python3-autopilot 1.5.1+16.04.20160412-0ubuntu1 / usr / lib / python3 / dist-packages / autopilot / introspection / types.py

# -*- Mode: Python; coding: utf-8; indent-tabs-mode: nil; tab-width: 4 -*-
#
# Autopilot Functional Test Tool
# Copyright (C) 2013 Canonical
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.
#


"""
Autopilot proxy type support.
=============================

This module defines the classes that are used for all attributes on proxy
objects. All proxy objects contain attributes that transparently mirror the
values present in the application under test. Autopilot takes care of keeping
these values up to date.

Object attributes fall into two categories. Attributes that are a single
string, boolean, or integer property are sent directly across DBus. These are
called "plain" types, and are stored in autopilot as instnaces of the
:class:`PlainType` class. Attributes that are more complex (a rectangle, for
example) are called "complex" types, and are split into several component
values, sent across dbus, and are then reconstituted in autopilot into useful
objects.

"""

import pytz
from datetime import datetime, time, timedelta
from dateutil.tz import gettz

import dbus
import logging
from testtools.matchers import Equals

from autopilot.introspection.utilities import translate_state_keys
from autopilot.utilities import sleep, compatible_repr


_logger = logging.getLogger(__name__)


class ValueType(object):

    """Store constants for different special types that autopilot understands.

    DO NOT add items here unless you have documented them correctly in
    docs/appendix/protocol.rst.

    """
    PLAIN = 0
    RECTANGLE = 1
    POINT = 2
    SIZE = 3
    COLOR = 4
    DATETIME = 5
    TIME = 6
    POINT3D = 7
    UNKNOWN = -1


def create_value_instance(value, parent, name):
    """Create an object that exposes the interesing part of the value
    specified, given the value_type_id.

    :param parent: The object this attribute belongs to.
    :param name: The name of this attribute.
    :param value: The value array from DBus.

    """
    type_dict = {
        ValueType.PLAIN: _make_plain_type,
        ValueType.RECTANGLE: Rectangle,
        ValueType.COLOR: Color,
        ValueType.POINT: Point,
        ValueType.SIZE: Size,
        ValueType.DATETIME: DateTime,
        ValueType.TIME: Time,
        ValueType.POINT3D: Point3D,
        ValueType.UNKNOWN: _make_plain_type,
    }
    type_id = value[0]
    value = value[1:]

    if type_id not in type_dict:
        _logger.warning("Unknown type id %d", type_id)
        type_id = ValueType.UNKNOWN

    type_class = type_dict.get(type_id, None)
    if type_id == ValueType.UNKNOWN:
        value = [dbus.Array(value)]
    if len(value) == 0:
        raise ValueError("Cannot create attribute, no data supplied")
    return type_class(*value, parent=parent, name=name)


class TypeBase(object):

    def wait_for(self, expected_value, timeout=10):
        """Wait up to 10 seconds for our value to change to
        *expected_value*.

        *expected_value* can be a testtools.matcher. Matcher subclass (like
        LessThan, for example), or an ordinary value.

        This works by refreshing the value using repeated dbus calls.

        :raises AssertionError: if the attribute was not equal to the
         expected value after 10 seconds.

        :raises RuntimeError: if the attribute you called this on was not
         constructed as part of an object.

        """
        # It's guaranteed that our value is up to date, since __getattr__
        # calls refresh_state. This if statement stops us waiting if the
        # value is already what we expect:
        if self == expected_value:
            return

        if self.name is None or self.parent is None:
            raise RuntimeError(
                "This variable was not constructed as part of "
                "an object. The wait_for method cannot be used."
            )

        def make_unicode(value):
            if isinstance(value, bytes):
                return value.decode('utf8')
            return value

        if hasattr(expected_value, 'expected'):
            expected_value.expected = make_unicode(expected_value.expected)

        # unfortunately not all testtools matchers derive from the Matcher
        # class, so we can't use issubclass, isinstance for this:
        match_fun = getattr(expected_value, 'match', None)
        is_matcher = match_fun and callable(match_fun)
        if not is_matcher:
            expected_value = Equals(expected_value)

        time_left = timeout
        while True:
            # TODO: These next three lines are duplicated from the parent...
            # can we just have this code once somewhere?
            _, new_state = self.parent._get_new_state()
            new_state = translate_state_keys(new_state)
            new_value = new_state[self.name][1:]
            if len(new_value) == 1:
                new_value = make_unicode(new_value[0])
            # Support for testtools.matcher classes:
            mismatch = expected_value.match(new_value)
            if mismatch:
                failure_msg = mismatch.describe()
            else:
                self.parent._set_properties(new_state)
                return

            if time_left >= 1:
                sleep(1)
                time_left -= 1
            else:
                sleep(time_left)
                break

        raise AssertionError(
            "After %.1f seconds test on %s.%s failed: %s" % (
                timeout, self.parent.__class__.__name__, self.name,
                failure_msg))


class PlainType(TypeBase):

    """Plain type support in autopilot proxy objects.

