z3c.objectpolicy 0.1

objectpolicy for Zope3

The objectpolicy package makes it easy to override the default zope.securitypolicy.zopepolicy on an object by object basis.

Contents

• Levels

• Basic Setup (for high level tests)

  • Let’s see a simple permission check

  • Now a more complicated, parent-child setup

  • Cleanup

• Basic Setup (for low level tests)

  • Let’s see a simple permission check

  • Now a more complicated, parent-child setup

  • Cleanup

• CHANGES

The objectpolicy package makes it easy to override the default zope.securitypolicy.zopepolicy on an object by object basis.

By default all objects use the zopepolicy. Objects that want to have their own policy should have a marker interface IObjectPolicyMarker and have an adapter to IObjectPolicy.

Levels

There are two levels supported.

• The low level is the SecurityMap.getCell level. Here are the permissions stored by principal or role. This works also with ZopePolicy as the security policy. Uses Allow, Deny, Unset values. Permissions descend (with ZopePolicy) to child objects or views. See:

  • IObjectPolicy.getPrincipalPermission

  • IObjectPolicy.getRolePermission

  • lowlevel.txt

  Installation: Drop the z3c.objectpolicy-configure.zcml in the instance/etc folder.

• The high level is the ISecurityPolicy.checkPermission level. Here the permission is usually summarized for the principal by it’s roles, groups and object parent/child relations. ZopePolicy has to be overridden by the ObjectsPolicy security policy. Permissions do not decend to child objects or views. Uses True – access, False – no access values. See:

  • IObjectPolicy.checkPermission

  • highlevel.txt

  Installation: Override ZopePolicy in the instance/etc/securitypolicy.zcml

Basic Setup (for high level tests)

Good but not perfect example is the the user needs to be able to modify it’s own properties problem.

>>> from zope import interface, component
>>> from zope.annotation.interfaces import IAttributeAnnotatable
>>> from zope.container.interfaces import IContained
>>> from zope.container.contained import Contained
>>> from z3c.objectpolicy.interfaces import IObjectPolicy
>>> from z3c.objectpolicy.interfaces import IObjectPolicyMarker
>>> class IPerson(interface.Interface):
...     """a person interface for a person class"""
...
>>> class Person(Contained):
...     interface.implements(
...         IObjectPolicyMarker,
...         IAttributeAnnotatable,
...         IPerson)
...     def __init__(self, id, name):
...         self.id = id
...         self.name = name
...         self.groups = []
...
>>> class otherKlass(object):
...     #This class does NOT implement IObjectPolicyMarker
...     interface.implements(
...         IAttributeAnnotatable)
...     def __init__(self, id):
...         self.id = id

These permissions will be allowed for the principal on the Person object if the current principal == Person

>>> ALLOW_FOR_SELF = ["zope.View",
...                   "zope.app.dublincore.view",
...                   "zope.ManageContent"]

Counter to see how many times the adapter fires

>>> TRIP_WIRE = 0

This is the custom policy adapter which determines the permission. Watch out, this is just a little bit different from the lowlevel example!

>>> from z3c.objectpolicy.objectpolicy import DefaultObjectPolicyAdapter
>>> class PersonPolicy(DefaultObjectPolicyAdapter):
...     component.adapts(IPerson)
...     interface.implements(IObjectPolicy)
...
...     def __init__(self, context):
...         #context is a Person
...         self.context = context
...
...     def checkPermission(self, manager, permissionid):
...         #print permissionid, str(self.context)
...         return self.checkPermissionForParticipation(manager, permissionid)
...
...     def checkPermissionForParticipant(self, manager, principal, permissionid):
...         global TRIP_WIRE
...         TRIP_WIRE += 1
...         if principal.id == self.context.id:
...             #we have the same Person in the participation
...             if permissionid in ALLOW_FOR_SELF:
...                 #we have the Person and the Permission
...                 return True
...
...         #no Person or Permission found
...         #return the Z3 default permissions
...         return super(PersonPolicy, self).checkPermissionForParticipant(
...             manager, principal, permissionid)
...
>>> component.provideAdapter(PersonPolicy)

Install the ObjectPolicy, setup for testing.

