dns: move code shared by client and server to separate module

Move the shared code to a new ipalib.dns module.

https://fedorahosted.org/freeipa/ticket/4739

Reviewed-By: David Kupka <dkupka@redhat.com>

ipalib/dns.py

@@ -0,0 +1,100 @@
+# Authors:
+#   Martin Kosek <mkosek@redhat.com>
+#   Pavel Zuna <pzuna@redhat.com>
+#
+# Copyright (C) 2010  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/>.
+
+import re
+
+from ipalib import errors
+
+# dnsrecord param name formats
+record_name_format = '%srecord'
+
+
+def get_record_rrtype(name):
+    match = re.match('([^_]+)record$', name)
+    if match is None:
+        return None
+
+    return match.group(1).upper()
+
+
+def has_cli_options(cmd, options, no_option_msg, allow_empty_attrs=False):
+    sufficient = ('setattr', 'addattr', 'delattr', 'rename')
+    if any(k in options for k in sufficient):
+        return
+
+    has_options = False
+    for attr in options.keys():
+        obj_params = [
+            p.name for p in cmd.params()
+            if get_record_rrtype(p.name) or 'dnsrecord_part' in p.flags]
+        if attr in obj_params:
+            if options[attr] or allow_empty_attrs:
+                has_options = True
+                break
+
+    if not has_options:
+        raise errors.OptionError(no_option_msg)
+
+
+def get_rrparam_from_part(cmd, part_name):
+    """
+    Get an instance of DNSRecord parameter that has part_name as its part.
+    If such parameter is not found, None is returned
+
+    :param part_name Part parameter name
+    """
+    try:
+        param = cmd.params[part_name]
+
+        if not any(flag in param.flags for flag in
+                   ('dnsrecord_part', 'dnsrecord_extra')):
+            return None
+
+        # All DNS record part or extra parameters contain a name of its
+        # parent RR parameter in its hint attribute
+        rrparam = cmd.params[param.hint]
+    except (KeyError, AttributeError):
+        return None
+
+    return rrparam
+
+
+def iterate_rrparams_by_parts(cmd, kw, skip_extra=False):
+    """
+    Iterates through all DNSRecord instances that has at least one of its
+    parts or extra options in given dictionary. It returns the DNSRecord
+    instance only for the first occurence of part/extra option.
+
+    :param kw Dictionary with DNS record parts or extra options
+    :param skip_extra Skip DNS record extra options, yield only DNS records
+                      with a real record part
+    """
+    processed = []
+    for opt in kw:
+        rrparam = get_rrparam_from_part(cmd, opt)
+        if rrparam is None:
+            continue
+
+        if skip_extra and 'dnsrecord_extra' in cmd.params[opt].flags:
+            continue
+
+        if rrparam.name not in processed:
+            processed.append(rrparam.name)
+            yield rrparam