History and versioning

Introduction

Plone versioning allows you to go back between older edits of the same content object.

Versioning allows you to restore and diff previous copies of the same content. More about CMFEditions here.

See also

Checking whether versioning is enabled

The following check is performed by update_versioning_before_edit and update_versioning_on_edit scripts:

pr = context.portal_repository

isVersionable = pr.isVersionable(context)

if pr.supportsPolicy(context, 'at_edit_autoversion') and isVersionable:
    # Versioning should work
    pass
else:
    # Something is wrong....
    pass

Inspecting versioning policies

Example:

portal_repository = context.portal_repository
map = portal_repository.getPolicyMap()
for i in map.items(): print i

Will output (inc. some custom content types):

('File Disease Description', ['at_edit_autoversion', 'version_on_revert'])
('Document', ['at_edit_autoversion', 'version_on_revert'])
('Free Text Disease Description', ['at_edit_autoversion', 'version_on_revert'])
('ATDocument', ['at_edit_autoversion', 'version_on_revert'])
('Diagnose Description', ['at_edit_autoversion', 'version_on_revert'])
('ATNewsItem', ['at_edit_autoversion', 'version_on_revert'])
('Link', ['at_edit_autoversion', 'version_on_revert'])
('News Item', ['at_edit_autoversion', 'version_on_revert'])
('Event', ['at_edit_autoversion', 'version_on_revert'])

How versioning (CMFEditions) works

Note

You might actually want to check out the package to get your web browser to properly read the file.

Getting the complete revision history for an object

You may find yourself needing to (programmatically) get some/all of a content object’s revision history. The content history view can be utilised to do this; this view is the same one that is visible through Plone’s web interface at @@contenthistory (or indirectly on @@historyview). This code works with Plone 4.1 and has been utilised for exporting raw content modification information:

from plone.app.layout.viewlets.content import ContentHistoryView
context = portal['front-page']
print ContentHistoryView(context, context.REQUEST).fullHistory()

If you want to run this from somewhere without a REQUEST available, such as the Plone/Zope debug console, then you’ll need to fake a request and access level accordingly. Note the subtle change to using ContentHistoryViewlet rather than ContentHistoryView - we need to avoid initialising an entire view because this involves component lookups (and thus, pain). We also need to fake our security as well to avoid anything being left out from the history.

from plone.app.layout.viewlets.content import ContentHistoryViewlet
from zope.publisher.browser import TestRequest
from AccessControl.SecurityManagement import newSecurityManager

admin = app.acl_users.getUser('webmaster')
request = TestRequest()
newSecurityManager(request,admin)

portal = app.ands
context = portal['front-page']
chv = ContentHistoryViewlet(context, request, None, None)
#These attributes are needed, the fullHistory() call fails otherwise
chv.navigation_root_url = chv.site_url = 'http://www.foo.com'
print chv.fullHistory()

The end result should look something like this, which has plenty of tasty morsels to pull apart and use:

[{'action': u'Edited',
  'actor': {'description': '',
            'fullname': 'admin',
            'has_email': False,
            'home_page': '',
            'language': '',
            'location': '',
            'username': 'admin'},
  'actor_home': 'http://www.foo.com/author/admin',
  'actorid': 'admin',
  'comments': u'Initial revision',
  'diff_current_url': 'http://foo/Plone5/front-page/@@history?one=current&two=0',
  'preview_url': 'http://foo/Plone5/front-page/versions_history_form?version_id=0#version_preview',
  'revert_url': 'http://foo/Plone5/front-page/revertversion',
  'time': 1321397285.980262,
  'transition_title': u'Edited',
  'type': 'versioning',
  'version_id': 0},
 {'action': 'publish',
  'actor': {'description': '',
            'fullname': '',
            'has_email': False,
            'home_page': '',
            'language': '',
            'location': '',
            'username': 'admin'},
  'actor_home': 'http://www.foo.com/author/admin',
  'actorid': 'admin',
  'comments': '',
  'review_state': 'published',
  'state_title': 'Published',
  'time': DateTime('2011/11/15 09:49:8.023381 GMT+10'),
  'transition_title': 'Publish',
  'type': 'workflow'},
 {'action': None,
  'actor': {'description': '',
            'fullname': '',
            'has_email': False,
            'home_page': '',
            'language': '',
            'location': '',
            'username': 'admin'},
  'actor_home': 'http://www.foo.com/author/admin',
  'actorid': 'admin',
  'comments': '',
  'review_state': 'private',
  'state_title': 'Private',
  'time': DateTime('2011/11/15 09:49:8.005597 GMT+10'),
  'transition_title': u'Create',
  'type': 'workflow'}]

For instance, you can determine who the last person to modify this Plone content was by looking at the first list element (and get all their details from the actor information). Refer to the source of plone.app.layout.viewlets.content for more information about ContentHistoryView, ContentHistoryViewlet and WorkflowHistoryViewlet. Using these other class definitions, you can see that you can get just the workflow history using .workflowHistory() or just the revision history using .revisionHistory().