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

install/tools/ipa-ldap-updater

@@ -33,6 +33,7 @@ try:
     from ipaserver.install.upgradeinstance import IPAUpgrade
     from ipapython import sysrestore
     import krbV
+    from ipalib import api
     from ipapython.ipa_log_manager import *
 except ImportError:
     print >> sys.stderr, """\
@@ -49,15 +50,19 @@ def parse_options():
     parser = IPAOptionParser(usage=usage, formatter=config.IPAFormatter())
 
     parser.add_option("-d", "--debug", action="store_true", dest="debug",
-                      help="Display debugging information about the update(s)")
+                      help="Display debugging information about the update(s)",
+                      default=False)
     parser.add_option("-t", "--test", action="store_true", dest="test",
-                      help="Run through the update without changing anything")
+                      help="Run through the update without changing anything",
+                      default=False)
     parser.add_option("-y", dest="password",
                       help="File containing the Directory Manager password")
     parser.add_option("-l", '--ldapi', action="store_true", dest="ldapi",
                       default=False, help="Connect to the LDAP server using the ldapi socket")
     parser.add_option("-u", '--upgrade', action="store_true", dest="upgrade",
                       default=False, help="Upgrade an installed server in offline mode")
+    parser.add_option("-p", '--plugins', action="store_true", dest="plugins",
+                      default=False, help="Execute update plugins. Always true when applying all update files.")
     parser.add_option("-W", '--password', action="store_true",
                       dest="ask_password",
                       help="Prompt for the Directory Manager password")
@@ -78,6 +83,7 @@ def get_dirman_password():
 def main():
     badsyntax = False
     upgradefailed = False
+    run_plugins = False
 
     safe_options, options, args = parse_options()
 
@@ -96,14 +102,30 @@ def main():
             if dirman_password is None:
                 sys.exit("\nDirectory Manager password required")
 
+    if options.upgrade:
+        standard_logging_setup('/var/log/ipaupgrade.log', verbose=True, debug=options.debug, filemode='a')
+    else:
+        standard_logging_setup(None, verbose=True, debug=options.debug)
+
+    cfg = dict (
+        in_server=True,
+        context='updates',
+        debug=options.debug,
+    )
+    api.bootstrap(**cfg)
+    api.finalize()
+
     files = []
     if len(args) > 0:
         files = args
 
+    if len(files) < 1:
+        run_plugins = True
+
+    updates = None
     if options.upgrade:
         if os.getegid() != 0:
             sys.exit('Upgrade can only be done as root')
-        standard_logging_setup('/var/log/ipaupgrade.log', verbose=True, debug=options.debug, filemode='a')
         root_logger.debug('%s was invoked with arguments %s and options: %s' % (sys.argv[0], args, safe_options))
         realm = krbV.default_context().default_realm
         upgrade = IPAUpgrade(realm, files, live_run=not options.test)
@@ -112,21 +134,24 @@ def main():
         badsyntax = upgrade.badsyntax
         upgradefailed = upgrade.upgradefailed
     else:
-        standard_logging_setup(None, verbose=True, debug=options.debug)
-        ld = LDAPUpdate(dm_password=dirman_password, sub_dict={}, live_run=not options.test, ldapi=options.ldapi)
+        ld = LDAPUpdate(dm_password=dirman_password, sub_dict={}, live_run=not options.test, ldapi=options.ldapi, plugins=options.plugins or run_plugins)
         if len(files) < 1:
             files = ld.get_all_files(UPDATES_DIR)
         modified = ld.update(files)
 
     if badsyntax:
+        root_logger.info('Bad syntax detected in upgrade file(s).')
         print 'Bad syntax detected in upgrade file(s).'
         return 1
     elif upgradefailed:
+        root_logger.info('IPA upgrade failed.')
         print 'IPA upgrade failed.'
         return 1
     elif modified and options.test:
+        root_logger.info('Update complete, changes to be made, test mode')
         return 2
     else:
+        root_logger.info('Update complete')
         return 0
 
 try: