Python CachingFilePath.listdir方法代码示例

# 需要导入模块: from twext.python.filepath import CachingFilePath [as 别名]
# 或者: from twext.python.filepath.CachingFilePath import listdir [as 别名]

#.........这里部分代码省略.........
        """
        Register a child with the given name with this resource.
        @param name: the name of the child (a URI path segment)
        @param child: the child to register
        """
        self.putChildren[name] = child

    def getChild(self, name):
        """
        Look up a child resource.
        @return: the child of this resource with the given name.
        """
        if name == "":
            return self

        child = self.putChildren.get(name, None)
        if child: return child

        child_fp = self.fp.child(name)
        if hasattr(self, "knownChildren"):
            if name in self.knownChildren:
                child_fp.existsCached = True
        if child_fp.exists():
            return self.createSimilarFile(child_fp)
        else:
            return None

    def listChildren(self):
        """
        @return: a sequence of the names of all known children of this resource.
        """
        children = self.putChildren.keys()
        if self.fp.isdir():
            children += [c for c in self.fp.listdir() if c not in children]
            self.knownChildren = set(children)
        return children

    def locateChild(self, req, segments):
        """
        See L{IResource}C{.locateChild}.
        """
        # If getChild() finds a child resource, return it
        child = self.getChild(segments[0])
        if child is not None: return (child, segments[1:])

        # If we're not backed by a directory, we have no children.
        # But check for existance first; we might be a collection resource
        # that the request wants created.
        self.fp.restat(False)
        if self.fp.exists() and not self.fp.isdir(): return (None, ())

        # OK, we need to return a child corresponding to the first segment
        path = segments[0]

        if path:
            fpath = self.fp.child(path)
        else:
            # Request is for a directory (collection) resource
            return (self, server.StopTraversal)

        # Don't run processors on directories - if someone wants their own
        # customized directory rendering, subclass File instead.
        if fpath.isfile():
            processor = self.processors.get(fpath.splitext()[1].lower())
            if processor:
                return (

# 需要导入模块: from twext.python.filepath import CachingFilePath [as 别名]
# 或者: from twext.python.filepath.CachingFilePath import listdir [as 别名]
class EINVALTestCase(TestCase):
    """
    Sometimes, L{os.listdir} will raise C{EINVAL}.  This is a transient error,
    and L{CachingFilePath.listdir} should work around it by retrying the
    C{listdir} operation until it succeeds.
    """

    def setUp(self):
        """
        Create a L{CachingFilePath} for the test to use.
        """
        self.cfp = CachingFilePath(self.mktemp())
        self.clock = Clock()
        self.cfp._sleep = self.clock.advance


    def test_testValidity(self):
        """
        If C{listdir} is replaced on a L{CachingFilePath}, we should be able to
        observe exceptions raised by the replacement.  This verifies that the
        test patching done here is actually testing something.
        """
        class CustomException(Exception): "Just for testing."
        def blowUp(dirname):
            raise CustomException()
        self.cfp._listdir = blowUp
        self.assertRaises(CustomException, self.cfp.listdir)
        self.assertRaises(CustomException, self.cfp.children)


    def test_retryLoop(self):
        """
        L{CachingFilePath} should catch C{EINVAL} and respond by retrying the
        C{listdir} operation until it succeeds.
        """
        calls = []
        def raiseEINVAL(dirname):
            calls.append(dirname)
            if len(calls) < 5:
                raise OSError(EINVAL, "This should be caught by the test.")
            return ['a', 'b', 'c']
        self.cfp._listdir = raiseEINVAL
        self.assertEquals(self.cfp.listdir(), ['a', 'b', 'c'])
        self.assertEquals(self.cfp.children(), [
                CachingFilePath(pathjoin(self.cfp.path, 'a')),
                CachingFilePath(pathjoin(self.cfp.path, 'b')),
                CachingFilePath(pathjoin(self.cfp.path, 'c')),])


    def requireTimePassed(self, filenames):
        """
        Create a replacement for listdir() which only fires after a certain
        amount of time.
        """
        self.calls = []
        def thunk(dirname):
            now = self.clock.seconds()
            if now < 20.0:
                self.calls.append(now)
                raise OSError(EINVAL, "Not enough time has passed yet.")
            else:
                return filenames
        self.cfp._listdir = thunk


    def assertRequiredTimePassed(self):
        """
        Assert that calls to the simulated time.sleep() installed by
        C{requireTimePassed} have been invoked the required number of times.
        """
        # Waiting should be growing by *2 each time until the additional wait
        # exceeds BACKOFF_MAX (5), at which point we should wait for 5s each
        # time.
        def cumulative(values):
            current = 0.0
            for value in values:
                current += value
                yield current

        self.assertEquals(self.calls,
                          list(cumulative(
                    [0.0, 0.1, 0.2, 0.4, 0.8, 1.6, 3.2, 5.0, 5.0])))


    def test_backoff(self):
        """
        L{CachingFilePath} will wait for an increasing interval up to
        C{BACKOFF_MAX} between calls to listdir().
        """
        self.requireTimePassed(['a', 'b', 'c'])
        self.assertEquals(self.cfp.listdir(), ['a', 'b', 'c'])


    def test_siblingExtensionSearch(self):
        """
        L{FilePath.siblingExtensionSearch} is unfortunately not implemented in
        terms of L{FilePath.listdir}, so we need to verify that it will also
        retry.
        """
        filenames = [self.cfp.basename()+'.a',
#.........这里部分代码省略.........