[Zope3-dev] local-utility location and registration

[Dominik Huber]

Garanin Michael wrote:

>                                                                          
>Hello!
>My app setup code do follow step:
>1) create simple AppSite (as ISite) in top
>2) create local-utility object, 
>for example PAU = PluggableAuthentication()
>3) AppSite['PAU'] = PAU 
>4) registration the PAU in AppSite/++etc++site/default.
>
>In other words: local-utility object location in top/mysite, but
>registration in top/mysite/++etc++site/default.
>Q: It's work, but is it legal?
>Thanks!
>  
>
IMO it makes sense that the default site folder is invoked if a local 
utility is added to a site.

We use the following helper function for the local utility additon and 
registration:

from zope.app import zapi
from zope.app.container.interfaces import INameChooser
from zope.app.component.interfaces.registration import ActiveStatus
from zope.app.component.interfaces import ISite
from zope.app.utility import UtilityRegistration

def addLocalUtility(site, name, iface, utility, package='default'):
    """Add a utility to a site

    The utility is added to the package and activated.
    This assumes the site has already a Utility Service.
    """
    # preconditions
    if not ISite.providedBy(site):
        raise TypeError('ISite required.')

    # get site manager and site management folder
    sitemanager = site.getSiteManager()
    default = sitemanager[package]

    # add utility to site management folder
    chooser = INameChooser(default)
    folder_name = chooser.chooseName(utility.__name__, utility)
    default[folder_name] = utility

    # create service registration
    path = zapi.getPath(utility)
    registration = UtilityRegistration(name, iface, utility)
    key = default.registrationManager.addRegistration(registration)
    zapi.traverse(default.registrationManager, key).status = ActiveStatus 

    return zapi.traverse(sitemanager, path)

Regards,
Dominik