Refactor add_address_alias into dbwrappers/dns.py

Lifting add_address_alias into dbwrappers/dns.py for reuse.

Change-Id: Ie61a8674d9def56843c8ef2d585f54230cb9e8e7
Addresses-Issue: Jira/AQUILON-6374
Reviewed-by: Tomasz Kotarba <Tomasz.Kotarba@morganstanley.com>
Tested-by: Aquilon Template Build testing and verification

lib/aquilon/worker/commands/add_address_alias.py

@@ -1,7 +1,7 @@
 # -*- cpy-indent-level: 4; indent-tabs-mode: nil -*-
 # ex: set expandtab softtabstop=4 shiftwidth=4:
 #
-# Copyright (C) 2008,2009,2010,2011,2012,2013,2014,2015,2016,2017,2018  Contributor
+# Copyright (C) 2008-2019  Contributor
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
@@ -16,11 +16,12 @@
 # limitations under the License.
 """Contains the logic for `aq add address alias`."""
 
-from aquilon.exceptions_ import ArgumentError
-from aquilon.aqdb.model import AddressAlias, Fqdn, ReservedName
+from aquilon.aqdb.model import (
+    Fqdn,
+)
 from aquilon.worker.broker import BrokerCommand
-from aquilon.worker.dbwrappers.grn import lookup_grn
 from aquilon.worker.dbwrappers.change_management import ChangeManagement
+from aquilon.worker.dbwrappers.dns import add_address_alias
 
 
 class CommandAddAddressAlias(BrokerCommand):
@@ -37,17 +38,6 @@ def render(self, session, logger, fqdn, dns_environment, target,
         dbfqdn = Fqdn.get_or_create(session, dns_environment=dns_environment,
                                     fqdn=fqdn)
 
-        if dbfqdn.dns_environment.is_default and \
-           dbfqdn.dns_domain.name == "ms.com":
-            raise ArgumentError("%s record in DNS domain ms.com, DNS "
-                                "environment %s is not allowed." %
-                                (AddressAlias._get_class_label(),
-                                 dbfqdn.dns_environment.name))
-
-        if dbfqdn.dns_domain.restricted:
-            raise ArgumentError("{0} is restricted, aliases are not allowed."
-                                .format(dbfqdn.dns_domain))
-
         dbtarget = Fqdn.get_unique(session, fqdn=target,
                                    dns_environment=target_environment,
                                    compel=True)
@@ -57,37 +47,11 @@ def render(self, session, logger, fqdn, dns_environment, target,
         cm.consider(dbtarget)
         cm.validate()
 
-        dbgrn = None
-        if grn or eon_id:
-            dbgrn = lookup_grn(session, grn, eon_id, logger=logger,
-                               config=self.config)
-
-        # Make sure all AddressAlias records under the same Fqdn has
-        # the same GRN.
-        for rec in dbfqdn.dns_records:
-            if isinstance(rec, AddressAlias):
-                if not dbgrn:
-                    dbgrn = rec.owner_grn
-                elif dbgrn != rec.owner_grn:
-                    raise ArgumentError("{0} with target {1} is set to a "
-                                        "different GRN."
-                                        .format(dbfqdn, rec.target.fqdn))
-                break
-
-        db_record = AddressAlias(fqdn=dbfqdn, target=dbtarget, ttl=ttl,
-                                 owner_grn=dbgrn, comments=comments,
-                                 require_grn=False)
-        session.add(db_record)
-
-        if exporter:
-            if any(
-                    dr != db_record and
-                    not isinstance(dr, ReservedName)
-                    for dr in dbfqdn.dns_records):
-                exporter.update(dbfqdn)
-            else:
-                exporter.create(dbfqdn)
-
-        session.flush()
+        add_address_alias(session, logger, config=self.config,
+                          dbsrcfqdn=dbfqdn,
+                          dbtargetfqdn=dbtarget,
+                          ttl=ttl, grn=grn, eon_id=eon_id,
+                          comments=comments, exporter=exporter,
+                          flush_session=True)
 
