PX4-Autopilot/Tools/mavlink_ulog_streaming.py
Julian Oes 9a96ca14be Tools: make Python import error more readable
The problem with printing the exception was that starting with
Python 3.6 the ImportError is yet another (sub) exception called
ModuleNotFoundError which can't be printed as a string and then triggers
another exception:

```
Traceback (most recent call last):
  File "/home/julianoes/src/Firmware/Tools/serial/generate_config.py", line 11, in <module>
    import jinja2
ModuleNotFoundError: No module named 'jinja2'

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/home/julianoes/src/Firmware/Tools/serial/generate_config.py", line 13, in <module>
    print("Failed to import jinja2: " + e)
TypeError: must be str, not ModuleNotFoundError
```

As per @bkueng's suggestion the easiest is to cast the exception to str
and that way prevent the second exception.
2020-02-14 11:40:05 +01:00

271 lines
9.9 KiB
Python
Executable File

#!/usr/bin/env python3
"""
Stream ULog data over MAVLink.
@author: Beat Kueng (beat-kueng@gmx.net)
"""
from __future__ import print_function
import sys, select, os
import datetime
from timeit import default_timer as timer
os.environ['MAVLINK20'] = '1' # The commands require mavlink 2
from argparse import ArgumentParser
try:
from pymavlink import mavutil
except ImportError as e:
print("Failed to import pymavlink: " + str(e))
print("")
print("You may need to install it with:")
print(" pip3 install --user pymavlink")
print("")
sys.exit(1)
class MavlinkLogStreaming():
'''Streams log data via MAVLink.
Assumptions:
- the sender only sends one acked message at a time
- the data is in the ULog format '''
def __init__(self, portname, baudrate, output_filename, debug=0):
self.baudrate = 0
self._debug = debug
self.buf = ''
self.debug("Connecting with MAVLink to %s ..." % portname)
self.mav = mavutil.mavlink_connection(portname, autoreconnect=True, baud=baudrate)
self.mav.wait_heartbeat()
self.debug("HEARTBEAT OK\n")
self.debug("Locked serial device\n")
self.got_ulog_header = False
self.got_header_section = False
self.ulog_message = []
self.file = open(output_filename,'wb')
self.start_time = timer()
self.last_sequence = -1
self.logging_started = False
self.num_dropouts = 0
self.target_component = 1
def debug(self, s, level=1):
'''write some debug text'''
if self._debug >= level:
print(s)
def start_log(self):
self.mav.mav.command_long_send(self.mav.target_system,
self.target_component,
mavutil.mavlink.MAV_CMD_LOGGING_START, 0,
0, 0, 0, 0, 0, 0, 0)
def stop_log(self):
self.mav.mav.command_long_send(self.mav.target_system,
self.target_component,
mavutil.mavlink.MAV_CMD_LOGGING_STOP, 0,
0, 0, 0, 0, 0, 0, 0)
def read_messages(self):
''' main loop reading messages '''
measure_time_start = timer()
measured_data = 0
next_heartbeat_time = timer()
while True:
# handle heartbeat sending
heartbeat_time = timer()
if heartbeat_time > next_heartbeat_time:
self.debug('sending heartbeat')
self.mav.mav.heartbeat_send(mavutil.mavlink.MAV_TYPE_GCS,
mavutil.mavlink.MAV_AUTOPILOT_GENERIC, 0, 0, 0)
next_heartbeat_time = heartbeat_time + 1
m, first_msg_start, num_drops = self.read_message()
if m is not None:
self.process_streamed_ulog_data(m, first_msg_start, num_drops)
# status output
if self.logging_started:
measured_data += len(m)
measure_time_cur = timer()
dt = measure_time_cur - measure_time_start
if dt > 1:
sys.stdout.write('\rData Rate: {:0.1f} KB/s Drops: {:} \033[K'.format(
measured_data / dt / 1024, self.num_dropouts))
sys.stdout.flush()
measure_time_start = measure_time_cur
measured_data = 0
if not self.logging_started and timer()-self.start_time > 4:
raise Exception('Start timed out. Is the logger running in MAVLink mode?')
def read_message(self):
''' read a single mavlink message, handle ACK & return a tuple of (data, first
message start, num dropouts) '''
m = self.mav.recv_match(type=['LOGGING_DATA_ACKED',
'LOGGING_DATA', 'COMMAND_ACK'], blocking=True,
timeout=0.05)
if m is not None:
self.debug(m, 3)
if m.get_type() == 'COMMAND_ACK':
if m.command == mavutil.mavlink.MAV_CMD_LOGGING_START and \
not self.got_header_section:
if m.result == 0:
self.logging_started = True
print('Logging started. Waiting for Header...')
else:
raise Exception('Logging start failed', m.result)
return None, 0, 0
# m is either 'LOGGING_DATA_ACKED' or 'LOGGING_DATA':
is_newer, num_drops = self.check_sequence(m.sequence)
