[Openstack] [OpenStack][Nova] Help with libvirt unit-test - get_diagnostics command
Hello, I've been working on implementing the diagnostics command for libvirt - https://review.openstack.org/#/c/8839/ . Now i need to create the unit test for this new operation. I've been looking at the code to try and figure out an easy way to replicate this, but i'm a bit lost. What i need to do is simulate a connection to libvirt, create a fake instance with a predefined characteristics, retrieve the virtdomain and then verify the results from the get_diagnostics command. I'm more at loss as to how exactly do i setup a fake connection a create a fake instance? I thought about creating a dummy implementation as i've seen being used around the tests, however that doesn't give me any access to real method. Do note that I'm relatively new to python world, so there's a lot of things i can't grasp yes :s. Regards, Leander ___ Mailing list: https://launchpad.net/~openstack Post to : openstack@lists.launchpad.net Unsubscribe : https://launchpad.net/~openstack More help : https://help.launchpad.net/ListHelp
Re: [Openstack] [OpenStack][Nova] Help with libvirt unit-test - get_diagnostics command
On Fri, Jul 06, 2012 at 11:59:51AM +0100, Leander Bessa Beernaert wrote:
Hello,
I've been working on implementing the diagnostics command for libvirt -
https://review.openstack.org/#/c/8839/ . Now i need to create the unit test
for this new operation. I've been looking at the code to try and figure out
an easy way to replicate this, but i'm a bit lost.
What i need to do is simulate a connection to libvirt, create a fake
instance with a predefined characteristics, retrieve the virtdomain and
then verify the results from the get_diagnostics command. I'm more at loss
as to how exactly do i setup a fake connection a create a fake instance? I
thought about creating a dummy implementation as i've seen being used
around the tests, however that doesn't give me any access to real method.
Do note that I'm relatively new to python world, so there's a lot of things
i can't grasp yes :s.
As you say, figuring out the libvirt Nova test framework is not entirely
easy, particularly if you're new to Python / Nova. So to help you get
your patch through review, here is one suitable test case you can add to
test_libvirt.py for exercising the get_diagnostics API:
diff --git a/nova/tests/test_libvirt.py b/nova/tests/test_libvirt.py
index eed43b8..f3fa5ff 100644
--- a/nova/tests/test_libvirt.py
+++ b/nova/tests/test_libvirt.py
@@ -1938,6 +1938,91 @@ class LibvirtConnTestCase(test.TestCase):
got = jsonutils.loads(conn.get_cpu_info())
self.assertEqual(want, got)
+def test_diagnostic_full(self):
+xml =
+domain type='kvm'
+devices
+disk type='file'
+source file='filename'/
+target dev='vda' bus='virtio'/
+/disk
+disk type='block'
+source dev='/path/to/dev/1'/
+target dev='vdb' bus='virtio'/
+/disk
+interface type='network'
+mac address='52:54:00:a4:38:38'/
+source network='default'/
+target dev='vnet0'/
+/interface
+/devices
+/domain
+
+
+class DiagFakeDomain(FakeVirtDomain):
+
+def __init__(self):
+super(DiagFakeDomain, self).__init__(fake_xml=xml)
+
+def vcpus(self):
+return ([(0, 1, 1534000L, 0),
+ (1, 1, 164000L, 0),
+ (2, 1, 304000L, 0),
+ (3, 1, 142000L, 0)],
+[(True, False),
+ (True, False),
+ (True, False),
+ (True, False)])
+
+def blockStats(self, path):
+return (169L, 688640L, 0L, 0L, -1L)
+
+def interfaceStats(self, path):
+return (4408L, 82L, 0L, 0L, 0L, 0L, 0L, 0L)
+
+def memoryStats(self):
+return {'actual': 220160L, 'rss': 200164L}
+
+def maxMemory(self):
+return 280160L
+
+def fake_lookup_name(name):
+return DiagFakeDomain()
+
+self.mox.StubOutWithMock(libvirt_driver.LibvirtDriver, '_conn')
+libvirt_driver.LibvirtDriver._conn.lookupByName = fake_lookup_name
+
+conn = libvirt_driver.LibvirtDriver(False)
+actual = conn.get_diagnostics( { name: testvirt })
+expect = {'cpu0_time': 1534000L,
+ 'cpu1_time': 164000L,
+ 'cpu2_time': 304000L,
+ 'cpu3_time': 142000L,
+ 'vda_read': 688640L,
+ 'vda_read_req': 169L,
+ 'vda_write': 0L,
+ 'vda_write_req': 0L,
+ 'vda_errors': -1L,
+ 'vdb_read': 688640L,
+ 'vdb_read_req': 169L,
+ 'vdb_write': 0L,
+ 'vdb_write_req': 0L,
+ 'vdb_errors': -1L,
+ 'memory': 280160L,
+ 'memory-actual': 220160L,
+ 'memory-rss': 200164L,
+ 'vnet0_rx': 4408L,
+ 'vnet0_rx_drop': 0L,
+ 'vnet0_rx_errors': 0L,
+ 'vnet0_rx_packets': 82L,
+ 'vnet0_tx': 0L,
+ 'vnet0_tx_drop': 0L,
+ 'vnet0_tx_errors': 0L,
+ 'vnet0_tx_packets': 0L,
+ }
+
+self.assertEqual(actual, expect)
+
class HostStateTestCase(test.TestCase):
A description of what I'm doing here:
* First we mock up an XML document that describes our test
guest, with 2 disks and 1 NIC.