    Instances of this class will be used for all plain attrubites. The word
    "plain" in this context means anything that's marshalled as a string,
    boolean or integer type across dbus.

    Instances of these classes can be used just like the underlying type. For
    example, given an object property called 'length' that is marshalled over
    dbus as an integer value, the following will be true::

        >>> isinstance(object.length, PlainType)
        True
        >>> isinstance(object.length, int)
        True
        >>> print(object.length)
        123
        >>> print(object.length + 32)
        155

    However, a special case exists for boolean values: because you cannot
    subclass from the 'bool' type, the following check will fail (
    ``object.visible`` is a boolean property)::

        >>> isinstance(object.visible, bool)
        False

    However boolean values will behave exactly as you expect them to.

    """

    def __new__(cls, value, parent=None, name=None):
        return _make_plain_type(value, parent=parent, name=name)


def _get_repr_callable_for_value_class(cls):
    repr_map = {
        dbus.Byte: _integer_repr,
        dbus.Int16: _integer_repr,
        dbus.Int32: _integer_repr,
        dbus.UInt16: _integer_repr,
        dbus.UInt32: _integer_repr,
        dbus.Int64: _integer_repr,
        dbus.UInt64: _integer_repr,
        dbus.String: _text_repr,
        dbus.ObjectPath: _text_repr,
        dbus.Signature: _text_repr,
        dbus.ByteArray: _bytes_repr,
        dbus.Boolean: _boolean_repr,
        dbus.Dictionary: _dict_repr,
        dbus.Double: _float_repr,
        dbus.Struct: _tuple_repr,
        dbus.Array: _list_repr,
    }
    return repr_map.get(cls, None)


def _get_str_callable_for_value_class(cls):
    str_map = {
        dbus.Boolean: _boolean_str,
        dbus.Byte: _integer_str,
    }
    return str_map.get(cls, None)


@compatible_repr
def _integer_repr(self):
    return str(int(self))


def _create_generic_repr(target_type):
    return compatible_repr(lambda self: repr(target_type(self)))

_bytes_repr = _create_generic_repr(bytes)
_text_repr = _create_generic_repr(str)
_dict_repr = _create_generic_repr(dict)
_list_repr = _create_generic_repr(list)
_tuple_repr = _create_generic_repr(tuple)
_float_repr = _create_generic_repr(float)
_boolean_repr = _create_generic_repr(bool)


def _create_generic_str(target_type):
    return compatible_repr(lambda self: str(target_type(self)))


_boolean_str = _create_generic_str(bool)
_integer_str = _integer_repr


def _make_plain_type(value, parent=None, name=None):
    new_type = _get_plain_type_class(type(value), parent, name)
    return new_type(value)


# Thomi 2014-03-27: dbus types are immutable, which means that we cannot set
# parent and name on the instances we create. This means we have to set them
# as type attributes, which means that this cache doesn't speed things up that
# much. Ideally we'd not rely on the dbus types at all, and simply transform
# them into our own types, but that's work for a separate branch.
#
# Further to the above, we cannot cache these results, since the hash for
# the parent parameter is almost always the same, leading to incorrect cache
# hits. We really need to implement our own types here I think.
def _get_plain_type_class(value_class, parent, name):
    new_type_name = value_class.__name__
    new_type_bases = (value_class, PlainType)
    new_type_dict = dict(parent=parent, name=name)
    repr_callable = _get_repr_callable_for_value_class(value_class)
    if repr_callable:
        new_type_dict['__repr__'] = repr_callable
    str_callable = _get_str_callable_for_value_class(value_class)
    if str_callable:
        new_type_dict['__str__'] = str_callable
    return type(new_type_name, new_type_bases, new_type_dict)


def _array_packed_type(num_args):
    """Return a base class that accepts 'num_args' and is packed into a dbus
    Array type.

