appypod-rattail/fields/workflow.py

373 lines
17 KiB
Python

# ------------------------------------------------------------------------------
# This file is part of Appy, a framework for building applications in the Python
# language. Copyright (C) 2007 Gaetan Delannay
# Appy is free software; you can redistribute it and/or modify it under the
# terms of the GNU General Public License as published by the Free Software
# Foundation; either version 3 of the License, or (at your option) any later
# version.
# Appy is distributed in the hope that it will be useful, but WITHOUT ANY
# WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
# A PARTICULAR PURPOSE. See the GNU General Public License for more details.
# You should have received a copy of the GNU General Public License along with
# Appy. If not, see <http://www.gnu.org/licenses/>.
# ------------------------------------------------------------------------------
import types, string
from group import Group
from appy.px import Px
from appy.gen.mail import sendNotification
# Default Appy permissions -----------------------------------------------------
r, w, d = ('read', 'write', 'delete')
# ------------------------------------------------------------------------------
class Role:
'''Represents a role, be it local or global.'''
appyRoles = ('Manager', 'Owner', 'Anonymous', 'Authenticated')
appyLocalRoles = ('Owner',)
appyUngrantableRoles = ('Anonymous', 'Authenticated')
def __init__(self, name, local=False, grantable=True):
self.name = name
self.local = local # True if it can be used as local role only.
# It is a standard Zope role or an application-specific one?
self.appy = name in self.appyRoles
if self.appy and (name in self.appyLocalRoles):
self.local = True
self.grantable = grantable
if self.appy and (name in self.appyUngrantableRoles):
self.grantable = False
# An ungrantable role is one that is, like the Anonymous or
# Authenticated roles, automatically attributed to a user.
# ------------------------------------------------------------------------------
class State:
'''Represents a workflow state.'''
def __init__(self, permissions, initial=False, phase=None, show=True):
self.usedRoles = {}
# The following dict ~{s_permissionName:[s_roleName|Role_role]}~
# gives, for every permission managed by a workflow, the list of roles
# for which the permission is granted in this state. Standard
# permissions are 'read', 'write' and 'delete'.
self.permissions = permissions
self.initial = initial
self.phase = phase
self.show = show
# Standardize the way roles are expressed within self.permissions
self.standardizeRoles()
def getName(self, wf):
'''Returns the name for this state in workflow p_wf.'''
for name in dir(wf):
value = getattr(wf, name)
if (value == self): return name
def getRole(self, role):
'''p_role can be the name of a role or a Role instance. If it is the
name of a role, this method returns self.usedRoles[role] if it
exists, or creates a Role instance, puts it in self.usedRoles and
returns it else. If it is a Role instance, the method stores it in
self.usedRoles if it is not in it yet and returns it.'''
if isinstance(role, basestring):
if role in self.usedRoles:
return self.usedRoles[role]
else:
theRole = Role(role)
self.usedRoles[role] = theRole
return theRole
else:
if role.name not in self.usedRoles:
self.usedRoles[role.name] = role
return role
def standardizeRoles(self):
'''This method converts, within self.permissions, every role to a
Role instance. Every used role is stored in self.usedRoles.'''
for permission, roles in self.permissions.items():
if isinstance(roles, basestring) or isinstance(roles, Role):
self.permissions[permission] = [self.getRole(roles)]
elif roles:
rolesList = []
for role in roles:
rolesList.append(self.getRole(role))
self.permissions[permission] = rolesList
def getUsedRoles(self): return self.usedRoles.values()
# ------------------------------------------------------------------------------
class Transition:
'''Represents a workflow transition.'''
def __init__(self, states, condition=True, action=None, notify=None,
show=True, confirm=False, group=None):
self.states = states # In its simpler form, it is a tuple with 2
# states: (fromState, toState). But it can also be a tuple of several
# (fromState, toState) sub-tuples. This way, you may define only 1
# transition at several places in the state-transition diagram. It may
# be useful for "undo" transitions, for example.
self.condition = condition
if isinstance(condition, basestring):
# The condition specifies the name of a role.
self.condition = Role(condition)
self.action = action
self.notify = notify # If not None, it is a method telling who must be
# notified by email after the transition has been executed.
self.show = show # If False, the end user will not be able to trigger
# the transition. It will only be possible by code.
self.confirm = confirm # If True, a confirm popup will show up.
self.group = Group.get(group)
def getName(self, wf):
'''Returns the name for this state in workflow p_wf.'''
for name in dir(wf):
value = getattr(wf, name)
if (value == self): return name
def getUsedRoles(self):
'''self.condition can specify a role.'''
res = []
if isinstance(self.condition, Role):
res.append(self.condition)
return res
def isSingle(self):
'''If this transition is only defined between 2 states, returns True.
