1 #!/usr/bin/python 2 # Copyright 2017 The Chromium OS Authors. All rights reserved. 3 # Use of this source code is governed by a BSD-style license that can be 4 # found in the LICENSE file. 5 6 import os 7 import tempfile 8 import shutil 9 import unittest 10 from contextlib import contextmanager 11 12 import common 13 from autotest_lib.client.bin import utils 14 from autotest_lib.client.common_lib import error 15 from autotest_lib.site_utils import lxc 16 from autotest_lib.site_utils.lxc import constants 17 from autotest_lib.site_utils.lxc import unittest_http 18 from autotest_lib.site_utils.lxc import unittest_setup 19 from autotest_lib.site_utils.lxc import utils as lxc_utils 20 21 22 @unittest.skipIf(lxc.IS_MOBLAB, 'Zygotes are not supported on moblab.') 23 class ZygoteTests(unittest.TestCase): 24 """Unit tests for the Zygote class.""" 25 26 @classmethod 27 def setUpClass(cls): 28 cls.test_dir = tempfile.mkdtemp(dir=lxc.DEFAULT_CONTAINER_PATH, 29 prefix='zygote_unittest_') 30 31 # Check if a base container exists on this machine and download one if 32 # necessary. 33 image = lxc.BaseImage() 34 try: 35 cls.base_container = image.get() 36 cls.cleanup_base_container = False 37 except error.ContainerError: 38 image.setup() 39 cls.base_container = image.get() 40 cls.cleanup_base_container = True 41 assert(cls.base_container is not None) 42 43 # Set up the zygote host path. 44 cls.shared_host_dir = lxc.SharedHostDir( 45 os.path.join(cls.test_dir, 'host')) 46 47 48 @classmethod 49 def tearDownClass(cls): 50 cls.base_container = None 51 if not unittest_setup.config.skip_cleanup: 52 if cls.cleanup_base_container: 53 lxc.BaseImage().cleanup() 54 cls.shared_host_dir.cleanup() 55 shutil.rmtree(cls.test_dir) 56 57 58 def testCleanup(self): 59 """Verifies that the zygote cleans up after itself.""" 60 with self.createZygote() as zygote: 61 host_path = zygote.host_path 62 63 self.assertTrue(os.path.isdir(host_path)) 64 65 # Start/stop the zygote to exercise the host mounts. 66 zygote.start(wait_for_network=False) 67 zygote.stop() 68 69 # After the zygote is destroyed, verify that the host path is cleaned 70 # up. 71 self.assertFalse(os.path.isdir(host_path)) 72 73 74 def testCleanupWithUnboundHostDir(self): 75 """Verifies that cleanup works when the host dir is unbound.""" 76 with self.createZygote() as zygote: 77 host_path = zygote.host_path 78 79 self.assertTrue(os.path.isdir(host_path)) 80 # Don't start the zygote, so the host mount is not bound. 81 82 # After the zygote is destroyed, verify that the host path is cleaned 83 # up. 84 self.assertFalse(os.path.isdir(host_path)) 85 86 87 def testCleanupWithNoHostDir(self): 88 """Verifies that cleanup works when the host dir is missing.""" 89 with self.createZygote() as zygote: 90 host_path = zygote.host_path 91 92 utils.run('sudo rmdir %s' % zygote.host_path) 93 self.assertFalse(os.path.isdir(host_path)) 94 # Zygote destruction should yield no errors if the host path is 95 # missing. 96 97 98 def testHostDir(self): 99 """Verifies that the host dir on the container is created, and correctly 100 bind-mounted.""" 101 with self.createZygote() as zygote: 102 self.assertIsNotNone(zygote.host_path) 103 self.assertTrue(os.path.isdir(zygote.host_path)) 104 105 zygote.start(wait_for_network=False) 106 107 self.verifyBindMount( 108 zygote, 109 container_path=lxc.CONTAINER_HOST_DIR, 110 host_path=zygote.host_path) 111 112 113 def testHostDirExists(self): 114 """Verifies that the host dir is just mounted if it already exists.""" 115 # Pre-create the host dir and put a file in it. 116 test_host_path = os.path.join(self.shared_host_dir.path, 117 'testHostDirExists') 118 test_filename = 'test_file' 119 test_host_file = os.path.join(test_host_path, test_filename) 120 test_string = 'jackdaws love my big sphinx of quartz.' 121 os.makedirs(test_host_path) 122 with open(test_host_file, 'w') as f: 123 f.write(test_string) 124 125 # Sanity check 126 self.assertTrue(lxc_utils.path_exists(test_host_file)) 127 128 with self.createZygote(host_path=test_host_path) as zygote: 129 zygote.start(wait_for_network=False) 130 131 self.verifyBindMount( 132 zygote, 133 container_path=lxc.CONTAINER_HOST_DIR, 134 host_path=zygote.host_path) 135 136 # Verify that the old directory contents was preserved. 