    """
    class _ArrayPackedType(dbus.Array, TypeBase):

        def __init__(self, *args, **kwargs):
            if len(args) != self._required_arg_count:
                raise ValueError(
                    "%s must be constructed with %d arguments, not %d"
                    % (
                        self.__class__.__name__,
                        self._required_arg_count,
                        len(args)
                    )
                )
            super(_ArrayPackedType, self).__init__(args)
            # TODO: pop instead of get, and raise on unknown kwarg
            self.parent = kwargs.get("parent", None)
            self.name = kwargs.get("name", None)
    return type(
        "_ArrayPackedType_{}".format(num_args),
        (_ArrayPackedType,),
        dict(_required_arg_count=num_args)
    )


class Rectangle(_array_packed_type(4)):

    """The RectangleType class represents a rectangle in cartesian space.

    To construct a rectangle, pass the x, y, width and height parameters in to
    the class constructor::

        my_rect = Rectangle(12,13,100,150)

    These attributes can be accessed either using named attributes, or via
    sequence indexes::

        >>>my_rect = Rectangle(12,13,100,150)
        >>> my_rect.x == my_rect[0] == 12
        True
        >>> my_rect.y == my_rect[1] == 13
        True
        >>> my_rect.w == my_rect[2] == 100
        True
        >>> my_rect.h == my_rect[3] == 150
        True

    You may also access the width and height values using the ``width`` and
    ``height`` properties::

        >>> my_rect.width == my_rect.w
        True
        >>> my_rect.height == my_rect.h
        True

    Rectangles can be compared using ``==`` and ``!=``, either to another
    Rectangle instance, or to any mutable sequence type::

        >>> my_rect == [12, 13, 100, 150]
        True
        >>> my_rect != Rectangle(1,2,3,4)
        True

    """

    @property
    def x(self):
        return self[0]

    @property
    def y(self):
        return self[1]

    @property
    def w(self):
        return self[2]

    @property
    def width(self):
        return self[2]

    @property
    def h(self):
        return self[3]

    @property
    def height(self):
        return self[3]

    @compatible_repr
    def __repr__(self):
        coords = ', '.join((str(c) for c in self))
        return 'Rectangle(%s)' % (coords)


class Point(_array_packed_type(2)):

    """The Point class represents a 2D point in cartesian space.

    To construct a Point, pass in the x, y parameters to the class
    constructor::

        >>> my_point = Point(50,100)

    These attributes can be accessed either using named attributes, or via
    sequence indexes::

        >>> my_point.x == my_point[0] == 50
        True
        >>> my_point.y == my_point[1] == 100
        True

    Point instances can be compared using ``==`` and ``!=``, either to another
    Point instance, or to any mutable sequence type with the correct number of
    items::

        >>> my_point == [50, 100]
        True
        >>> my_point != Point(5, 10)
        True

    """

    @property
    def x(self):
        return self[0]

    @property
    def y(self):
        return self[1]

    @compatible_repr
    def __repr__(self):
        return 'Point(%d, %d)' % (self.x, self.y)


class Size(_array_packed_type(2)):

    """The Size class represents a 2D size in cartesian space.

    To construct a Size, pass in the width, height parameters to the class
    constructor::

        >>> my_size = Size(50,100)

    These attributes can be accessed either using named attributes, or via
    sequence indexes::

        >>> my_size.width == my_size.w == my_size[0] == 50
        True
        >>> my_size.height == my_size.h == my_size[1] == 100
        True

    Size instances can be compared using ``==`` and ``!=``, either to another
    Size instance, or to any mutable sequence type with the correct number of
    items::

        >>> my_size == [50, 100]
        True
        >>> my_size != Size(5, 10)
        True

    """

    @property
    def w(self):
        return self[0]

    @property
    def width(self):
        return self[0]

    @property
    def h(self):
        return self[1]

    @property
    def height(self):
        return self[1]

    @compatible_repr
    def __repr__(self):
        return 'Size(%d, %d)' % (self.w, self.h)


class Color(_array_packed_type(4)):

    """The Color class represents an RGBA Color.

