def _write_config_file(run_as_user):
caps = list_caps()
if 'Credentials' not in caps:
log.warning('Cannot obtain Jupyter password; will bail.')
sys.exit(1)
creds = acquire('Credentials')
jupyter_password = None
while True:
jupyter_password = creds.get_jupyter_password()
if jupyter_password is not None:
break
log.info('Waiting for Jupyter password to be set...')
time.sleep(1)
release(creds)
log.info('Got Jupyter password.')
user_home_dir_path = pwd.getpwnam(run_as_user).pw_dir
with open(JUPYTER_CONFIG_TEMPLATE, 'r') as f_template:
template = f_template.read()
with open(JUPYTER_CONFIG_OUTPUT, 'w') as f_out:
final_config = template
final_config = final_config.replace(r'<JUPYTER_PASSWORD>',
repr(jupyter_password))
final_config = final_config.replace(r'<JUPYTER_START_DIR>',
repr(user_home_dir_path))
f_out.write(final_config)
def _get_gyro_accum():
global _GYRO_ACCUM
try:
_GYRO_ACCUM
except NameError:
caps = list_caps()
if 'Gyroscope_accum' not in caps:
raise AttributeError('This device has no gyroscope.')
_GYRO_ACCUM = acquire('Gyroscope_accum')
return _GYRO_ACCUM
def _get_pid_steering():
global _PID_STEERING
try:
_PID_STEERING
except NameError:
caps = list_caps()
if 'PID_steering' not in caps:
raise AttributeError('This device has no PID steering loop.')
_PID_STEERING = acquire('PID_steering')
return _PID_STEERING
def _get_encoder():
global _ENCODER
try:
_ENCODER
except NameError:
caps = list_caps()
if 'Encoders' not in caps:
raise AttributeError('This device has no encoder.')
_ENCODER = acquire('Encoders')
_ENCODER.enable(ENCODER_INDEX)
return _ENCODER
def _get_motors():
global _MOTORS
try:
_MOTORS
except NameError:
caps = list_caps()
if 'CarMotors' not in caps:
raise AttributeError('This device is not a car.')
_MOTORS = acquire('CarMotors')
_MOTORS.on()
return _MOTORS
def buzz(notes):
"""
Play the given `notes` on the device's buzzer.
"""
global _BUZZER
try:
_BUZZER
except NameError:
caps = list_caps()
if 'Buzzer' not in caps:
raise AttributeError("This device does not have a buzzer.")
_BUZZER = acquire('Buzzer')
_BUZZER.play(notes)
_BUZZER.wait()
def global_camera(verbose=False):
"""
Creates (for the first call) or retrieves (for later calls) the
global camera object. This is a convenience function to facilitate
quickly and easily creating and retrieving a camera singleton.
"""
global GLOBAL_CAMERA
try:
GLOBAL_CAMERA
except NameError:
caps = list_caps()
if 'Camera' not in caps:
raise AttributeError("This device does not have a Camera.")
camera = acquire('Camera')
GLOBAL_CAMERA = _CameraRGB(camera)
if verbose:
auto._ctx_print_all("Instantiated a global camera object!")
return GLOBAL_CAMERA
def get_servo(servo_index, frequency=50, min_duty=0.025, max_duty=0.125):
"""
Acquire the interface to the servo at index `servo_index`.
The first servo is at index 0.
"""
global _PWMs
try:
_PWMs
except NameError:
caps = list_caps()
if 'PWMs' not in caps:
raise AttributeError("This device does not have a PWM controller.")
_PWMs = acquire('PWMs')
n_pins = _PWMs.num_pins()
if servo_index < 0 or servo_index >= n_pins:
raise Exception(
"Invalid servo index given: {}. This device has servos 0 through {}"
.format(servo_index, n_pins - 1))
return _ServoTemplate(_PWMs, servo_index, frequency, min_duty, max_duty)