Python os.F_OK Examples

def __init__(self, dir, file_template=_default_file_template,
                 truncate_slug_length=40,
                 version_locations=None,
                 sourceless=False, output_encoding="utf-8"):
        self.dir = dir
        self.file_template = file_template
        self.version_locations = version_locations
        self.truncate_slug_length = truncate_slug_length or 40
        self.sourceless = sourceless
        self.output_encoding = output_encoding
        self.revision_map = revision.RevisionMap(self._load_revisions)

        if not os.access(dir, os.F_OK):
            raise util.CommandError("Path doesn't exist: %r.  Please use "
                                    "the 'init' command to create a new "
                                    "scripts folder." % dir) 

def write_script(
        scriptdir, rev_id, content, encoding='ascii', sourceless=False):
    old = scriptdir.revision_map.get_revision(rev_id)
    path = old.path

    content = textwrap.dedent(content)
    if encoding:
        content = content.encode(encoding)
    with open(path, 'wb') as fp:
        fp.write(content)
    pyc_path = util.pyc_file_from_path(path)
    if os.access(pyc_path, os.F_OK):
        os.unlink(pyc_path)
    script = Script._from_path(scriptdir, path)
    old = scriptdir.revision_map.get_revision(script.revision)
    if old.down_revision != script.down_revision:
        raise Exception("Can't change down_revision "
                        "on a refresh operation.")
    scriptdir.revision_map.add_revision(script, _replace=True)

    if sourceless:
        make_sourceless(path) 

def read_file(location):
    """Returns the contents of a file or None on error. The error is printed to
    stderr.

    Args:
        location (str): The location of the file to be read.
    """
    location = os.path.expandvars(location)

    if not os.access(location, os.F_OK):
        eprint('Configuration file', location, 'not found')
        return None

    try:
        with open(location, 'r') as file:
            return file.read()
    except PermissionError:
        eprint('Cannot read configuration file', location, '(permission)')
        return None 

def GetCacheDir(session):
    """Returns the path of a usable cache directory."""
    cache_dir = session.GetParameter("cache_dir")
    if cache_dir == None:
        return cache_dir

    cache_dir = os.path.expandvars(cache_dir)

    if not cache_dir:
        raise io_manager.IOManagerError(
            "Local profile cache is not configured - "
            "add a cache_dir parameter to ~/.rekallrc.")

    # Cache dir may be specified relative to the home directory.
    cache_dir = os.path.join(config.GetHomeDir(session), cache_dir)

    if not os.access(cache_dir, os.F_OK | os.R_OK | os.W_OK | os.X_OK):
        try:
            os.makedirs(cache_dir)
        except (IOError, OSError):
            raise io_manager.IOManagerError(
                "Unable to create or access cache directory %s" % cache_dir)

    return cache_dir 

def setTmpDir(self):
        """Set the tmpDir attribute to a reasonnable location for a temporary
        directory"""
        if os.name != 'nt':
            # On unix use /tmp by default
            self.tmpDir = os.environ.get("TMPDIR", "/tmp")
            self.tmpDir = os.environ.get("TMP", self.tmpDir)
        else:
            # On Windows use the current directory
            self.tmpDir = os.environ.get("TMPDIR", "")
            self.tmpDir = os.environ.get("TMP", self.tmpDir)
            self.tmpDir = os.environ.get("TEMP", self.tmpDir)
        if not os.path.isdir(self.tmpDir):
            self.tmpDir = ""
        elif not os.access(self.tmpDir, os.F_OK + os.W_OK):
            self.tmpDir = "" 

def _create_test_db(self, verbosity, autoclobber, keepdb=False):
        test_database_name = self._get_test_db_name()

        if keepdb:
            return test_database_name
        if not self.connection.is_in_memory_db(test_database_name):
            # Erase the old test database
            if verbosity >= 1:
                print("Destroying old test database '%s'..." % self.connection.alias)
            if os.access(test_database_name, os.F_OK):
                if not autoclobber:
                    confirm = input(
                        "Type 'yes' if you would like to try deleting the test "
                        "database '%s', or 'no' to cancel: " % test_database_name
                    )
                if autoclobber or confirm == 'yes':
                    try:
                        os.remove(test_database_name)
                    except Exception as e:
                        sys.stderr.write("Got an error deleting the old test database: %s\n" % e)
                        sys.exit(2)
                else:
                    print("Tests cancelled.")
                    sys.exit(1)
        return test_database_name 