# return an ack, even we already sent it for the same sequence,
# because the ack could have been dropped
if m.get_type() == 'LOGGING_DATA_ACKED':
self.mav.mav.logging_ack_send(self.mav.target_system,
self.target_component, m.sequence)
if is_newer:
if num_drops > 0:
self.num_dropouts += num_drops
if m.get_type() == 'LOGGING_DATA':
if not self.got_header_section:
print('Header received in {:0.2f}s'.format(timer()-self.start_time))
self.logging_started = True
self.got_header_section = True
self.last_sequence = m.sequence
return m.data[:m.length], m.first_message_offset, num_drops
else:
self.debug('dup/reordered message '+str(m.sequence))
return None, 0, 0
def check_sequence(self, seq):
''' check if a sequence is newer than the previously received one & if
there were dropped messages between the last and this '''
if self.last_sequence == -1:
return True, 0
if seq == self.last_sequence: # duplicate
return False, 0
if seq > self.last_sequence:
# account for wrap-arounds, sequence is 2 bytes
if seq - self.last_sequence > (1<<15): # assume reordered
return False, 0
return True, seq - self.last_sequence - 1
else:
if self.last_sequence - seq > (1<<15):
return True, (1<<16) - self.last_sequence - 1 + seq
return False, 0
def process_streamed_ulog_data(self, data, first_msg_start, num_drops):
''' write streamed data to a file '''
if not self.got_ulog_header: # the first 16 bytes need special treatment
if len(data) < 16: # that's never the case anyway
raise Exception('first received message too short')
self.file.write(bytearray(data[0:16]))
data = data[16:]
self.got_ulog_header = True
if self.got_header_section and num_drops > 0:
if num_drops > 25: num_drops = 25
# write a dropout message. We don't really know the actual duration,
# so just use the number of drops * 10 ms
self.file.write(bytearray([ 2, 0, 79, num_drops*10, 0 ]))
if num_drops > 0:
self.write_ulog_messages(self.ulog_message)
self.ulog_message = []
if first_msg_start == 255:
return # no useful information in this message: drop it
data = data[first_msg_start:]
first_msg_start = 0
if first_msg_start == 255 and len(self.ulog_message) > 0:
self.ulog_message.extend(data)
return
if len(self.ulog_message) > 0:
self.file.write(bytearray(self.ulog_message + data[:first_msg_start]))
self.ulog_message = []
data = self.write_ulog_messages(data[first_msg_start:])
self.ulog_message = data # store the rest for the next message
def write_ulog_messages(self, data):
''' write ulog data w/o integrity checking, assuming data starts with a
valid ulog message. returns the remaining data at the end. '''
while len(data) > 2:
message_length = data[0] + data[1] * 256 + 3 # 3=ULog msg header
if message_length > len(data):
break
self.file.write(bytearray(data[:message_length]))
data = data[message_length:]
return data
def main():
parser = ArgumentParser(description=__doc__)
parser.add_argument('port', metavar='PORT', nargs='?', default = None,
help='Mavlink port name: serial: DEVICE[,BAUD], udp: IP:PORT, tcp: tcp:IP:PORT. Eg: \
/dev/ttyUSB0 or 0.0.0.0:14550. Auto-detect serial if not given.')
parser.add_argument("--baudrate", "-b", dest="baudrate", type=int,
help="Mavlink port baud rate (default=115200)", default=115200)
parser.add_argument("--output", "-o", dest="output", default = '.',
help="output file or directory (default=CWD)")
args = parser.parse_args()
if os.path.isdir(args.output):
filename = datetime.datetime.now().strftime("%Y-%m-%d_%H-%M-%S.ulg")
filename = os.path.join(args.output, filename)
else:
filename = args.output
print('Output file name: {:}'.format(filename))
if args.port == None:
serial_list = mavutil.auto_detect_serial(preferred_list=['*FTDI*',
"*Arduino_Mega_2560*", "*3D_Robotics*", "*USB_to_UART*", '*PX4*', '*FMU*'])
if len(serial_list) == 0:
print("Error: no serial connection found")
return
if len(serial_list) > 1:
print('Auto-detected serial ports are:')
for port in serial_list:
print(" {:}".format(port))
print('Using port {:}'.format(serial_list[0]))
args.port = serial_list[0].device
print("Connecting to MAVLINK...")
mav_log_streaming = MavlinkLogStreaming(args.port, args.baudrate, filename)
try:
print('Starting log...')
mav_log_streaming.start_log()
mav_log_streaming.read_messages()
print('Stopping log')
mav_log_streaming.stop_log()
except KeyboardInterrupt:
print('Stopping log')
mav_log_streaming.stop_log()
if __name__ == '__main__':
main()