    To construct a Color, pass in the red, green, blue and alpha parameters to
    the class constructor::

        >>> my_color = Color(50, 100, 200, 255)

    These attributes can be accessed either using named attributes, or via
    sequence indexes::

        >>> my_color.red == my_color[0] == 50
        True
        >>> my_color.green == my_color[1] == 100
        True
        >>> my_color.blue == my_color[2] == 200
        True
        >>> my_color.alpha == my_color[3] == 255
        True

    Color instances can be compared using ``==`` and ``!=``, either to another
    Color instance, or to any mutable sequence type with the correct number of
    items::

        >>> my_color == [50, 100, 200, 255]
        True
        >>> my_color != Color(5, 10, 0, 0)
        True

    """

    @property
    def red(self):
        return self[0]

    @property
    def green(self):
        return self[1]

    @property
    def blue(self):
        return self[2]

    @property
    def alpha(self):
        return self[3]

    @compatible_repr
    def __repr__(self):
        return 'Color(%d, %d, %d, %d)' % (
            self.red,
            self.green,
            self.blue,
            self.alpha
        )


class DateTime(_array_packed_type(1)):

    """The DateTime class represents a date and time in the UTC timezone.

    DateTime is constructed by passing a unix timestamp in to the constructor.
    The incoming timestamp is assumed to be in UTC.

    .. note:: This class expects the passed in timestamp to be in UTC but will
      display the resulting date and time in local time (using the local
      timezone).

      This is done to mimic the behaviour of most applications which will
      display date and time in local time by default

    Timestamps are expressed as the number of seconds since 1970-01-01T00:00:00
    in the UTC timezone::

        >>> my_dt = DateTime(1377209927)

    This timestamp can always be accessed either using index access or via a
    named property::

        >>> my_dt[0] == my_dt.timestamp == 1377209927
        True

    DateTime objects also expose the usual named properties you would expect on
    a date/time object::

        >>> my_dt.year
        2013
        >>> my_dt.month
        8
        >>> my_dt.day
        22
        >>> my_dt.hour
        22
        >>> my_dt.minute
        18
        >>> my_dt.second
        47

    Two DateTime objects can be compared for equality::

        >>> my_dt == DateTime(1377209927)
        True

    You can also compare a DateTime with any mutable sequence type containing
    the timestamp (although this probably isn't very useful for test authors)::

        >>> my_dt == [1377209927]
        True

    Finally, you can also compare a DateTime instance with a python datetime
    instance::

        >>> my_datetime = datetime.datetime.utcfromtimestamp(1377209927)
        True


    .. note:: Autopilot supports dates beyond 2038 on 32-bit platforms. To
     achieve this the underlying mechanisms require to work with timezone aware
     datetime objects.

      This means that the following won't always be true (due to the naive
      timestamp not having the correct daylight-savings time details)::

        >>> # This time stamp is within DST in the 'Europe/London' timezone
        >>> dst_ts = 1405382400
        >>> os.environ['TZ'] ='Europe/London'
        >>> time.tzset()
        >>> datetime.fromtimestamp(dst_ts).hour == DateTime(dst_ts).hour
        False

      But this will work::

        >>> from dateutil.tz import gettz
        >>> datetime.fromtimestamp(
                dst_ts, gettz()).hour == DateTime(dst_ts).hour
        True

      And this will always work to::

        >>> dt1 =  DateTime(nz_dst_timestamp)
        >>> dt2 = datetime(
                dt1.year, dt1.month, dt1.day, dt1.hour, dt1.minute, dt1.second
            )
        >>> dt1 == dt2
        True

    .. note:: DateTime.timestamp() will not always equal the passed in
      timestamp.
      To paraphrase a message from [http://bugs.python.org/msg229393]
      "datetime.timestamp is supposed to be inverse of
      datetime.fromtimestamp(), but since the later is not monotonic, no such
      inverse exists in the strict mathematical sense."

    DateTime instances can be converted to datetime instances::

        >>> isinstance(my_dt.datetime, datetime.datetime)
        True

    """
    def __init__(self, *args, **kwargs):
        super(DateTime, self).__init__(*args, **kwargs)
        # Using timedelta in this manner is a workaround so that we can support
        # timestamps larger than the 32bit time_t limit on 32bit hardware.
        # We then apply the timezone information to this to get the correct
        # datetime.
        #
        # Note. self[0] is a UTC timestamp
        utc = pytz.timezone('UTC')
        EPOCH = datetime(1970, 1, 1, tzinfo=utc)
        utc_dt = EPOCH + timedelta(seconds=self[0])

        self._cached_dt = utc_dt.astimezone(gettz())

