Fix upgrade when Dogtag also upgraded from 10.2 -> 10.3

ipa-server-upgrade from pre-lightweight CAs version fails when
Dogtag is also being upgraded from pre-lightweight CAs version,
because Dogtag needs to be restarted after adding the lightweight
CAs container, before requesting information about the host
authority.

Move the addition of the Dogtag lightweight CAs container entry a
bit earlier in the upgrade procedure, ensuring restart.

Fixes: https://fedorahosted.org/freeipa/ticket/6011
Reviewed-By: Martin Babinsky <mbabinsk@redhat.com>

ipaserver/install/cainstance.py

@@ -1701,7 +1701,7 @@ def ensure_ldap_profiles_container():
     )
 
 def ensure_lightweight_cas_container():
-    ensure_entry(
+    return ensure_entry(
         DN(('ou', 'authorities'), ('ou', 'ca'), ('o', 'ipaca')),
         objectclass=['top', 'organizationalUnit'],
         ou=['authorities'],
@@ -1709,6 +1709,12 @@ def ensure_lightweight_cas_container():
 
 
 def ensure_entry(dn, **attrs):
+    """Ensure an entry exists.
+
+    If an entry with the given DN already exists, return ``False``,
+    otherwise add the entry and return ``True``.
+
+    """
     server_id = installutils.realm_to_serverid(api.env.realm)
     dogtag_uri = 'ldapi://%%2fvar%%2frun%%2fslapd-%s.socket' % server_id
 
@@ -1718,12 +1724,14 @@ def ensure_entry(dn, **attrs):
 
     try:
         conn.get_entry(dn)
+        return False
     except errors.NotFound:
         # entry doesn't exist; add it
         entry = conn.make_entry(dn, **attrs)
         conn.add_entry(entry)
-
-    conn.disconnect()
+        return True
+    finally:
+        conn.disconnect()
 
 
 def configure_profiles_acl():

ipaserver/install/server/upgrade.py

@@ -1747,6 +1747,7 @@ def upgrade_configuration():
         ca_enable_pkix(ca),
         ca_configure_profiles_acl(ca),
         ca_configure_lightweight_ca_acls(ca),
+        ca_ensure_lightweight_cas_container(ca),
         ca_add_default_ocsp_uri(ca),
     ])
 
@@ -1758,7 +1759,6 @@ def upgrade_configuration():
         except ipautil.CalledProcessError as e:
             root_logger.error("Failed to restart %s: %s", ca.service_name, e)
 
-    ca_ensure_lightweight_cas_container(ca)
     ca_enable_ldap_profile_subsystem(ca)
 
     # This step MUST be done after ca_enable_ldap_profile_subsystem and