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Diffstat (limited to 'cloudinit/net/tests/test_dhcp.py')
| -rw-r--r-- | cloudinit/net/tests/test_dhcp.py | 144 |
1 files changed, 144 insertions, 0 deletions
diff --git a/cloudinit/net/tests/test_dhcp.py b/cloudinit/net/tests/test_dhcp.py new file mode 100644 index 00000000..47d8d461 --- /dev/null +++ b/cloudinit/net/tests/test_dhcp.py @@ -0,0 +1,144 @@ +# This file is part of cloud-init. See LICENSE file for license information. + +import mock +import os +from textwrap import dedent + +from cloudinit.net.dhcp import ( + InvalidDHCPLeaseFileError, maybe_perform_dhcp_discovery, + parse_dhcp_lease_file, dhcp_discovery) +from cloudinit.util import ensure_file, write_file +from tests.unittests.helpers import CiTestCase + + +class TestParseDHCPLeasesFile(CiTestCase): + + def test_parse_empty_lease_file_errors(self): + """parse_dhcp_lease_file errors when file content is empty.""" + empty_file = self.tmp_path('leases') + ensure_file(empty_file) + with self.assertRaises(InvalidDHCPLeaseFileError) as context_manager: + parse_dhcp_lease_file(empty_file) + error = context_manager.exception + self.assertIn('Cannot parse empty dhcp lease file', str(error)) + + def test_parse_malformed_lease_file_content_errors(self): + """parse_dhcp_lease_file errors when file content isn't dhcp leases.""" + non_lease_file = self.tmp_path('leases') + write_file(non_lease_file, 'hi mom.') + with self.assertRaises(InvalidDHCPLeaseFileError) as context_manager: + parse_dhcp_lease_file(non_lease_file) + error = context_manager.exception + self.assertIn('Cannot parse dhcp lease file', str(error)) + + def test_parse_multiple_leases(self): + """parse_dhcp_lease_file returns a list of all leases within.""" + lease_file = self.tmp_path('leases') + content = dedent(""" + lease { + interface "wlp3s0"; + fixed-address 192.168.2.74; + option subnet-mask 255.255.255.0; + option routers 192.168.2.1; + renew 4 2017/07/27 18:02:30; + expire 5 2017/07/28 07:08:15; + } + lease { + interface "wlp3s0"; + fixed-address 192.168.2.74; + option subnet-mask 255.255.255.0; + option routers 192.168.2.1; + } + """) + expected = [ + {'interface': 'wlp3s0', 'fixed-address': '192.168.2.74', + 'subnet-mask': '255.255.255.0', 'routers': '192.168.2.1', + 'renew': '4 2017/07/27 18:02:30', + 'expire': '5 2017/07/28 07:08:15'}, + {'interface': 'wlp3s0', 'fixed-address': '192.168.2.74', + 'subnet-mask': '255.255.255.0', 'routers': '192.168.2.1'}] + write_file(lease_file, content) + self.assertItemsEqual(expected, parse_dhcp_lease_file(lease_file)) + + +class TestDHCPDiscoveryClean(CiTestCase): + with_logs = True + + @mock.patch('cloudinit.net.dhcp.find_fallback_nic') + def test_no_fallback_nic_found(self, m_fallback_nic): + """Log and do nothing when nic is absent and no fallback is found.""" + m_fallback_nic.return_value = None # No fallback nic found + self.assertEqual({}, maybe_perform_dhcp_discovery()) + self.assertIn( + 'Skip dhcp_discovery: Unable to find fallback nic.', + self.logs.getvalue()) + + def test_provided_nic_does_not_exist(self): + """When the provided nic doesn't exist, log a message and no-op.""" + self.assertEqual({}, maybe_perform_dhcp_discovery('idontexist')) + self.assertIn( + 'Skip dhcp_discovery: nic idontexist not found in get_devicelist.', + self.logs.getvalue()) + + @mock.patch('cloudinit.net.dhcp.util.which') + @mock.patch('cloudinit.net.dhcp.find_fallback_nic') + def test_absent_dhclient_command(self, m_fallback, m_which): + """When dhclient doesn't exist in the OS, log the issue and no-op.""" + m_fallback.return_value = 'eth9' + m_which.return_value = None # dhclient isn't found + self.assertEqual({}, maybe_perform_dhcp_discovery()) + self.assertIn( + 'Skip dhclient configuration: No dhclient command found.', + self.logs.getvalue()) + + @mock.patch('cloudinit.net.dhcp.dhcp_discovery') + @mock.patch('cloudinit.net.dhcp.util.which') + @mock.patch('cloudinit.net.dhcp.find_fallback_nic') + def test_dhclient_run_with_tmpdir(self, m_fallback, m_which, m_dhcp): + """maybe_perform_dhcp_discovery passes tmpdir to dhcp_discovery.""" + m_fallback.return_value = 'eth9' + m_which.return_value = '/sbin/dhclient' + m_dhcp.return_value = {'address': '192.168.2.2'} + self.assertEqual( + {'address': '192.168.2.2'}, maybe_perform_dhcp_discovery()) + m_dhcp.assert_called_once() + call = m_dhcp.call_args_list[0] + self.assertEqual('/sbin/dhclient', call[0][0]) + self.assertEqual('eth9', call[0][1]) + self.assertIn('/tmp/cloud-init-dhcp-', call[0][2]) + + @mock.patch('cloudinit.net.dhcp.util.subp') + def test_dhcp_discovery_run_in_sandbox(self, m_subp): + """dhcp_discovery brings up the interface and runs dhclient. + + It also returns the parsed dhcp.leases file generated in the sandbox. + """ + tmpdir = self.tmp_dir() + dhclient_script = os.path.join(tmpdir, 'dhclient.orig') + script_content = '#!/bin/bash\necho fake-dhclient' + write_file(dhclient_script, script_content, mode=0o755) + lease_content = dedent(""" + lease { + interface "eth9"; + fixed-address 192.168.2.74; + option subnet-mask 255.255.255.0; + option routers 192.168.2.1; + } + """) + lease_file = os.path.join(tmpdir, 'dhcp.leases') + write_file(lease_file, lease_content) + self.assertItemsEqual( + [{'interface': 'eth9', 'fixed-address': '192.168.2.74', + 'subnet-mask': '255.255.255.0', 'routers': '192.168.2.1'}], + dhcp_discovery(dhclient_script, 'eth9', tmpdir)) + # dhclient script got copied + with open(os.path.join(tmpdir, 'dhclient')) as stream: + self.assertEqual(script_content, stream.read()) + # Interface was brought up before dhclient called from sandbox + m_subp.assert_has_calls([ + mock.call( + ['ip', 'link', 'set', 'dev', 'eth9', 'up'], capture=True), + mock.call( + [os.path.join(tmpdir, 'dhclient'), '-1', '-v', '-lf', + lease_file, '-pf', os.path.join(tmpdir, 'dhclient.pid'), + 'eth9', '-sf', '/bin/true'], capture=True)]) |