Add plugin framework to LDAP updates.

There are two reasons for the plugin framework:
1. To provide a way of doing manual/complex LDAP changes without having
   to keep extending ldapupdate.py (like we did with managed entries).
2. Allows for better control of restarts.

There are two types of plugins, preop and postop. A preop plugin runs
before any file-based updates are loaded. A postop plugin runs after
all file-based updates are applied.

A preop plugin may update LDAP directly or craft update entries to be
applied with the file-based updates.

Either a preop or postop plugin may attempt to restart the dirsrv instance.
The instance is only restartable if ipa-ldap-updater is being executed
as root. A warning is printed if a restart is requested for a non-root
user.

Plugins are not executed by default. This is so we can use ldapupdate
to apply simple updates in commands like ipa-nis-manage.

https://fedorahosted.org/freeipa/ticket/1789
https://fedorahosted.org/freeipa/ticket/1790
https://fedorahosted.org/freeipa/ticket/2032

ipaserver/install/plugins/rename_managed.py

@@ -0,0 +1,132 @@
+# Authors:
+#   Rob Crittenden <rcritten@redhat.com>
+#
+# Copyright (C) 2011  Red Hat
+# see file 'COPYING' for use and warranty information
+#
+# This program 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.
+#
+# This program 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 this program.  If not, see <http://www.gnu.org/licenses/>.
+
+from ipaserver.install.plugins import PRE_UPDATE, POST_UPDATE, FIRST, LAST
+from ipaserver.install.plugins import PRE_UPDATE, POST_UPDATE, FIRST, LAST
+from ipaserver.install.plugins.baseupdate import PreUpdate, PostUpdate
+from ipalib.frontend import Updater
+from ipaserver.install.plugins import baseupdate
+from ipalib import api, errors
+from ipapython import ipautil
+import ldap as _ldap
+
+def entry_to_update(entry):
+    """
+    Convert an entry into a name/value pair list that looks like an update.
+
+    An entry is a dict.
+
+    An update is a list of name/value pairs.
+    """
+    update = []
+    for attr in entry.keys():
+        if isinstance(entry[attr], list):
+            for i in xrange(len(entry[attr])):
+                update.append('%s:%s' % (str(attr), str(entry[attr][i])))
+        else:
+            update.append('%s:%s' % (str(attr), str(entry[attr])))
+
+    return update
+
+def generate_update(ldap, deletes=False):
+    """
+    We need to separate the deletes that need to happen from the
+    new entries that need to be added.
+    """
+    suffix = ipautil.realm_to_suffix(api.env.realm)
+    searchfilter = '(objectclass=*)'
+    definitions_managed_entries = []
+    old_template_container = 'cn=etc,%s' % suffix
+    old_definition_container = 'cn=managed entries,cn=plugins,cn=config'
+    new = 'cn=Managed Entries,cn=etc,%s' % suffix
+    sub = ['cn=Definitions,', 'cn=Templates,']
+    new_managed_entries = []
+    old_templates = []
+    template = None
+    restart = False
+
+    # If the old entries don't exist the server has already been updated.
+    try:
+        (definitions_managed_entries, truncated) = ldap.find_entries(
+            searchfilter, ['*'], old_definition_container, _ldap.SCOPE_ONELEVEL, normalize=False
+        )
+    except errors.NotFound, e:
+        return (False, new_managed_entries)
+
+    for entry in definitions_managed_entries:
+        new_definition = {}
+        definition_managed_entry_updates = {}
+        if deletes:
+            old_definition = {'dn': str(entry[0]), 'deleteentry': ['dn: %s' % str(entry[0])]}
+            old_template = str(entry[1]['managedtemplate'][0])
+            definition_managed_entry_updates[old_definition['dn']] = old_definition
+            old_templates.append(old_template)
+        else:
+            entry[1]['managedtemplate'] = str(entry[1]['managedtemplate'][0].replace(old_template_container, sub[1] + new))
+            new_definition['dn'] = str(entry[0].replace(old_definition_container, sub[0] + new))
+            new_definition['default'] = entry_to_update(entry[1])
+            definition_managed_entry_updates[new_definition['dn']] = new_definition
+            new_managed_entries.append(definition_managed_entry_updates)
+    for old_template in old_templates: # Only happens when deletes is True
+        try:
+            (dn, template) = ldap.get_entry(old_template, ['*'], normalize=False)
+            dn = str(dn)
+            new_template = {}
+            template_managed_entry_updates = {}
+            old_template = {'dn': dn, 'deleteentry': ['dn: %s' % dn]}
+            new_template['dn'] = str(dn.replace(old_template_container, sub[1] + new))
+            new_template['default'] = entry_to_update(template)
+            template_managed_entry_updates[new_template['dn']] = new_template
+            template_managed_entry_updates[old_template['dn']] = old_template
+            new_managed_entries.append(template_managed_entry_updates)
+        except errors.NotFound, e:
+            pass
+
+    if len(new_managed_entries) > 0:
+        restart = True
+        new_managed_entries.sort(reverse=True)
+
+    return (restart, new_managed_entries)
+
+class update_managed_post_first(PreUpdate):
+    """
+    Update managed entries
+    """
+    order=FIRST
+
+    def execute(self, **options):
+        # Never need to restart with the pre-update changes
+        (ignore, new_managed_entries) = generate_update(self.obj.backend, False)
+
+        return (False, True, new_managed_entries)
+
+api.register(update_managed_post_first)
+
+class update_managed_post(PostUpdate):
+    """
+    Update managed entries
+    """
+    order=LAST
+
+    def execute(self, **options):
+        (restart, new_managed_entries) = generate_update(self.obj.backend, True)
+
+        return (restart, True, new_managed_entries)
+
+api.register(update_managed_post)