137 cmd = 'cat %s' % os.path.join(lxc.CONTAINER_HOST_DIR, 138 test_filename) 139 test_output = zygote.attach_run(cmd).stdout.strip() 140 self.assertEqual(test_string, test_output) 141 142 143 def testInstallSsp(self): 144 """Verifies that installing the ssp in the container works.""" 145 # Hard-coded path to some golden data for this test. 146 test_ssp = os.path.join( 147 common.autotest_dir, 148 'site_utils', 'lxc', 'test', 'test_ssp.tar.bz2') 149 # Create a container, install the self-served ssp, then check that it is 150 # installed into the container correctly. 151 with self.createZygote() as zygote: 152 # Note: start the zygote first, then install the SSP. This mimics 153 # the way things would work in the production environment. 154 zygote.start(wait_for_network=False) 155 with unittest_http.serve_locally(test_ssp) as url: 156 zygote.install_ssp(url) 157 158 # The test ssp just contains a couple of text files, in known 159 # locations. Verify the location and content of those files in the 160 # container. 161 cat = lambda path: zygote.attach_run('cat %s' % path).stdout 162 test0 = cat(os.path.join(constants.CONTAINER_AUTOTEST_DIR, 163 'test.0')) 164 test1 = cat(os.path.join(constants.CONTAINER_AUTOTEST_DIR, 165 'dir0', 'test.1')) 166 self.assertEquals('the five boxing wizards jumped quickly', 167 test0) 168 self.assertEquals('the quick brown fox jumps over the lazy dog', 169 test1) 170 171 172 def testInstallControlFile(self): 173 """Verifies that installing a control file in the container works.""" 174 _unused, tmpfile = tempfile.mkstemp() 175 with self.createZygote() as zygote: 176 # Note: start the zygote first. This mimics the way things would 177 # work in the production environment. 178 zygote.start(wait_for_network=False) 179 zygote.install_control_file(tmpfile) 180 # Verify that the file is found in the zygote. 181 zygote.attach_run( 182 'test -f %s' % os.path.join(lxc.CONTROL_TEMP_PATH, 183 os.path.basename(tmpfile))) 184 185 186 def testCopyFile(self): 187 """Verifies that files are correctly copied into the container.""" 188 control_string = 'amazingly few discotheques provide jukeboxes' 189 with tempfile.NamedTemporaryFile() as tmpfile: 190 tmpfile.write(control_string) 191 tmpfile.flush() 192 193 with self.createZygote() as zygote: 194 dst = os.path.join(constants.CONTAINER_AUTOTEST_DIR, 195 os.path.basename(tmpfile.name)) 196 zygote.start(wait_for_network=False) 197 zygote.copy(tmpfile.name, dst) 198 # Verify the file content. 199 test_string = zygote.attach_run('cat %s' % dst).stdout 200 self.assertEquals(control_string, test_string) 201 202 203 def testCopyDirectory(self): 204 """Verifies that directories are correctly copied into the container.""" 205 control_string = 'pack my box with five dozen liquor jugs' 206 with lxc_utils.TempDir() as tmpdir: 207 fd, tmpfile = tempfile.mkstemp(dir=tmpdir) 208 f = os.fdopen(fd, 'w') 209 f.write(control_string) 210 f.close() 211 212 with self.createZygote() as zygote: 213 dst = os.path.join(constants.CONTAINER_AUTOTEST_DIR, 214 os.path.basename(tmpdir)) 215 zygote.start(wait_for_network=False) 216 zygote.copy(tmpdir, dst) 217 # Verify the file content. 218 test_file = os.path.join(dst, os.path.basename(tmpfile)) 219 test_string = zygote.attach_run('cat %s' % test_file).stdout 220 self.assertEquals(control_string, test_string) 221 222 223 def testFindHostMount(self): 224 """Verifies that zygotes pick up the correct host dirs.""" 225 with self.createZygote() as zygote0: 226 # Not a clone, this just instantiates zygote1 on top of the LXC 227 # container created by zygote0. 228 zygote1 = lxc.Zygote(container_path=zygote0.container_path, 229 name=zygote0.name, 230 attribute_values={}) 231 # Verify that the new zygote picked up the correct host path 232 # from the existing LXC container. 