>>> from z3c.objectpolicy.objectpolicy import ObjectPrincipalPermissionManager
>>> from z3c.objectpolicy.objectpolicy import ObjectRolePermissionManager
>>> from z3c.objectpolicy.objectpolicy import ObjectPolicy

>>> component.provideAdapter(ObjectPrincipalPermissionManager)
>>> component.provideAdapter(ObjectRolePermissionManager)

>>> bela = Person('b-id', 'bela')
>>> joe = Person('j-id', 'joe')

>>> class Participation:
...     interaction = None
>>> participation = Participation()
>>> participation.principal = joe
>>> import zope.security.management
>>> oldPolicy = zope.security.management.setSecurityPolicy(ObjectPolicy)
>>> zope.security.management.endInteraction()
>>> zope.security.management.newInteraction(participation)
>>> interaction = zope.security.management.getInteraction()

Let’s see a simple permission check

joe has ManageContent access to joe without granting any permission

>>> interaction.checkPermission('zope.ManageContent', joe)
True
>>> TRIP_WIRE
1

joe has no SomePermission access to joe because that’s not listed in ALLOW_FOR_SELF

>>> interaction.checkPermission('myapp.SomePermission', joe)
False
>>> TRIP_WIRE
2

joe has NO ManageContent access to bela

>>> interaction.checkPermission('zope.ManageContent', bela)
False
>>> TRIP_WIRE
3

>>> from zope.securitypolicy.interfaces import IPrincipalPermissionManager
>>> prinperBela = IPrincipalPermissionManager(bela)
>>> prinperJoe = IPrincipalPermissionManager(joe)
>>> prinperBela.grantPermissionToPrincipal('zope.ManageContent', 'j-id')

When we grant permission joe to bela, joe has ManageContent access to bela

>>> interaction.checkPermission('zope.ManageContent', bela)
True
>>> TRIP_WIRE
4

Granting permission works for any arbitrary permission also

>>> prinperJoe.grantPermissionToPrincipal('myapp.SomePermission', 'j-id')
>>> interaction.checkPermission('myapp.SomePermission', joe)
True
>>> TRIP_WIRE
5

Objects without IObjectPolicyMarker behave as before. Without granting – no permission

>>> otherObject = otherKlass('o-id')
>>> prinperOther = IPrincipalPermissionManager(otherObject)
>>> interaction.checkPermission('zope.ManageContent', otherObject)
False
>>> TRIP_WIRE
5

>>> prinperOther.grantPermissionToPrincipal('zope.ManageContent', 'j-id')
>>> interaction.checkPermission('zope.ManageContent', otherObject)
True
>>> TRIP_WIRE
5

Check what’s up when the marker is there, but no adapter

>>> class otherKlassWOadapter(object):
...     #This class does NOT implement IObjectPolicyMarker
...     interface.implements(
...         IAttributeAnnotatable,
...         IObjectPolicyMarker)
...     def __init__(self, id):
...         self.id = id

>>> otherObjectWO = otherKlassWOadapter('oa-id')
>>> interaction.checkPermission('zope.ManageContent', otherObjectWO)
False

No permission, maybe something should be written to the log?

Now a more complicated, parent-child setup

>>> from zope.container.sample import SampleContainer
>>> from zope.location.location import locate
>>> class IPersonContainer(interface.Interface):
...     """a person container interface"""
...
>>> class PersonContainer(SampleContainer):
...     interface.implements(
...         IAttributeAnnotatable,
...         IPersonContainer)
...     def __init__(self, id):
...         self.id = id
...         super(PersonContainer, self).__init__()
...
>>> class BrowserView(object):
...     interface.implements(
...         IContained)
...

The layout is:

users(PersonContainer)

jack(Person)

editJack(BrowserView)

jane(Person)

editJane(BrowserView)

>>> users = PersonContainer('users')
>>> jack = Person('jack-id','jack')
>>> users['jack'] = jack
>>> locate(jack, users, 'jack')
>>> jane = Person('jane-id','jane')
>>> users['jane'] = jane
>>> locate(jane, users, 'jane')

>>> editJack = BrowserView()
>>> locate(editJack, jack, None)
>>> editJane = BrowserView()
>>> locate(editJane, jane, None)

>>> prinperUsers = IPrincipalPermissionManager(users)
>>> prinperJack = IPrincipalPermissionManager(jack)
>>> prinperJane = IPrincipalPermissionManager(jane)

>>> participation = Participation()

The principal acting is jack

>>> participation.principal = jack
>>> zope.security.management.endInteraction()
>>> zope.security.management.newInteraction(participation)
>>> interaction = zope.security.management.getInteraction()

When we don’t grant permission, only jack has permission to itself and to it’s editView.

>>> interaction.checkPermission('zope.ManageContent', users)
False
>>> interaction.checkPermission('zope.ManageContent', jack)
True
>>> interaction.checkPermission('zope.ManageContent', editJack)
False
>>> interaction.checkPermission('zope.ManageContent', jane)
False
>>> interaction.checkPermission('zope.ManageContent', editJane)
False

When we grant jane permission, jack still has the same.

>>> prinperUsers.grantPermissionToPrincipal('zope.ManageContent', 'jane-id')
>>> interaction.checkPermission('zope.ManageContent', users)
False
>>> interaction.checkPermission('zope.ManageContent', jack)
True
>>> interaction.checkPermission('zope.ManageContent', editJack)
False
>>> interaction.checkPermission('zope.ManageContent', jane)
False
>>> interaction.checkPermission('zope.ManageContent', editJane)
False

When we grant jack permission, he will have permission for the whole pack.