def _popen(command, args):
    import os
    path = os.environ.get("PATH", os.defpath).split(os.pathsep)
    path.extend(('/sbin', '/usr/sbin'))
    for dir in path:
        executable = os.path.join(dir, command)
        if (os.path.exists(executable) and
            os.access(executable, os.F_OK | os.X_OK) and
            not os.path.isdir(executable)):
            break
    else:
        return None
    # LC_ALL to ensure English output, 2>/dev/null to prevent output on
    # stderr (Note: we don't have an example where the words we search for
    # are actually localized, but in theory some system could do so.)
    cmd = 'LC_ALL=C %s %s 2>/dev/null' % (executable, args)
    return os.popen(cmd) 

def check_permissions(self, device_id):
        if not os.access(self.devices[device_id]['path'], os.F_OK | os.R_OK | os.X_OK):
            return False
        if not self.check_file_permissions(self.device_file(device_id, 'alternate_modes')):
            return False
        if not self.check_file_permissions(self.device_file(device_id, 'range')):
            return False
        if not self.check_file_permissions(self.device_file(device_id, 'combine_pedals')):
            return False
        if not self.check_file_permissions(self.device_file(device_id, 'gain')):
            return False
        if not self.check_file_permissions(self.device_file(device_id, 'autocenter')):
            return False
        if not self.check_file_permissions(self.device_file(device_id, 'spring_level')):
            return False
        if not self.check_file_permissions(self.device_file(device_id, 'damper_level')):
            return False
        if not self.check_file_permissions(self.device_file(device_id, 'friction_level')):
            return False
        if not self.check_file_permissions(self.device_file(device_id, 'ffb_leds')):
            return False
        if not self.check_file_permissions(self.device_file(device_id, 'peak_ffb_level')):
            return False
        return True 

def is_storage_device(name):
    """Return True if the given name refers to a root device (e.g.
    "sda", "nvme0n1") as opposed to a logical partition (e.g.  "sda1",
    "nvme0n1p1"). If name is a virtual device (e.g. "loop1", "ram")
    return True.
    """
    # Readapted from iostat source code, see:
    # https://github.com/sysstat/sysstat/blob/
    #     97912938cd476645b267280069e83b1c8dc0e1c7/common.c#L208
    # Some devices may have a slash in their name (e.g. cciss/c0d0...).
    name = name.replace('/', '!')
    including_virtual = True
    if including_virtual:
        path = "/sys/block/%s" % name
    else:
        path = "/sys/block/%s/device" % name
    return os.access(path, os.F_OK) 

def _clone_test_db(self, suffix, verbosity, keepdb=False):
        source_database_name = self.connection.settings_dict['NAME']
        target_database_name = self.get_test_db_clone_settings(suffix)['NAME']
        # Forking automatically makes a copy of an in-memory database.
        if not self.is_in_memory_db(source_database_name):
            # Erase the old test database
            if os.access(target_database_name, os.F_OK):
                if keepdb:
                    return
                if verbosity >= 1:
                    print("Destroying old test database for alias %s..." % (
                        self._get_database_display_str(verbosity, target_database_name),
                    ))
                try:
                    os.remove(target_database_name)
                except Exception as e:
                    sys.stderr.write("Got an error deleting the old test database: %s\n" % e)
                    sys.exit(2)
            try:
                shutil.copy(source_database_name, target_database_name)
            except Exception as e:
                sys.stderr.write("Got an error cloning the test database: %s\n" % e)
                sys.exit(2) 

def get_writable_file(self,existing_only=0):
        """ Return the name of the first writable catalog file.

