relocate tests/unittests/helpers.py to cloudinit/tests

This moves the base test case classes into into cloudinit/tests and
updates all the corresponding imports.

1 files changed, 395 insertions, 0 deletions

diff --git a/cloudinit/tests/helpers.py b/cloudinit/tests/helpers.py
new file mode 100644
index 00000000..28e26622
--- /dev/null
+++ b/cloudinit/tests/helpers.py
@@ -0,0 +1,395 @@
+# This file is part of cloud-init. See LICENSE file for license information.
+
+from __future__ import print_function
+
+import functools
+import json
+import logging
+import os
+import shutil
+import sys
+import tempfile
+import unittest
+
+import mock
+import six
+import unittest2
+
+try:
+    from contextlib import ExitStack
+except ImportError:
+    from contextlib2 import ExitStack
+
+from cloudinit import helpers as ch
+from cloudinit import util
+
+# Used for skipping tests
+SkipTest = unittest2.SkipTest
+
+# Used for detecting different python versions
+PY2 = False
+PY26 = False
+PY27 = False
+PY3 = False
+
+_PY_VER = sys.version_info
+_PY_MAJOR, _PY_MINOR, _PY_MICRO = _PY_VER[0:3]
+if (_PY_MAJOR, _PY_MINOR) <= (2, 6):
+    if (_PY_MAJOR, _PY_MINOR) == (2, 6):
+        PY26 = True
+    if (_PY_MAJOR, _PY_MINOR) >= (2, 0):
+        PY2 = True
+else:
+    if (_PY_MAJOR, _PY_MINOR) == (2, 7):
+        PY27 = True
+        PY2 = True
+    if (_PY_MAJOR, _PY_MINOR) >= (3, 0):
+        PY3 = True
+
+
+# Makes the old path start
+# with new base instead of whatever
+# it previously had
+def rebase_path(old_path, new_base):
+    if old_path.startswith(new_base):
+        # Already handled...
+        return old_path
+    # Retarget the base of that path
+    # to the new base instead of the
+    # old one...
+    path = os.path.join(new_base, old_path.lstrip("/"))
+    path = os.path.abspath(path)
+    return path
+
+
+# Can work on anything that takes a path as arguments
+def retarget_many_wrapper(new_base, am, old_func):
+    def wrapper(*args, **kwds):
+        n_args = list(args)
+        nam = am
+        if am == -1:
+            nam = len(n_args)
+        for i in range(0, nam):
+            path = args[i]
+            # patchOS() wraps various os and os.path functions, however in
+            # Python 3 some of these now accept file-descriptors (integers).
+            # That breaks rebase_path() so in lieu of a better solution, just
+            # don't rebase if we get a fd.
+            if isinstance(path, six.string_types):
+                n_args[i] = rebase_path(path, new_base)
+        return old_func(*n_args, **kwds)
+    return wrapper
+
+
+class TestCase(unittest2.TestCase):
+
+    def reset_global_state(self):
+        """Reset any global state to its original settings.
+
+        cloudinit caches some values in cloudinit.util.  Unit tests that
+        involved those cached paths were then subject to failure if the order
+        of invocation changed (LP: #1703697).
+
+        This function resets any of these global state variables to their
+        initial state.
+
+        In the future this should really be done with some registry that
+        can then be cleaned in a more obvious way.
+        """
+        util.PROC_CMDLINE = None
+        util._DNS_REDIRECT_IP = None
+        util._LSB_RELEASE = {}
+
+    def setUp(self):
+        super(TestCase, self).setUp()
+        self.reset_global_state()
+
+
+class CiTestCase(TestCase):
+    """This is the preferred test case base class unless user
+       needs other test case classes below."""
+
+    # Subclass overrides for specific test behavior
+    # Whether or not a unit test needs logfile setup
+    with_logs = False
+
+    def setUp(self):
+        super(CiTestCase, self).setUp()
+        if self.with_logs:
+            # Create a log handler so unit tests can search expected logs.
+            self.logger = logging.getLogger()
+            self.logs = six.StringIO()
+            formatter = logging.Formatter('%(levelname)s: %(message)s')
+            handler = logging.StreamHandler(self.logs)
+            handler.setFormatter(formatter)
+            self.old_handlers = self.logger.handlers
+            self.logger.handlers = [handler]
+
+    def tearDown(self):
+        if self.with_logs:
+            # Remove the handler we setup
+            logging.getLogger().handlers = self.old_handlers
+        super(CiTestCase, self).tearDown()
+
+    def tmp_dir(self, dir=None, cleanup=True):
+        # return a full path to a temporary directory that will be cleaned up.