233 self.assertEquals(zygote0.host_path, zygote1.host_path) 234 self.assertEquals(zygote0.host_path_ro, zygote1.host_path_ro) 235 236 237 def testDetectExistingMounts(self): 238 """Verifies that host mounts are properly reconstructed. 239 240 When a Zygote is instantiated on top of an already-running container, 241 any previously-created bind mounts have to be detected. This enables 242 proper cleanup later. 243 """ 244 with lxc_utils.TempDir() as tmpdir, self.createZygote() as zygote0: 245 zygote0.start(wait_for_network=False) 246 # Create a bind mounted directory. 247 zygote0.mount_dir(tmpdir, 'foo') 248 # Create another zygote on top of the existing container. 249 zygote1 = lxc.Zygote(container_path=zygote0.container_path, 250 name=zygote0.name, 251 attribute_values={}) 252 # Verify that the new zygote contains the same bind mounts. 253 self.assertEqual(zygote0.mounts, zygote1.mounts) 254 255 256 def testMountDirectory(self): 257 """Verifies that read-write mounts work.""" 258 with lxc_utils.TempDir() as tmpdir, self.createZygote() as zygote: 259 dst = '/testMountDirectory/testMount' 260 zygote.start(wait_for_network=False) 261 zygote.mount_dir(tmpdir, dst, readonly=False) 262 263 # Verify that the mount point is correctly bound, and is read-write. 264 self.verifyBindMount(zygote, dst, tmpdir) 265 zygote.attach_run('test -r {0} -a -w {0}'.format(dst)) 266 267 268 def testMountDirectoryReadOnly(self): 269 """Verifies that read-only mounts are mounted, and read-only.""" 270 with lxc_utils.TempDir() as tmpdir, self.createZygote() as zygote: 271 dst = '/testMountDirectoryReadOnly/testMount' 272 zygote.start(wait_for_network=False) 273 zygote.mount_dir(tmpdir, dst, readonly=True) 274 275 # Verify that the mount point is correctly bound, and is read-only. 276 self.verifyBindMount(zygote, dst, tmpdir) 277 try: 278 zygote.attach_run('test -r {0} -a ! -w {0}'.format(dst)) 279 except error.CmdError: 280 self.fail('Bind mount is not read-only') 281 282 283 def testMountDirectoryRelativePath(self): 284 """Verifies that relative-path mounts work.""" 285 with lxc_utils.TempDir() as tmpdir, self.createZygote() as zygote: 286 dst = 'testMountDirectoryRelativePath/testMount' 287 zygote.start(wait_for_network=False) 288 zygote.mount_dir(tmpdir, dst, readonly=True) 289 290 # Verify that the mount points is correctly bound.. 291 self.verifyBindMount(zygote, dst, tmpdir) 292 293 294 @contextmanager 295 def createZygote(self, 296 name = None, 297 attribute_values = None, 298 snapshot = True, 299 host_path = None): 300 """Clones a zygote from the test base container. 301 Use this to ensure that zygotes got properly cleaned up after each test. 302 303 @param container_path: The LXC path for the new container. 304 @param host_path: The host path for the new container. 305 @param name: The name of the new container. 306 @param attribute_values: Any attribute values for the new container. 307 @param snapshot: Whether to create a snapshot clone. 308 """ 309 if name is None: 310 name = self.id().split('.')[-1] 311 if host_path is None: 312 host_path = os.path.join(self.shared_host_dir.path, name) 313 if attribute_values is None: 314 attribute_values = {} 315 zygote = lxc.Zygote(self.test_dir, 316 name, 317 attribute_values, 318 self.base_container, 319 snapshot, 320 host_path) 321 try: 322 yield zygote 323 finally: 324 if not unittest_setup.config.skip_cleanup: 325 zygote.destroy() 326 327 328 def verifyBindMount(self, container, container_path, host_path): 329 """Verifies that a given path in a container is bind-mounted to a given 330 path in the host system. 331 332 @param container: The Container instance to be tested. 333 @param container_path: The path in the container to compare. 334 @param host_path: The path in the host system to compare. 335 """ 336 container_inode = (container.attach_run('ls -id %s' % container_path) 337 .stdout.split()[0]) 338 host_inode = utils.run('ls -id %s' % host_path).stdout.split()[0] 339 # Compare the container and host inodes - they should match. 340 self.assertEqual(container_inode, host_inode) 341 342 343 if __name__ == '__main__': 344 unittest_setup.setup() 345 unittest.main() 346