         return

lib/aquilon/worker/dbwrappers/dns.py

@@ -19,11 +19,11 @@
 
 import socket
 
-from sqlalchemy.orm import object_session, joinedload, lazyload
-from sqlalchemy.orm.exc import NoResultFound
-from sqlalchemy.sql import or_
-
-from aquilon.exceptions_ import ArgumentError, AquilonError, NotFoundException
+from aquilon.exceptions_ import (
+    AquilonError,
+    ArgumentError,
+    NotFoundException,
+)
 from aquilon.aqdb.model import (
     AddressAlias,
     AddressAssignment,
@@ -41,8 +41,17 @@
 )
 from aquilon.aqdb.model.dns_domain import parse_fqdn
 from aquilon.aqdb.model.network import get_net_id_from_ip
+from aquilon.worker.dbwrappers.grn import lookup_grn
 from aquilon.worker.dbwrappers.interface import check_ip_restrictions
 
+from sqlalchemy.orm import (
+    joinedload,
+    lazyload,
+    object_session,
+)
+from sqlalchemy.orm.exc import NoResultFound
+from sqlalchemy.sql import or_
+
 
 def delete_dns_record(dbdns_rec, locked=False, verify_assignments=False, exporter=None):
     """
@@ -516,3 +525,65 @@ def set_reverse_ptr(session, logger, dbdns_rec, reverse_ptr):
             raise ArgumentError(err)
     else:
         dbdns_rec.reverse_ptr = None
+
+
+def add_address_alias(session, logger, config, dbsrcfqdn, dbtargetfqdn,
+                      ttl, grn, eon_id, comments, exporter=None,
+                      flush_session=False):
+    """Add an address-alias record (from source and target FQDN DB objects).
+
+    Does not allow the addition of an address-alias into 'ms.com' in the
+    'internal' environment, nor the addition of an address-alias in restricted
+    DNS domains.
+
+    Ensures that all address-aliases have the same GRN where set.
+
+    Returns the newly created AddressAlias object on success, raises an
+    exception on error.
+    """
+
+    if (dbsrcfqdn.dns_environment.is_default and
+            dbsrcfqdn.dns_domain.name == 'ms.com'):
+        raise ArgumentError("{0:s} record in DNS domain ms.com, DNS "
+                            "environment {1:s} is not allowed."
+                            .format(AddressAlias._get_class_label(),
+                                    dbsrcfqdn.dns_environment.name))
+
+    if dbsrcfqdn.dns_domain.restricted:
+        raise ArgumentError("{0} is restricted, aliases are not allowed."
+                            .format(dbsrcfqdn.dns_domain))
+
+    # Make sure all AddressAlias records under the same FQDN have the
+    # same GRN (if set).
+    dbgrn = None
+    if grn or eon_id:
+        dbgrn = lookup_grn(session, grn, eon_id, logger=logger,
+                           config=config)
+
+    for rec in dbsrcfqdn.dns_records:
+        if isinstance(rec, AddressAlias):
+            if not dbgrn:
+                dbgrn = rec.owner_grn
+            elif dbgrn != rec.owner_grn:
+                raise ArgumentError("{0} with target {1} is set to a "
+                                    "different GRN."
+                                    .format(dbsrcfqdn, rec.target.fqdn))
+            break       # assume the rest are checked
+
+    dbaa = AddressAlias(fqdn=dbsrcfqdn, target=dbtargetfqdn, ttl=ttl,
+                        owner_grn=dbgrn, comments=comments,
+                        require_grn=False)
+    session.add(dbaa)
+
+    if exporter:
+        other_recs = [dr for dr in dbsrcfqdn.dns_records
+                      if dr != dbaa and not isinstance(dr, ReservedName)]
+        if other_recs:
+            exporter.update(dbsrcfqdn)
+        else:
+            exporter.create(dbsrcfqdn)
+
+    if flush_session:
+        session.flush()
+
+    return dbaa