Else, returns False.'''
return isinstance(self.states[0], State)
def isShowable(self, workflow, obj):
'''Is this transition showable?'''
if callable(self.show):
return self.show(workflow, obj.appy())
else:
return self.show
def hasState(self, state, isFrom):
'''If p_isFrom is True, this method returns True if p_state is a
starting state for p_self. If p_isFrom is False, this method returns
True if p_state is an ending state for p_self.'''
stateIndex = 1
if isFrom:
stateIndex = 0
if self.isSingle():
res = state == self.states[stateIndex]
else:
res = False
for states in self.states:
if states[stateIndex] == state:
res = True
break
return res
def isTriggerable(self, obj, wf, noSecurity=False):
'''Can this transition be triggered on p_obj?'''
wf = wf.__instance__ # We need the prototypical instance here.
# Checks that the current state of the object is a start state for this
# transition.
objState = obj.State(name=False)
if self.isSingle():
if objState != self.states[0]: return False
else:
startFound = False
for startState, stopState in self.states:
if startState == objState:
startFound = True
break
if not startFound: return False
# Check that the condition is met, excepted if noSecurity is True.
if noSecurity: return True
user = obj.getTool().getUser()
if isinstance(self.condition, Role):
# Condition is a role. Transition may be triggered if the user has
# this role.
return user.has_role(self.condition.name, obj)
elif type(self.condition) == types.FunctionType:
return self.condition(wf, obj.appy())
elif type(self.condition) in (tuple, list):
# It is a list of roles and/or functions. Transition may be
# triggered if user has at least one of those roles and if all
# functions return True.
hasRole = None
for condition in self.condition:
# "Unwrap" role names from Role instances.
if isinstance(condition, Role): condition = condition.name
if isinstance(condition, basestring): # It is a role
if hasRole == None:
hasRole = False
if user.has_role(condition, obj):
hasRole = True
else: # It is a method
if not condition(wf, obj.appy()):
return False
if hasRole != False:
return True
def executeAction(self, obj, wf):
'''Executes the action related to this transition.'''
msg = ''
obj = obj.appy()
wf = wf.__instance__ # We need the prototypical instance here.
if type(self.action) in (tuple, list):
# We need to execute a list of actions
for act in self.action:
msgPart = act(wf, obj)
if msgPart: msg += msgPart
else: # We execute a single action only.
msgPart = self.action(wf, obj)
if msgPart: msg += msgPart
return msg
def trigger(self, transitionName, obj, wf, comment, doAction=True,
doNotify=True, doHistory=True, doSay=True):
'''This method triggers this transition on p_obj. The transition is
supposed to be triggerable (call to self.isTriggerable must have been
performed before calling this method). If p_doAction is False, the
action that must normally be executed after the transition has been
triggered will not be executed. If p_doNotify is False, the
email notifications that must normally be launched after the
transition has been triggered will not be launched. If p_doHistory is
False, there will be no trace from this transition triggering in the
workflow history. If p_doSay is False, we consider the transition is
trigger programmatically, and no message is returned to the user.'''
# Create the workflow_history dict if it does not exist.
if not hasattr(obj.aq_base, 'workflow_history'):
from persistent.mapping import PersistentMapping
obj.workflow_history = PersistentMapping()
# Create the event list if it does not exist in the dict
if not obj.workflow_history: obj.workflow_history['appy'] = ()
# Get the key where object history is stored (this overstructure is
# only there for backward compatibility reasons)
key = obj.workflow_history.keys()[0]
# Identify the target state for this transition
if self.isSingle():
targetState = self.states[1]
targetStateName = targetState.getName(wf)
else:
startState = obj.State(name=False)
for sState, tState in self.states:
if startState == sState:
targetState = tState
targetStateName = targetState.getName(wf)
break
# Create the event and add it in the object history
action = transitionName
if transitionName == '_init_': action = None
if not doHistory: comment = '_invisible_'
obj.addHistoryEvent(action, review_state=targetStateName,
comments=comment)
