[PEAK] Does a PEAK-ized webware esist ?

[Wayne Larsen]

Ian Bicking wrote:
> wayne at larsen.st wrote:
>>
>> So, backing up, what would I see as the perfect framework:
>>  - Webware style app server, with the mod_webkit adapter, so that the app
>> server can be run behind Apache for dynamic content
>>  - Utilize the PEAK config and component frameworks for allowing flexible
>> configuration of servlets.  Servlets in a directory tree should allow for
>> dynamic discovery and configuration, so that subdirectories can override
>> settings as required.
> 
> 
> There's something along these lines in Standalone WebKit (which is where 
> any of this development would make sense).  URLParser picks up 
> configuration files named "webware.ini", and adds them to a 
> request-specific configuration.  Since you can reroute URL parsing in 
> several ways, you can do something like:
> 
> /MyRoot/webware.ini
> /MyRoot/__init__.py which points to -->
> /AppRoot/...
> 
> Then servlets in AppRoot can see the configuration from 
> /MyRoot/webware.ini, but you don't need to touch the application's files 
> or directory at all.  You can do stuff in __init__.py so that everything 
> is redirected to another directory (after reading the config) without 
> consuming any of the URL.  You should be able to do this redirection in 
> webware.ini, but you can't now -- URL controlling configurations can't 
> be passed along (since they only apply to one location), so there has to 
> be some mechanism either for URLParser to consume configuration, or ways 
> to mark configurations as local, URL-specific, or something.
> 
> I don't think that's all of what you want, but it probably fits in there 
> somewhere.  Potentially URLParser could look for other .ini files to 
> bring into the request.
> 
That is what I was looking at -- I was trying to understand how peak.web 
   maps from a url to an actual resource, since I have a feeling the 
solution I'm looking for is some combination of the two.


> I'm open to suggestions about how Standalone WebKit does configuration. 
>  Maybe PEAK configuration would fit.  This stuff is in 
> Sandbox.ianbicking.WebKit.Configuration (in webware-sandbox.sf.net).
> 
> Some of the details of WebKit.Configuration, which might align with 
> PEAK's configuration, or not:
> 
> * I allow for the possibility of other configuration formats besides 
> .ini, but haven't implemented any other parsers.
> * When option values are retrieved, type information is given.  So 
> there's no configuration schema.
> * While several configuration files are brought in, they all get loaded 
> into the same space (except for configuration files URLParser adds). The 
> only partitioning is the section headers in the .ini files themselves.  
> This includes configuration files URLParser brings in.
> * Configuration.ChainedConfiguration allows you to look through 
> different configurations in order.  This way URLParser's configuration 
> shadows the global configuration.
> * There's a separate URLParser.FileParser instance for each segment of 
> the path, and each instance has its own configuration (or none if 
> there's no webware.ini).  Other kinds of parsers could add configuration 
> differently.  Or the parser could add a configuration when it finds the 
> servlet, i.e., look for servletname.ini and load that configuration.
> 
> I don't really know enough about PEAK configuration to comment on the 
> rest much...
> 
One would think that configuration is a solved problem :)  I'm not sure 
the best way to reconcile the two - I also have a tendency to throw away 
working code that I should be fighting - but it seems simpler to me to 
just use peak's configuration system rather than supporting both.

>> This last step is where I'm at right now - I would like to enable a
>> structure like:
>>
>> ServletRoot/main.ini
>> ServletRoot/Site1/
>> ServletRoot/Site1/site.ini
>> ServletRoot/Site1/index.py
>> ServletRoot/Site1/page1.py
>> ServletRoot/Site1/subdir/resource.ini
>> ServletRoot/Site1/subdir/page2.py
>> ServletRoot/Site2/
>> ServletRoot/Site2/site.ini
>> ServletRoot/Site2/index.py
>> ...
> 
> 
> What's the meaning of main.ini, site.ini, and resource.ini?  I.e., what 
> distinguishes them, when do they get loaded, what's their scope?  Is 
> this a PEAK convention?
> 
I was just trying to distinguish between several layers of configuration 
-- site.ini would be the main configuration for a website, but it may be 
possible to consolidate some configuration "ie main.ini", or override it 
(ie resource.ini, which has nothing to do with peak.web's resources.ini).