ogn-python/ogn/gateway/process.py

import logging
from math import log10

from mgrs import MGRS

from ogn.utils import haversine
from ogn.commands.dbutils import session
from ogn.model import AircraftBeacon, ReceiverBeacon, Location
from ogn.parser import parse, ParseError
from ogn.gateway.process_tools import DbSaver, Converter, DummyMerger, AIRCRAFT_TYPES, RECEIVER_TYPES


logger = logging.getLogger(__name__)
myMGRS = MGRS()



def _replace_lonlat_with_wkt(message, reference_receiver=None):
    latitude = message['latitude']
    longitude = message['longitude']

    if reference_receiver is not None:
        distance,bearing = haversine(reference_receiver['latitude'], reference_receiver['longitude'], latitude, longitude)
        message['distance'] = distance
        message['radial'] = round(bearing)
        if 'signal_quality' in message and message['signal_quality'] is not None and distance >= 1:
            message['quality'] = message['signal_quality'] + 20 * log10(message['distance'] / 10000)  # normalized to 10km

    location = Location(longitude, latitude)
    message['location_wkt'] = location.to_wkt()
    message['location_mgrs'] = myMGRS.toMGRS(latitude, longitude).decode('utf-8')
    del message['latitude']
    del message['longitude']
    return message


receivers = dict()

def string_to_message(raw_string, reference_date):
    global receivers

    try:
        message = parse(raw_string, reference_date)
    except NotImplementedError as e:
        logger.error('No parser implemented for message: {}'.format(raw_string))
        return None
    except ParseError as e:
        logger.error('Parsing error with message: {}'.format(raw_string))
        return None
    except TypeError as e:
        logger.error('TypeError with message: {}'.format(raw_string))
        return None
    except Exception as e:
        logger.error(raw_string)
        logger.error(e)
        return None

    # update reference receivers and distance to the receiver
    if message['aprs_type'] == 'position':
        if message['beacon_type'] in RECEIVER_TYPES:
            receivers.update({message['name']: {'latitude': message['latitude'], 'longitude': message['longitude']}})
            message = _replace_lonlat_with_wkt(message)
        elif message['beacon_type'] in AIRCRAFT_TYPES:
            reference_receiver = receivers.get(message['receiver_name'])
            message = _replace_lonlat_with_wkt(message, reference_receiver=reference_receiver)
            if 'gps_quality' in message and message['gps_quality'] is not None and 'horizontal' in message['gps_quality']:
                message['gps_quality_horizontal'] = message['gps_quality']['horizontal']
                message['gps_quality_vertical'] = message['gps_quality']['vertical']

    # update raw_message
    message['raw_message'] = raw_string

    return message


# Build the processing pipeline
saver = DbSaver(session=session)
converter = Converter(callback=saver)
merger = DummyMerger(callback=converter)


def process_raw_message(raw_message, reference_date=None, merger=merger):
    logger.debug('Received message: {}'.format(raw_message))
    message = string_to_message(raw_message, reference_date)
    merger.add_message(message)