root/cmfblackbird/trunk/workflow.py

"""
a workflow tool implementation that delegates content integration to adapters for workflow
chain lookup and state storage.

$Id$
"""

import zope.component

from Acquisition import aq_base
from Globals import PersistentMapping
from Products.CMFCore.WorkflowTool import WorkflowTool as BaseTool
from Products.CMFCore.utils import getToolByName

def DefaultWorkflowChain( context, workflow_tool ):
    print "default chain"
    if isinstance( context, basestring ):
        pt = context
    elif hasattr( aq_base( context ), 'getPortalTypeName'):
        pt = ob.getPortalTypeName()
    else:
        pt = None
    if pt is None:
        return ()
    chain = None

    cbt = workflow_tool._chains_by_type
    
    if cbt is not None:
        chain = cbt.get( pt, None )
    if chain is None:
        chain = workflow_tool.getDefaultChainFor( context )
        if chain is None:
            return ()
    return chain

def DefaultWorkflowState( context ):
    if hasattr( aq_base, 'workflow_history'):
        history = ob.workflow_history
    else:
        history = PersistentMapping()
        setattr( ob, 'workflow_history', history )
    return history
    
def DefaultWorkflowStateQuery( context ):
    if hasattr( aq_base( ob ), 'workflow_history'):
        wfh = ob.workflow_history
    else:
        wfh = ()
    return wfh

class WorkflowTool( BaseTool ):

    def getHistoryOf( self, wf_id, ob ):
        """
        Return the history of an object. Invoked by workflow definitions.
        """
        wfh = IWorkflowStateQuery( ob )
        if not wfh:
            return ()
        return wfh.get( wf_id, None )

    def setStatusOf( self, wf_id, ob, status ):
        """
        Append an entry to the workflow history. Invoked by workflow definitions.
        """        
        wfs = IWorkflowState( ob )
        wfh = wfs.get( wf_id, None )
        if wfh is not None:
            wfh = list( wfh )
        else:
            wfh = []
        wfh.append( status )
        wfs[ wf_id ] = tuple( wfh )
            
    def getChainFor( self, ob ):
        """
        Returns the chain that applies to the given object.
        If we get a string as the ob parameter, use it as
        the portal_type.
        """
        return zope.component.queryAdapter( (ob, self), default=() )