# Reindex the object if required. Not only security-related indexes
# (Allowed, State) need to be updated here.
if not obj.isTemporary(): obj.reindex()
# Execute the related action if needed
msg = ''
if doAction and self.action: msg = self.executeAction(obj, wf)
# Send notifications if needed
if doNotify and self.notify and obj.getTool(True).mailEnabled:
sendNotification(obj.appy(), self, transitionName, wf)
# Return a message to the user if needed
if not doSay or (transitionName == '_init_'): return
if not msg: msg = obj.translate('object_saved')
obj.say(msg)
class UiTransition:
'''Represents a widget that displays a transition.'''
pxView = Px('''<x>
<!-- Real button -->
<input if="transition.mayTrigger"
type="button" class="button" title=":transition.title"
style=":url('buttonTransition', bg=True)"
value=":ztool.truncateValue(transition.title)"
onclick=":'triggerTransition(%s,%s,%s)' % (q(formId), \
q(transition.name), q(transition.confirm))"/>
<!-- Fake button, explaining why the transition can't be triggered -->
<input type="button" class="button" if="not transition.mayTrigger"
style=":url('buttonFake', bg=True) + ';cursor: help'"
value=":ztool.truncateValue(transition.title)"
title=":'%s: %s' % (transition.title, transition.reason)"/>
</x>''')
def __init__(self, name, transition, obj, mayTrigger, ):
self.name = name
self.transition = transition
self.type = 'transition'
label = obj.getWorkflowLabel(name)
self.title = obj.translate(label)
if transition.confirm:
self.confirm = obj.translate('%s_confirm' % label)
else:
self.confirm = ''
# May this transition be triggered via the UI?
self.mayTrigger = True
self.reason = ''
if not mayTrigger:
self.mayTrigger = False
self.reason = mayTrigger.msg
# Require by the UiGroup.
self.colspan = 1
# ------------------------------------------------------------------------------
class Permission:
'''If you need to define a specific read or write permission for some field
on a gen-class, you use the specific boolean attrs
"specificReadPermission" or "specificWritePermission". When you want to
refer to those specific read or write permissions when
defining a workflow, for example, you need to use instances of
"ReadPermission" and "WritePermission", the 2 children classes of this
class. For example, if you need to refer to write permission of
attribute "t1" of class A, write: WritePermission("A.t1") or
WritePermission("x.y.A.t1") if class A is not in the same module as
where you instantiate the class.
Note that this holds only if you use attributes "specificReadPermission"
and "specificWritePermission" as booleans. When defining named
(string) permissions, for referring to it you simply use those strings,
you do not create instances of ReadPermission or WritePermission.'''
allowedChars = string.digits + string.letters + '_'
def __init__(self, fieldDescriptor):
self.fieldDescriptor = fieldDescriptor
def getName(self, wf, appName):
'''Returns the name of this permission.'''
className, fieldName = self.fieldDescriptor.rsplit('.', 1)
if className.find('.') == -1:
# The related class resides in the same module as the workflow
fullClassName= '%s_%s' % (wf.__module__.replace('.', '_'),className)
else:
# className contains the full package name of the class
fullClassName = className.replace('.', '_')
# Read or Write ?
if self.__class__.__name__ == 'ReadPermission': access = 'Read'
else: access = 'Write'
return '%s: %s %s %s' % (appName, access, fullClassName, fieldName)
class ReadPermission(Permission): pass
class WritePermission(Permission): pass
# Standard workflows -----------------------------------------------------------
class WorkflowAnonymous:
'''One-state workflow allowing anyone to consult and Manager to edit.'''
mgr = 'Manager'
o = 'Owner'
active = State({r:(mgr, 'Anonymous', 'Authenticated'), w:(mgr,o),d:(mgr,o)},
initial=True)
class WorkflowAuthenticated:
'''One-state workflow allowing authenticated users to consult and Manager
to edit.'''
mgr = 'Manager'
o = 'Owner'
active = State({r:(mgr, 'Authenticated'), w:(mgr,o), d:(mgr,o)},
initial=True)
class WorkflowOwner:
'''One-state workflow allowing only manager and owner to consult and
edit.'''
mgr = 'Manager'
o = 'Owner'
active = State({r:(mgr, o), w:(mgr, o), d:mgr}, initial=True)
# ------------------------------------------------------------------------------