>>> prinperUsers.grantPermissionToPrincipal('zope.ManageContent', 'jack-id')
>>> interaction.checkPermission('zope.ManageContent', users)
True
>>> interaction.checkPermission('zope.ManageContent', jack)
True
>>> interaction.checkPermission('zope.ManageContent', editJack)
True
>>> interaction.checkPermission('zope.ManageContent', jane)
True
>>> interaction.checkPermission('zope.ManageContent', editJane)
True

Cleanup

We clean up the changes we made in these examples:

>>> zope.security.management.endInteraction()
>>> ignore = zope.security.management.setSecurityPolicy(oldPolicy)

Basic Setup (for low level tests)

Good but not perfect example is the the user needs to be able to modify it’s own properties problem.

>>> from zope import interface, component
>>> from zope.annotation.interfaces import IAttributeAnnotatable
>>> from zope.container.interfaces import IContained
>>> from zope.container.contained import Contained
>>> from z3c.objectpolicy.interfaces import IObjectPolicy
>>> from z3c.objectpolicy.interfaces import IObjectPolicyMarker
>>> class IPerson(interface.Interface):
...     """a person interface for a person class"""
...
>>> class Person(Contained):
...     interface.implements(
...         IObjectPolicyMarker,
...         IAttributeAnnotatable,
...         IPerson)
...     def __init__(self, id, name):
...         self.id = id
...         self.name = name
...         self.groups = []
...
>>> class otherKlass(object):
...     #This class does NOT implement IObjectPolicyMarker
...     interface.implements(
...         IAttributeAnnotatable)
...     def __init__(self, id):
...         self.id = id

These permissions will be allowed for the principal on the Person object if the current principal == Person

>>> ALLOW_FOR_SELF = ["zope.View",
...                   "zope.app.dublincore.view",
...                   "zope.ManageContent"]

Counter to see how many times the adapter fires

>>> TRIP_WIRE = 0

This is the custom policy adapter which determines the permission.

>>> from zope.securitypolicy.interfaces import Allow, Deny, Unset
>>> from z3c.objectpolicy.objectpolicy import DefaultObjectPolicyAdapter
>>> class PersonPolicy(DefaultObjectPolicyAdapter):
...     component.adapts(IPerson)
...     interface.implements(IObjectPolicy)
...
...     def __init__(self, context):
...         #context is a Person
...         self.context = context
...
...     def getPrincipalPermission(self, manager, permissionid, principalid, default):
...         global TRIP_WIRE
...         TRIP_WIRE += 1
...         if principalid == self.context.id:
...             #we have the same Person in the participation
...             if permissionid in ALLOW_FOR_SELF:
...                 #we have the Person and the Permission
...                 return Allow
...
...         #no Person or Permission found
...         #return the Z3 default permissions
...         return super(PersonPolicy, self).getPrincipalPermission(
...             manager, permissionid, principalid, default)
...
>>> component.provideAdapter(PersonPolicy)

Install the ObjectPolicy, setup for testing.

>>> from z3c.objectpolicy.objectpolicy import ObjectPrincipalPermissionManager
>>> from z3c.objectpolicy.objectpolicy import ObjectRolePermissionManager

>>> component.provideAdapter(ObjectPrincipalPermissionManager)
>>> component.provideAdapter(ObjectRolePermissionManager)

>>> bela = Person('b-id', 'bela')
>>> joe = Person('j-id', 'joe')

>>> class Participation:
...     interaction = None
>>> participation = Participation()
>>> participation.principal = joe
>>> import zope.security.management
>>> from zope.securitypolicy.zopepolicy import ZopeSecurityPolicy
>>> oldPolicy = zope.security.management.setSecurityPolicy(ZopeSecurityPolicy)
>>> zope.security.management.endInteraction()
>>> zope.security.management.newInteraction(participation)
>>> interaction = zope.security.management.getInteraction()

Let’s see a simple permission check

joe has ManageContent access to joe without granting any permission

>>> interaction.checkPermission('zope.ManageContent', joe)
True
>>> TRIP_WIRE
1

joe has no SomePermission access to joe because that’s not listed in ALLOW_FOR_SELF

>>> interaction.checkPermission('myapp.SomePermission', joe)
False
>>> TRIP_WIRE
2

joe has NO ManageContent access to bela

>>> interaction.checkPermission('zope.ManageContent', bela)
False
>>> TRIP_WIRE
3