            Its parent directory must also be writable.  This is so that
            compiled modules can be written to the same directory.
        """
        # note: both file and its parent directory must be writeable
        if existing_only:
            files = self.get_existing_files()
        else:
            files = self.get_catalog_files()
        # filter for (file exists and is writable) OR directory is writable

        def file_test(x):
            from os import access, F_OK, W_OK
            return (access(x,F_OK) and access(x,W_OK) or
                    access(os.path.dirname(x),W_OK))
        writable = filter(file_test,files)
        if writable:
            file = writable[0]
        else:
            file = None
        return file 

def _popen(command, args):
    import os
    path = os.environ.get("PATH", os.defpath).split(os.pathsep)
    path.extend(('/sbin', '/usr/sbin'))
    for dir in path:
        executable = os.path.join(dir, command)
        if (os.path.exists(executable) and
            os.access(executable, os.F_OK | os.X_OK) and
            not os.path.isdir(executable)):
            break
    else:
        return None
    # LC_ALL to ensure English output, 2>/dev/null to prevent output on
    # stderr (Note: we don't have an example where the words we search for
    # are actually localized, but in theory some system could do so.)
    cmd = 'LC_ALL=C %s %s 2>/dev/null' % (executable, args)
    return os.popen(cmd) 

def can_write_dir(path):
  """Determines if the directory at path can be written to by the current process.

  If the directory doesn't exist, determines if it can be created and thus written to.

  N.B.: This is a best-effort check only that uses permission heuristics and does not actually test
  that the directory can be written to with and writes.

  :param str path: The directory path to test.
  :return: `True` if the given path is a directory that can be written to by the current process.
  :rtype boo:
  """
  while not os.access(path, os.F_OK):
    parent_path = os.path.dirname(path)
    if not parent_path or (parent_path == path):
      # We've recursed up to the root without success, which shouldn't happen,
      return False
    path = parent_path
  return os.path.isdir(path) and os.access(path, os.R_OK | os.W_OK | os.X_OK) 

def is_storage_device(name):
    """Return True if the given name refers to a root device (e.g.
    "sda", "nvme0n1") as opposed to a logical partition (e.g.  "sda1",
    "nvme0n1p1"). If name is a virtual device (e.g. "loop1", "ram")
    return True.
    """
    # Readapted from iostat source code, see:
    # https://github.com/sysstat/sysstat/blob/
    #     97912938cd476645b267280069e83b1c8dc0e1c7/common.c#L208
    # Some devices may have a slash in their name (e.g. cciss/c0d0...).
    name = name.replace('/', '!')
    including_virtual = True
    if including_virtual:
        path = "/sys/block/%s" % name
    else:
        path = "/sys/block/%s/device" % name
    return os.access(path, os.F_OK) 

def is_storage_device(name):
    """Return True if the given name refers to a root device (e.g.
    "sda", "nvme0n1") as opposed to a logical partition (e.g.  "sda1",
    "nvme0n1p1"). If name is a virtual device (e.g. "loop1", "ram")
    return True.
    """
    # Readapted from iostat source code, see:
    # https://github.com/sysstat/sysstat/blob/
    #     97912938cd476645b267280069e83b1c8dc0e1c7/common.c#L208
    # Some devices may have a slash in their name (e.g. cciss/c0d0...).
    name = name.replace('/', '!')
    including_virtual = True
    if including_virtual:
        path = "/sys/block/%s" % name
    else:
        path = "/sys/block/%s/device" % name
    return os.access(path, os.F_OK) 

def which(
    command: str, *, return_bool: bool = False, raise_error: bool = False, raise_msg: str = None, env: str = None
) -> Union[bool, None, str]:
    """Test to see if a command is available.

    Returns
    -------
    str or None
        By default, returns command path if command found or `None` if not.
        Environment is $PATH or `os.pathsep`-separated `env`, less any None values.
    bool
        When `return_bool=True`, returns whether or not found.

    Raises
    ------
    ModuleNotFoundError
        When `raises_error=True` and command not found. Raises generic message plus any `raise_msg`.

    """
    if env is None:
        lenv = {"PATH": os.pathsep + os.environ.get("PATH", "") + os.path.dirname(sys.executable)}
    else:
        lenv = {"PATH": os.pathsep.join([os.path.abspath(x) for x in env.split(os.pathsep) if x != ""])}
    lenv = {k: v for k, v in lenv.items() if v is not None}

    ans = shutil.which(command, mode=os.F_OK | os.X_OK, path=lenv["PATH"])

    if raise_error and ans is None:
        raise ModuleNotFoundError(
            f"Command '{command}' not found in envvar PATH.{' ' + raise_msg if raise_msg else ''}"
        )

    if return_bool:
        return bool(ans)
    else:
        return ans 

def _clean_check(cmd, target):
    """
    Run the command to download target.