    @property
    def year(self):
        return self._cached_dt.year

    @property
    def month(self):
        return self._cached_dt.month

    @property
    def day(self):
        return self._cached_dt.day

    @property
    def hour(self):
        return self._cached_dt.hour

    @property
    def minute(self):
        return self._cached_dt.minute

    @property
    def second(self):
        return self._cached_dt.second

    @property
    def timestamp(self):
        return self._cached_dt.timestamp()

    @property
    def datetime(self):
        return self._cached_dt

    def __eq__(self, other):
        # A little 'magic' here, if the datetime object to test against is
        # naive, use the tzinfo from the cached datetime (just for the
        # comparison)
        if isinstance(other, datetime):
            if other.tzinfo is None:
                return other.replace(
                    tzinfo=self._cached_dt.tzinfo
                ) == self._cached_dt
            return other == self._cached_dt
        return super(DateTime, self).__eq__(other)

    @compatible_repr
    def __repr__(self):
        return 'DateTime(%d-%02d-%02d %02d:%02d:%02d)' % (
            self.year,
            self.month,
            self.day,
            self.hour,
            self.minute,
            self.second
        )


class Time(_array_packed_type(4)):

    """The Time class represents a time, without a date component.

    You can construct a Time instnace by passing the hours, minutes, seconds,
    and milliseconds to the class constructor::

        >>> my_time = Time(12, 34, 01, 23)

    The values passed in must be valid for their positions (ie..- 0-23 for
    hours, 0-59 for minutes and seconds, and 0-999 for milliseconds). Passing
    invalid values will cause a ValueError to be raised.

    The hours, minutes, seconds, and milliseconds can be accessed using either
    index access or named properties::

        >>> my_time.hours == my_time[0] == 12
        True
        >>> my_time.minutes == my_time[1] == 34
        True
        >>> my_time.seconds == my_time[2] == 01
        True
        >>> my_time.milliseconds == my_time[3] == 23
        True

    Time instances can be compared to other time instances, any mutable
    sequence containing four integers, or datetime.time instances::

        >>> my_time == Time(12, 34, 01, 23)
        True
        >>> my_time == Time(1,2,3,4)
        False

        >>> my_time == [12, 34, 01, 23]
        True

        >>> my_time == datetime.time(12, 34, 01, 23000)
        True

    Note that the Time class stores milliseconds, while the ``datettime.time``
    class stores microseconds.

    Finally, you can get a ``datetime.time`` instance from a Time instance::

        >>> isinstance(my_time.time, datetime.time)
        True

    """

    def __init__(self, *args, **kwargs):
        super(Time, self).__init__(*args, **kwargs)
        # datetime.time uses microseconds, instead of mulliseconds:
        self._cached_time = time(self[0], self[1], self[2], self[3] * 1000)

    @property
    def hour(self):
        return self._cached_time.hour

    @property
    def minute(self):
        return self._cached_time.minute

    @property
    def second(self):
        return self._cached_time.second

    @property
    def millisecond(self):
        return self._cached_time.microsecond / 1000

    @property
    def time(self):
        return self._cached_time

    def __eq__(self, other):
        if isinstance(other, time):
            return other == self._cached_time
        return super(Time, self).__eq__(other)

    @compatible_repr
    def __repr__(self):
        return 'Time(%02d:%02d:%02d.%03d)' % (
            self.hour,
            self.minute,
            self.second,
            self.millisecond
        )


class Point3D(_array_packed_type(3)):

    """The Point3D class represents a 3D point in cartesian space.

    To construct a Point3D, pass in the x, y and z parameters to the class
    constructor::

        >>> my_point = Point(50,100,20)

    These attributes can be accessed either using named attributes, or via
    sequence indexes::

        >>> my_point.x == my_point[0] == 50
        True
        >>> my_point.y == my_point[1] == 100
        True
        >>> my_point.z == my_point[2] == 20
        True

    Point3D instances can be compared using ``==`` and ``!=``, either to
    another Point3D instance, or to any mutable sequence type with the correct
    number of items::

        >>> my_point == [50, 100, 20]
        True
        >>> my_point != Point(5, 10, 2)
        True

    """

    @property
    def x(self):
        return self[0]

    @property
    def y(self):
        return self[1]

    @property
    def z(self):
        return self[2]

    @compatible_repr
    def __repr__(self):
        return 'Point3D(%d, %d, %d)' % (
            self.x,
            self.y,
            self.z,
        )