>>> from zope.securitypolicy.interfaces import IPrincipalPermissionManager
>>> prinperBela = IPrincipalPermissionManager(bela)
>>> prinperJoe = IPrincipalPermissionManager(joe)
>>> prinperBela.grantPermissionToPrincipal('zope.ManageContent', 'j-id')

When we grant permission joe to bela, joe has ManageContent access to bela

>>> interaction.checkPermission('zope.ManageContent', bela)
True
>>> TRIP_WIRE
4

Granting permission works for any arbitrary permission also

>>> prinperJoe.grantPermissionToPrincipal('myapp.SomePermission', 'j-id')
>>> interaction.checkPermission('myapp.SomePermission', joe)
True
>>> TRIP_WIRE
5

Objects without IObjectPolicyMarker behave as before. Without granting – no permission

>>> otherObject = otherKlass('o-id')
>>> prinperOther = IPrincipalPermissionManager(otherObject)
>>> interaction.checkPermission('zope.ManageContent', otherObject)
False
>>> TRIP_WIRE
5

>>> prinperOther.grantPermissionToPrincipal('zope.ManageContent', 'j-id')
>>> interaction.checkPermission('zope.ManageContent', otherObject)
True
>>> TRIP_WIRE
5

Check what’s up when the marker is there, but no adapter

>>> class otherKlassWOadapter(object):
...     #This class does NOT implement IObjectPolicyMarker
...     interface.implements(
...         IAttributeAnnotatable,
...         IObjectPolicyMarker)
...     def __init__(self, id):
...         self.id = id

>>> otherObjectWO = otherKlassWOadapter('oa-id')
>>> interaction.checkPermission('zope.ManageContent', otherObjectWO)
False

No permission, maybe something should be written to the log?

Now a more complicated, parent-child setup

>>> from zope.container.sample import SampleContainer
>>> from zope.location.location import locate
>>> class IPersonContainer(interface.Interface):
...     """a person container interface"""
...
>>> class PersonContainer(SampleContainer):
...     interface.implements(
...         IAttributeAnnotatable,
...         IPersonContainer)
...     def __init__(self, id):
...         self.id = id
...         super(PersonContainer, self).__init__()
...
>>> class BrowserView(object):
...     interface.implements(
...         IContained)
...

The layout is:

users(PersonContainer)

jack(Person)

editJack(BrowserView)

jane(Person)

editJane(BrowserView)

>>> users = PersonContainer('users')
>>> jack = Person('jack-id','jack')
>>> users['jack'] = jack
>>> locate(jack, users, 'jack')
>>> jane = Person('jane-id','jane')
>>> users['jane'] = jane
>>> locate(jane, users, 'jane')

>>> editJack = BrowserView()
>>> locate(editJack, jack, None)
>>> editJane = BrowserView()
>>> locate(editJane, jane, None)

>>> prinperUsers = IPrincipalPermissionManager(users)
>>> prinperJack = IPrincipalPermissionManager(jack)
>>> prinperJane = IPrincipalPermissionManager(jane)

>>> participation = Participation()

The principal acting is jack

>>> participation.principal = jack
>>> zope.security.management.endInteraction()
>>> zope.security.management.newInteraction(participation)
>>> interaction = zope.security.management.getInteraction()

When we don’t grant permission, only jack has permission to itself and to it’s editView.

>>> interaction.checkPermission('zope.ManageContent', users)
False
>>> interaction.checkPermission('zope.ManageContent', jack)
True
>>> interaction.checkPermission('zope.ManageContent', editJack)
True
>>> interaction.checkPermission('zope.ManageContent', jane)
False
>>> interaction.checkPermission('zope.ManageContent', editJane)
False

When we grant jane permission, jack still has the same.

>>> prinperUsers.grantPermissionToPrincipal('zope.ManageContent', 'jane-id')
>>> interaction.checkPermission('zope.ManageContent', users)
False
>>> interaction.checkPermission('zope.ManageContent', jack)
True
>>> interaction.checkPermission('zope.ManageContent', editJack)
True
>>> interaction.checkPermission('zope.ManageContent', jane)
False
>>> interaction.checkPermission('zope.ManageContent', editJane)
False

When we grant jack permission, he will have permission for the whole pack.

>>> prinperUsers.grantPermissionToPrincipal('zope.ManageContent', 'jack-id')
>>> interaction.checkPermission('zope.ManageContent', users)
True
>>> interaction.checkPermission('zope.ManageContent', jack)
True
>>> interaction.checkPermission('zope.ManageContent', editJack)
True
>>> interaction.checkPermission('zope.ManageContent', jane)
True
>>> interaction.checkPermission('zope.ManageContent', editJane)
True

Cleanup

We clean up the changes we made in these examples:

>>> zope.security.management.endInteraction()
>>> ignore = zope.security.management.setSecurityPolicy(oldPolicy)

CHANGES

0.1 (2010-08-10)

• Initial release.