class DisplayDriver(object):
"""
This class represents the display driver that links the raspberry pi to the display. This driver will have high-
level control over the data being sent to the display, but will do this mostly through the help of smaller utility
classes.
"""
logger = logging.getLogger("display")
def __init__(self):
"""
Ctor - Initialises the display driver, setting up the database helper and display controller.
"""
self._db_helper = DatabaseHelper(db_name)
self._display_controller = DisplayController(serial_name, serial_baudrate)
def start(self):
"""
Starts the application: begins checking the current time and working out what information needs to be sent
to the display at that time.
"""
mode = ScreensaverMode(self._db_helper.get_random_screensaver())
last_pattern = None
last_check_time = datetime.datetime.now() - datetime.timedelta(minutes=10)
while True:
# Check the current time and make it accurate to the second
current_time = datetime.datetime.now()
min_current_time = minutify(current_time)
if (current_time.minute % 5) == 0 and (min_current_time > last_check_time):
# If the current time is on one of the five min. intervals, attempt to pull a pattern from the
# internal database.
last_check_time = min_current_time
t_format = "%Y-%m-%d %H:%M:00.000000"
pattern = self._db_helper.get_run_for_time(current_time.strftime(t_format))
if pattern:
# If a pattern is successfully pulled, run the display's 'run mode' on it.
mode = RunMode(pattern)
else:
# Otherwise pull a random screensaver from the internal database and run that in 'screensaver
# mode'
mode = ScreensaverMode(self._db_helper.get_random_screensaver(), last_pattern)
if not mode.is_active():
# If the current pattern finishes before the five minute timer has stopped, switch to
# screensaver mode
mode = ScreensaverMode(self._db_helper.get_random_screensaver(), last_pattern)
# Retrieve the latest pattern to be sent to the display
last_pattern = mode.get_display_pattern()
# Send the pattern to the display controller for printing.
self._display_controller.output_pattern(last_pattern)
# While not working, sleep
sleep_until_time = current_time + datetime.timedelta(seconds=sleep_time)
time.sleep((sleep_until_time - datetime.datetime.now()).microseconds / 1000000)
self.logger.warn("Outputted pattern at: %s" % current_time)
def test__draw(self, serial_mock):
"""
Test the private set function of DisplayController
"""
serial = MagicMock()
serial.write = MagicMock()
dc = DisplayController(0, 9600)
dc._connection = serial
dc._draw()
serial.write.assert_called_once_with('3')
def test__set(self, serial_mock):
"""
Test the private set function of DisplayController
"""
serial = MagicMock()
serial.write = MagicMock()
dc = DisplayController(0, 9600)
dc._connection = serial
dc._set(0, 0)
serial.write.assert_has_calls([
call('1'),
call('0'),
call('0')
])
def test_output_pattern(self, serial_mock):
"""
This method ensures the prototype display controller can correctly output a pattern to the DisplayController.
"""
dc = DisplayController(0, 9600)
dc._connection = MagicMock()
dc._clear = MagicMock()
dc._set = MagicMock()
dc._draw = MagicMock()
dc.output_pattern("-*-\n-*-\n-*-")
# Ensure clear and draw were called once
dc._clear.assert_called_once_with()
dc._draw.assert_called_once_with()
# Test the set calls
dc._set.assert_has_calls([
call(1, 0),
call(1, 1),
call(1, 2)
])
def __init__(self):
"""
Ctor - Initialises the display driver, setting up the database helper and display controller.
"""
self._db_helper = DatabaseHelper(db_name)
self._display_controller = DisplayController(serial_name, serial_baudrate)