+        if dir is None:
+            tmpd = tempfile.mkdtemp(
+                prefix="ci-%s." % self.__class__.__name__)
+        else:
+            tmpd = tempfile.mkdtemp(dir=dir)
+        self.addCleanup(functools.partial(shutil.rmtree, tmpd))
+        return tmpd
+
+    def tmp_path(self, path, dir=None):
+        # return an absolute path to 'path' under dir.
+        # if dir is None, one will be created with tmp_dir()
+        # the file is not created or modified.
+        if dir is None:
+            dir = self.tmp_dir()
+        return os.path.normpath(os.path.abspath(os.path.join(dir, path)))
+
+
+class ResourceUsingTestCase(CiTestCase):
+
+    def setUp(self):
+        super(ResourceUsingTestCase, self).setUp()
+        self.resource_path = None
+
+    def resourceLocation(self, subname=None):
+        if self.resource_path is None:
+            paths = [
+                os.path.join('tests', 'data'),
+                os.path.join('data'),
+                os.path.join(os.pardir, 'tests', 'data'),
+                os.path.join(os.pardir, 'data'),
+            ]
+            for p in paths:
+                if os.path.isdir(p):
+                    self.resource_path = p
+                    break
+        self.assertTrue((self.resource_path and
+                         os.path.isdir(self.resource_path)),
+                        msg="Unable to locate test resource data path!")
+        if not subname:
+            return self.resource_path
+        return os.path.join(self.resource_path, subname)
+
+    def readResource(self, name):
+        where = self.resourceLocation(name)
+        with open(where, 'r') as fh:
+            return fh.read()
+
+    def getCloudPaths(self, ds=None):
+        tmpdir = tempfile.mkdtemp()
+        self.addCleanup(shutil.rmtree, tmpdir)
+        cp = ch.Paths({'cloud_dir': tmpdir,
+                       'templates_dir': self.resourceLocation()},
+                      ds=ds)
+        return cp
+
+
+class FilesystemMockingTestCase(ResourceUsingTestCase):
+
+    def setUp(self):
+        super(FilesystemMockingTestCase, self).setUp()
+        self.patched_funcs = ExitStack()
+
+    def tearDown(self):
+        self.patched_funcs.close()
+        ResourceUsingTestCase.tearDown(self)
+
+    def replicateTestRoot(self, example_root, target_root):
+        real_root = self.resourceLocation()
+        real_root = os.path.join(real_root, 'roots', example_root)
+        for (dir_path, _dirnames, filenames) in os.walk(real_root):
+            real_path = dir_path
+            make_path = rebase_path(real_path[len(real_root):], target_root)
+            util.ensure_dir(make_path)
+            for f in filenames:
+                real_path = util.abs_join(real_path, f)
+                make_path = util.abs_join(make_path, f)
+                shutil.copy(real_path, make_path)
+
+    def patchUtils(self, new_root):
+        patch_funcs = {
+            util: [('write_file', 1),
+                   ('append_file', 1),
+                   ('load_file', 1),
+                   ('ensure_dir', 1),
+                   ('chmod', 1),
+                   ('delete_dir_contents', 1),
+                   ('del_file', 1),
+                   ('sym_link', -1),
+                   ('copy', -1)],
+        }
+        for (mod, funcs) in patch_funcs.items():
+            for (f, am) in funcs:
+                func = getattr(mod, f)
+                trap_func = retarget_many_wrapper(new_root, am, func)
+                self.patched_funcs.enter_context(
+                    mock.patch.object(mod, f, trap_func))
+
+        # Handle subprocess calls
+        func = getattr(util, 'subp')
+
+        def nsubp(*_args, **_kwargs):
+            return ('', '')
+
+        self.patched_funcs.enter_context(
+            mock.patch.object(util, 'subp', nsubp))
+
+        def null_func(*_args, **_kwargs):
+            return None
+
+        for f in ['chownbyid', 'chownbyname']:
+            self.patched_funcs.enter_context(
+                mock.patch.object(util, f, null_func))
+
+    def patchOS(self, new_root):
+        patch_funcs = {
+            os.path: [('isfile', 1), ('exists', 1),
+                      ('islink', 1), ('isdir', 1)],
+            os: [('listdir', 1), ('mkdir', 1),
+                 ('lstat', 1), ('symlink', 2)],
+        }
+        for (mod, funcs) in patch_funcs.items():
+            for f, nargs in funcs:
+                func = getattr(mod, f)
