful.
Chris
- This uses an older version of Altitude, as it has ALLocator. That was
removed for ALAbstractLocator to switch from using subclassing to the Strategy pattern. The ALLocator is likely more comprehensible to me anyway. To use ALLocator regress the install of the package AL-Application back to AL-Application-cwp.17.mcz.
- You don't need, with the newer Altitude, to add #initializeHandler in the
ALApplication subclass. As a default it was moved up to ALApplication.
- I'm guessing in ParamLocator>>resourceForPath: that this:
caseOf: { ['senders-of'] -> [(SendersOf reflecting: aPath second asSymbol) asResource]. otherwise: [ALNotFound signal: aPath printString].
might actually be this:
caseOf: { ['senders-of'] -> [(SendersOf reflecting: aPath second asSymbol) asResource]} otherwise: [ALNotFound signal: aPath printString].
The period at the end of the #asResource block is stepping on the #caseOf:otherwise: selector. And a subsequent second $} is missing.
The SendersOf class definition needs an instvar #selector
Temporary variable not required in Workspace.
The destination URL is http://localhost:9090/implementors-of/today but in
ParamLocator>>resourceForPath: we have 'senders-of' so perhaps the URL should be http://localhost:9090/senders-of/today.
- ParamLocator>>resourceForPath invokes ALPath>>second, which does not
exist. Added one:
ALPath>>second ^ self at: 2
- #setName in SendersOf>>renderOn: suggests an instvar, but replace it with
the string 'senders-of', which seems to do the trick.
I'm glad someone took the trouble to look so closely at the code, and a bit embarrassed at all the problems. The reason for the problems is simple: the code's hacked out of a fledgling project, and clearly I didn't pay close enough attention to ensure the bits made sense ripped out of their context. (SendersOf and its sibling Implementors of are subclasses of something else that introduces the selector instvar.
frank
I'm pleased you're not offended by my picayune observations. This is quite a useful demo for me to better understand Altitude and the Strategy pattern. I can see now that people are supposed to write locator classes as subclasses of ALAbstractLocator as needed, which is what the blog post shows. Once I saw what was supposed to happen it was simple to change it to work with the latest version of Altitude. Great blog post.
Thanks, Chris