* We create the FakeVirtDomain() class which provides a stub
implementation of the various libvirt APIs that the
get_diagnostics method will call.
Re: [Openstack] [OpenStack][Nova] Help with libvirt unit-test - get_diagnostics command
Daniel, thank you very much for your help!
However, i'm running into my infamous import libvirt problem again when
running the tests (see output below), i really though i'd fixed that one
for sure -.-'.
==
ERROR: test_diagnostic_full (nova.tests.test_libvirt.LibvirtConnTestCase)
--
Traceback (most recent call last):
File /home/gsd/nova/nova/tests/test_libvirt.py, line 1923, in
test_diagnostic_full
actual = conn.get_diagnostics({name: testvirt})
File /home/gsd/nova/nova/virt/libvirt/driver.py, line 2678, in
get_diagnostics
return diagnostics.get_diagnostics(dom)
File /home/gsd/nova/nova/virt/libvirt/diagnostics.py, line 97, in
get_diagnostics
import libvirt
ImportError: No module named libvirt
On Fri, Jul 6, 2012 at 1:11 PM, Daniel P. Berrange berra...@redhat.comwrote:
On Fri, Jul 06, 2012 at 11:59:51AM +0100, Leander Bessa Beernaert wrote:
Hello,
I've been working on implementing the diagnostics command for libvirt -
https://review.openstack.org/#/c/8839/ . Now i need to create the unit
test
for this new operation. I've been looking at the code to try and figure
out
an easy way to replicate this, but i'm a bit lost.
What i need to do is simulate a connection to libvirt, create a fake
instance with a predefined characteristics, retrieve the virtdomain and
then verify the results from the get_diagnostics command. I'm more at
loss
as to how exactly do i setup a fake connection a create a fake instance?
I
thought about creating a dummy implementation as i've seen being used
around the tests, however that doesn't give me any access to real method.
Do note that I'm relatively new to python world, so there's a lot of
things
i can't grasp yes :s.
As you say, figuring out the libvirt Nova test framework is not entirely
easy, particularly if you're new to Python / Nova. So to help you get
your patch through review, here is one suitable test case you can add to
test_libvirt.py for exercising the get_diagnostics API:
diff --git a/nova/tests/test_libvirt.py b/nova/tests/test_libvirt.py
index eed43b8..f3fa5ff 100644
--- a/nova/tests/test_libvirt.py
+++ b/nova/tests/test_libvirt.py
@@ -1938,6 +1938,91 @@ class LibvirtConnTestCase(test.TestCase):
got = jsonutils.loads(conn.get_cpu_info())
self.assertEqual(want, got)
+def test_diagnostic_full(self):
+xml =
+domain type='kvm'
+devices
+disk type='file'
+source file='filename'/
+target dev='vda' bus='virtio'/
+/disk
+disk type='block'
+source dev='/path/to/dev/1'/
+target dev='vdb' bus='virtio'/
+/disk
+interface type='network'
+mac address='52:54:00:a4:38:38'/
+source network='default'/
+target dev='vnet0'/
+/interface
+/devices
+/domain
+
+
+class DiagFakeDomain(FakeVirtDomain):
+
+def __init__(self):
+super(DiagFakeDomain, self).__init__(fake_xml=xml)
+
+def vcpus(self):
+return ([(0, 1, 1534000L, 0),
+ (1, 1, 164000L, 0),
+ (2, 1, 304000L, 0),
+ (3, 1, 142000L, 0)],
+[(True, False),
+ (True, False),
+ (True, False),
+ (True, False)])
+
+def blockStats(self, path):
+return (169L, 688640L, 0L, 0L, -1L)
+
+def interfaceStats(self, path):
+return (4408L, 82L, 0L, 0L, 0L, 0L, 0L, 0L)
+
+def memoryStats(self):
+return {'actual': 220160L, 'rss': 200164L}
+
+def maxMemory(self):
+return 280160L
+
+def fake_lookup_name(name):
+return DiagFakeDomain()
+
+self.mox.StubOutWithMock(libvirt_driver.LibvirtDriver, '_conn')
+libvirt_driver.LibvirtDriver._conn.lookupByName = fake_lookup_name
+
+conn = libvirt_driver.LibvirtDriver(False)
+actual = conn.get_diagnostics( { name: testvirt })
+expect = {'cpu0_time': 1534000L,
+ 'cpu1_time': 164000L,
+ 'cpu2_time': 304000L,
+ 'cpu3_time': 142000L,
+ 'vda_read': 688640L,
+ 'vda_read_req': 169L,
+ 'vda_write': 0L,
+ 'vda_write_req': 0L,
+ 'vda_errors':