    If the command fails, clean up before re-raising the error.
    """
    try:
        subprocess.check_call(cmd)
    except subprocess.CalledProcessError:
        if os.access(target, os.F_OK):
            os.unlink(target)
        raise 

def _clean_check(cmd, target):
    """
    Run the command to download target.

    If the command fails, clean up before re-raising the error.
    """
    try:
        subprocess.check_call(cmd)
    except subprocess.CalledProcessError:
        if os.access(target, os.F_OK):
            os.unlink(target)
        raise 

def _clean_check(cmd, target):
    """
    Run the command to download target. If the command fails, clean up before
    re-raising the error.
    """
    try:
        subprocess.check_call(cmd)
    except subprocess.CalledProcessError:
        if os.access(target, os.F_OK):
            os.unlink(target)
        raise 

def _clean_check(cmd, target):
    """
    Run the command to download target.

    If the command fails, clean up before re-raising the error.
    """
    try:
        subprocess.check_call(cmd)
    except subprocess.CalledProcessError:
        if os.access(target, os.F_OK):
            os.unlink(target)
        raise 

def __init__(self, path=None,
                 num_works=1,
                 splitting="TVT",
                 one_hot=False,
                 name="create_inputs"):
        """
        Args:
            path: Path to store data.
            name: Name for the operations.
        """

        # path exists and is writable?
        if path is None:
            path = os.path.join(os.environ["HOME"], ".cache", "capslayer", "datasets", "fashion_mnist")
            os.makedirs(path, exist_ok=True)
        elif os.access(path, os.F_OK):
            path = path if os.path.basename(path) == "fashion_mnist" else os.path.join(path, "fashion_mnist")
            os.makedirs(path, exist_ok=True)
        elif os.access(path, os.W_OK):
            raise IOError("Permission denied! Path %s is not writable." % (str(path)))

        # data downloaded and data extracted?
        maybe_download_and_extract("fashion-mnist", path)
        # data tfrecorded?
        tfrecord_runner(path, force=False)
        self.handle = tf.placeholder(tf.string, shape=[])
        self.next_element = None
        self.path = path
        self.name = name 

def __init__(self, path=None,
                 num_works=1,
                 splitting="TVT",
                 one_hot=False,
                 name="create_inputs"):
        """
        Args:
            path: Path to store data.
            name: Name for the operations.
        """

        # path exists and is writable?
        if path is None:
            path = os.path.join(os.environ["HOME"], ".cache", "capslayer", "datasets", "mnist")
            os.makedirs(path, exist_ok=True)
        elif os.access(path, os.F_OK):
            path = path if os.path.basename(path) == "mnist" else os.path.join(path, "mnist")
            os.makedirs(path, exist_ok=True)
        elif os.access(path, os.W_OK):
            raise IOError("Permission denied! Path %s is not writable." % (str(path)))

        # data downloaded and data extracted?
        maybe_download_and_extract("mnist", path)
        # data tfrecorded?
        tfrecord_runner(path, force=False)
        self.handle = tf.placeholder(tf.string, shape=[])
        self.next_element = None
        self.path = path
        self.name = name 

def setUp(self):
    """Configure test harness."""
    # Configure os.environ to make it look like the relevant parts of the
    # CGI environment that the stub relies on.
    self.original_environ = dict(os.environ)
    os.environ.update({
        'APPLICATION_ID': 'app',
        'SERVER_NAME': 'localhost',
        'SERVER_PORT': '8080',
        'AUTH_DOMAIN': 'abcxyz.com',
        'USER_EMAIL': 'user@abcxyz.com',
        })

    # Set up mox.
    self.mox = mox.Mox()

    # Use a fresh file datastore stub.
    self.tmpdir = tempfile.mkdtemp()
    self.datastore_file = os.path.join(self.tmpdir, 'datastore_v3')
    self.history_file = os.path.join(self.tmpdir, 'history')
    for filename in [self.datastore_file, self.history_file]:
      if os.access(filename, os.F_OK):
        os.remove(filename)

    self.stub = datastore_file_stub.DatastoreFileStub(
        'app', self.datastore_file, self.history_file, use_atexit=False)

    self.apiproxy = apiproxy_stub_map.APIProxyStubMap()
    apiproxy_stub_map.apiproxy = self.apiproxy
    apiproxy_stub_map.apiproxy.RegisterStub('datastore_v3', self.stub) 

def setUp(self):
    """Configure test harness."""
    # Configure os.environ to make it look like the relevant parts of the
    # CGI environment that the stub relies on.
    self.original_environ = dict(os.environ)
    os.environ.update({
        'APPLICATION_ID': 'app',
        'SERVER_NAME': 'localhost',
        'SERVER_PORT': '8080',
        'AUTH_DOMAIN': 'abcxyz.com',
        'USER_EMAIL': 'user@abcxyz.com',
        })