+                trap_func = retarget_many_wrapper(new_root, nargs, func)
+                self.patched_funcs.enter_context(
+                    mock.patch.object(mod, f, trap_func))
+
+    def patchOpen(self, new_root):
+        trap_func = retarget_many_wrapper(new_root, 1, open)
+        name = 'builtins.open' if PY3 else '__builtin__.open'
+        self.patched_funcs.enter_context(mock.patch(name, trap_func))
+
+    def patchStdoutAndStderr(self, stdout=None, stderr=None):
+        if stdout is not None:
+            self.patched_funcs.enter_context(
+                mock.patch.object(sys, 'stdout', stdout))
+        if stderr is not None:
+            self.patched_funcs.enter_context(
+                mock.patch.object(sys, 'stderr', stderr))
+
+    def reRoot(self, root=None):
+        if root is None:
+            root = self.tmp_dir()
+        self.patchUtils(root)
+        self.patchOS(root)
+        return root
+
+
+class HttprettyTestCase(CiTestCase):
+    # necessary as http_proxy gets in the way of httpretty
+    # https://github.com/gabrielfalcao/HTTPretty/issues/122
+
+    def setUp(self):
+        self.restore_proxy = os.environ.get('http_proxy')
+        if self.restore_proxy is not None:
+            del os.environ['http_proxy']
+        super(HttprettyTestCase, self).setUp()
+
+    def tearDown(self):
+        if self.restore_proxy:
+            os.environ['http_proxy'] = self.restore_proxy
+        super(HttprettyTestCase, self).tearDown()
+
+
+def populate_dir(path, files):
+    if not os.path.exists(path):
+        os.makedirs(path)
+    ret = []
+    for (name, content) in files.items():
+        p = os.path.sep.join([path, name])
+        util.ensure_dir(os.path.dirname(p))
+        with open(p, "wb") as fp:
+            if isinstance(content, six.binary_type):
+                fp.write(content)
+            else:
+                fp.write(content.encode('utf-8'))
+            fp.close()
+        ret.append(p)
+
+    return ret
+
+
+def dir2dict(startdir, prefix=None):
+    flist = {}
+    if prefix is None:
+        prefix = startdir
+    for root, dirs, files in os.walk(startdir):
+        for fname in files:
+            fpath = os.path.join(root, fname)
+            key = fpath[len(prefix):]
+            flist[key] = util.load_file(fpath)
+    return flist
+
+
+def json_dumps(data):
+    # print data in nicely formatted json.
+    return json.dumps(data, indent=1, sort_keys=True,
+                      separators=(',', ': '))
+
+
+def wrap_and_call(prefix, mocks, func, *args, **kwargs):
+    """
+    call func(args, **kwargs) with mocks applied, then unapplies mocks
+    nicer to read than repeating dectorators on each function
+
+    prefix: prefix for mock names (e.g. 'cloudinit.stages.util') or None
+    mocks: dictionary of names (under 'prefix') to mock and either
+        a return value or a dictionary to pass to the mock.patch call
+    func: function to call with mocks applied
+    *args,**kwargs: arguments for 'func'
+
+    return_value: return from 'func'
+    """
+    delim = '.'
+    if prefix is None:
+        prefix = ''
+    prefix = prefix.rstrip(delim)
+    unwraps = []
+    for fname, kw in mocks.items():
+        if prefix:
+            fname = delim.join((prefix, fname))
+        if not isinstance(kw, dict):
+            kw = {'return_value': kw}
+        p = mock.patch(fname, **kw)
+        p.start()
+        unwraps.append(p)
+    try:
+        return func(*args, **kwargs)
+    finally:
+        for p in unwraps:
+            p.stop()
+
+
+try:
+    skipIf = unittest.skipIf
+except AttributeError:
+    # Python 2.6.  Doesn't have to be high fidelity.
+    def skipIf(condition, reason):
+        def decorator(func):
+            def wrapper(*args, **kws):
+                if condition:
+                    return func(*args, **kws)
+                else:
+                    print(reason, file=sys.stderr)
+            return wrapper
+        return decorator
+
+
+# older versions of mock do not have the useful 'assert_not_called'
+if not hasattr(mock.Mock, 'assert_not_called'):
+    def __mock_assert_not_called(mmock):
+        if mmock.call_count != 0:
+            msg = ("[citest] Expected '%s' to not have been called. "
+                   "Called %s times." %
+                   (mmock._mock_name or 'mock', mmock.call_count))
+            raise AssertionError(msg)
+    mock.Mock.assert_not_called = __mock_assert_not_called
+
+
+# vi: ts=4 expandtab