[Twisted-web] fragments with child lookup

[Valentino Volonghi aka Dialtone]

On Tue, 26 Sep 2006 21:41:50 +0200, Markus Schiltknecht <markus at bluegap.ch> wrote:
>Thus I think neither Valentino's efforts nor yours are all wasted. And I 
>hope he, you or other nevow hackers still has enough patience to answer my 
>questions.

We always have, although we are a bunch of assholes too. :).

>I'm tempted to write a docFactory which compiles a template from multiple 
>files, instead of using macros. That could automatically include all the 
>'switches' in the template and the designer would not have to hard-wire all 
>children by hand. This would already serve my needs, I guess. Would this 
>still count as 'nevow like' or is it a no-no-no?

This is indeed more nevow-like. When you are in doubt try to work at the 
lowest level possible because the new behavior will be inherited by the upper 
layers (that's why I was suggesting to work at the template layer before).


>from nevow import rend, loaders, tags as T, inevow, static
>
>class BasePage(rend.Page):
>     docFactory = loaders.xmlfile('templates/common.html')
>     title = 'per page title'
>     main_menu = 1
>
>     def render_title(self, ctx, data):
>         ctx.fillSlots('title', self.title)
>         return ctx

ctx.tag.fillSlots(...)
return ctx.tag

>     def render_switch(self, attr):
>         assert(attr is not None)
>         def _(ctx, data):
>             if hasattr(self, attr) and self.__getattribute__(attr):

It's not clear to me what this is for. but in general it's never a good
idea to use special methods directly. In this case you could have done:

getattr(self, attr, default_value)

>                 return ctx

Again: ctx.tag

>             else:
>                 return ()
>         return _
>
>class ContactInfoPage(BasePage):
>     pass
>
>class ContactPage(BasePage):
>     addSlash = True
>     child_info = ContactInfoPage

def child_info(self, ctx):
    return ContactInfoPage()

>class ProductsPage(BasePage):
>     addSlash = True
>     products = True
>
>class EnterPage(BasePage):
>     pass
>
>class RootPage(BasePage):
>     addSlash = True
>     default_background = 1
>     main_menu = 0
>     child_kontakt = ContactPage
>     child_products = ProductsPage
>
>     child_layout = static.File('layout')
>     child_enter = EnterPage()

Same as above, define functions instead.