    # Set up testing blobstore files.
    self.tmpdir = tempfile.mkdtemp()
    storage_directory = os.path.join(self.tmpdir, 'blob_storage')
    self.blob_storage = file_blob_storage.FileBlobStorage(storage_directory,
                                                          'appid1')
    self.blobstore_stub = blobstore_stub.BlobstoreServiceStub(self.blob_storage)

    # Use a fresh file datastore stub.
    self.datastore_file = os.path.join(self.tmpdir, 'datastore_v3')
    self.history_file = os.path.join(self.tmpdir, 'history')
    for filename in [self.datastore_file, self.history_file]:
      if os.access(filename, os.F_OK):
        os.remove(filename)

    self.datastore_stub = datastore_file_stub.DatastoreFileStub(
        'app', self.datastore_file, self.history_file, use_atexit=False)

    self.apiproxy = apiproxy_stub_map.APIProxyStubMap()
    apiproxy_stub_map.apiproxy = self.apiproxy
    apiproxy_stub_map.apiproxy.RegisterStub('datastore_v3', self.datastore_stub)
    apiproxy_stub_map.apiproxy.RegisterStub('blobstore', self.blobstore_stub) 

def _clean_check(cmd, target):
    """
    Run the command to download target. If the command fails, clean up before
    re-raising the error.
    """
    try:
        subprocess.check_call(cmd)
    except subprocess.CalledProcessError:
        if os.access(target, os.F_OK):
            os.unlink(target)
        raise 

def init(config, directory, template='generic'):
    """Initialize a new scripts directory."""

    if os.access(directory, os.F_OK):
        raise util.CommandError("Directory %s already exists" % directory)

    template_dir = os.path.join(config.get_template_directory(),
                                template)
    if not os.access(template_dir, os.F_OK):
        raise util.CommandError("No such template %r" % template)

    util.status("Creating directory %s" % os.path.abspath(directory),
                os.makedirs, directory)

    versions = os.path.join(directory, 'versions')
    util.status("Creating directory %s" % os.path.abspath(versions),
                os.makedirs, versions)

    script = ScriptDirectory(directory)

    for file_ in os.listdir(template_dir):
        file_path = os.path.join(template_dir, file_)
        if file_ == 'alembic.ini.mako':
            config_file = os.path.abspath(config.config_file_name)
            if os.access(config_file, os.F_OK):
                util.msg("File %s already exists, skipping" % config_file)
            else:
                script._generate_template(
                    file_path,
                    config_file,
                    script_location=directory
                )
        elif os.path.isfile(file_path):
            output_file = os.path.join(directory, file_)
            script._copy_file(
                file_path,
                output_file
            )

    util.msg("Please edit configuration/connection/logging "
             "settings in %r before proceeding." % config_file) 

def env_file_fixture(txt):
    dir_ = os.path.join(_get_staging_directory(), 'scripts')
    txt = """
from alembic import context

config = context.config
""" + txt

    path = os.path.join(dir_, "env.py")
    pyc_path = util.pyc_file_from_path(path)
    if os.access(pyc_path, os.F_OK):
        os.unlink(pyc_path)

    with open(path, 'w') as f:
        f.write(txt) 

def _testing_config():
    from alembic.config import Config
    if not os.access(_get_staging_directory(), os.F_OK):
        os.mkdir(_get_staging_directory())
    return Config(os.path.join(_get_staging_directory(), 'test_alembic.ini')) 

def _clean_check(cmd, target):
    """
    Run the command to download target. If the command fails, clean up before
    re-raising the error.
    """
    try:
        subprocess.check_call(cmd)
    except subprocess.CalledProcessError:
        if os.access(target, os.F_OK):
            os.unlink(target)
        raise 

def test_write_default_config():
    """Write config file."""
    name = __name__ + '1'
    assert chromaterm.default_config.write_default_config('.', name)
    assert os.access(os.path.join('.', name), os.F_OK)
    os.remove(__name__ + '1')