Allow to ignore ip command errors

Change-Id: I8d7c77a5f9934b5e835752ce05100f86591c4ec6

tobiko/shell/ip.py

@@ -16,11 +16,15 @@
 from __future__ import absolute_import
 
 import netaddr
+from oslo_log import log
 
 import tobiko
 from tobiko.shell import sh
 
 
+LOG = log.getLogger(__name__)
+
+
 class IpError(tobiko.TobikoException):
     message = ("Unable to get IP addresses from host "
                "(exit_status={exit_status!r}): {error!s}")
@@ -66,8 +70,8 @@ def list_ip_addresses(ip_version=None, scope=None, **execute_params):
 
 
 def list_network_namespaces(**execute_params):
-    output = execute_ip(['-o', 'netns', 'list'], **execute_params)
     namespaces = tobiko.Selection()
+    output = execute_ip(['-o', 'netns', 'list'], **execute_params)
     if output:
         for line in output.splitlines():
             fields = line.strip().split()
@@ -76,10 +80,18 @@ def list_network_namespaces(**execute_params):
     return namespaces
 
 
-def execute_ip(ifconfig_args, **execute_params):
+IP_COMMAND = sh.shell_command(['/sbin/ip'])
-    command = ['/sbin/ip'] + ifconfig_args
+
+
+def execute_ip(ifconfig_args, ip_command=None, ignore_errors=False,
+               **execute_params):
+    if ip_command:
+        ip_command = sh.shell_command(ip_command)
+    else:
+        ip_command = IP_COMMAND
+    command = ip_command + ifconfig_args
     result = sh.execute(command, stdin=False, stdout=True, stderr=True,
                         expect_exit_status=None, **execute_params)
-    if result.exit_status:
+    if not ignore_errors and result.exit_status:
         raise IpError(error=result.stderr, exit_status=result.exit_status)
     return result.stdout

tobiko/tests/functional/shell/fixtures.py

@@ -13,6 +13,7 @@ class NetworkNamespaceFixture(tobiko.SharedFixture):
     def setup_fixture(self):
         for node in topology.list_openstack_nodes():
             network_namespaces = ip.list_network_namespaces(
+                ignore_errors=True,
                 ssh_client=node.ssh_client)
             if network_namespaces:
                 self.network_namespace = network_namespaces.first

tobiko/tests/functional/shell/test_ip.py

@@ -115,6 +115,15 @@ class IpTest(testtools.TestCase):
     def test_list_ip_addresses_with_namespace_and_scope(self):
         self.test_list_ip_addresses_with_namespace(scope='global')
 
+    def test_list_ip_addresses_with_failing_command(self):
+        self.assertRaises(ip.IpError, ip.list_ip_addresses,
+                          ip_command=['false'],
+                          ssh_client=self.namespace.ssh_client)
+
+    def test_list_ip_addresses_with_ignore_errors(self, **execute_params):
+        self.test_list_ip_addresses(ignore_errors=True, ip_command='false',
+                                    **execute_params)
+
     def test_list_namespaces(self, **execute_params):
         namespaces = ip.list_network_namespaces(**execute_params)
         self.assertIsInstance(namespaces, list)
@@ -133,3 +142,12 @@ class IpTest(testtools.TestCase):
         if ssh_client is None:
             self.skip('SSH proxy server not configured')
         self.test_list_namespaces(ssh_client=ssh_client)
+
+    def test_list_namespaces_with_failing_command(self):
+        self.assertRaises(ip.IpError, ip.list_network_namespaces,
+                          ip_command=['false'],
+                          ssh_client=self.namespace.ssh_client)
+
+    def test_list_namespaces_with_ignore_errors(self, **execute_params):
+        self.test_list_namespaces(ignore_errors=True, ip_command='false',
+                                  **execute_params)