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はじめに

This document tells how to access view and context utilities in Plone.

IPortalState and IContextState

IPortalState define IContextState view-like interfaces to access miscencancellous information useful for the current page render. The views are cached properly, so they should access the information quite effective manner

• IPortalState is mapped as @@plone_portal_state view for traversing.
• IContextState is mapped as @@plone_context_state view for traversing.

To see what’s available through the interface, read documentation in plone.app.layout.globals.interfaces module.

Example how to get the current language:

from Acquisition import aq_inner
from zope.component import getMultiAdapter

context = aq_inner(self.context)
portal_state = getMultiAdapter((context, self.request), name=u'plone_portal_state')

current_language = portal_state.language()

Example how to expose portal_state to template:

ZCML includes allowed_attributes:

<browser:page
    for="*"
    name="test"
    permission="zope2.Public"
    class=".views.MyView"
    allowed_attributes="portal_state"
    />

Python class exposes the variable:

from Acquisition import aq_inner
from zope.component import getMultiAdapter

class MyView(BrowserView):

    @property
    def portal_state(self):
        context = aq_inner(self.context)
        portal_state = getMultiAdapter((context, self.request), name=u'plone_portal_state')
        return portal_state

Template can use it:

<div>
    The language is <span tal:content="view/portal_state/language" />
</div>

You can directly look up portal_state in template using acquisition magic and view traversing, without need of ZCML code or Python view code changes. This is useful e.g. overridden viewlet templates:

<!--

    In traversing @@ marks that the traversing
    machine should look up a view by that name.

    First we look up the view and then use
    it to access the variables defined in
    IPortalState interface.

-->

<div tal:define="portal_state context/@@plone_portal_state" >
    The language is <span tal:content="portal_state/language" />
</div>

Using in templates and expressions

You can use IContextState and IPortalState in TALES expressions, like portal_actions too.

Example portal_actions condition expression:

python:object.restrictedTraverse('@@plone_portal_state').language() == 'fi'

Tools

Tools are persistent utility classes available in the site root. They are visible in ZMI. Tools include things like

• portal_catalog - Search and indexing facilities for content
• portal_workflow - Inquiry and do workflow related actions
• portal_membership - User registration information

ITools interface

plone.app.layout.globals.interfaces.ITools interface and Tools BrowserView provide cached access for most often needed tools.

ITools is mapped as plone_tools view for traversing.

Example:

from Acquisition import aq_inner
from zope.component import getMultiAdapter

context = aq_inner(self.context)
tools = getMultiAdapter((context, self.request), name=u'plone_tools')

portal_url = tools.url()

# The root URL of the site is got by using portal_url.__call__()
# method

the_current_root_url_of_the_site = portal_url()

getToolByName

getToolByName is old-fashioned way of getting tools the context object as a start point. It also works for tools which are not defined in ITools interface.

getToolByName gets any Plone portal root item using acquisition.

Example:

from Products.CMFCore.WorkflowCore import WorkflowException

# Do the workflow transition "submit" for the current context
workflowTool = getToolByName(self.context, "portal_workflow")
workflowTool.doActionFor(self.context, "submit")

getSite

sometimes you don’t have a context and/or you just need to get the portal object (site root):

from zope.app.component.hooks import getSite
portal = getSite()