python-ogn-client/ogn/parser/parse.py

import re
from datetime import datetime

from ogn.parser.utils import createTimestamp, parseAngle, kts2kmh, feet2m
from ogn.parser.pattern import PATTERN_APRS, PATTERN_APRS_POSITION, PATTERN_APRS_STATUS, PATTERN_APRS_SERVER
from ogn.parser.exceptions import AprsParseError, OgnParseError

from ogn.parser.aprs_comment.ogn_parser import OgnParser
from ogn.parser.aprs_comment.lt24_parser import LT24Parser
from ogn.parser.aprs_comment.naviter_parser import NaviterParser
from ogn.parser.aprs_comment.flarm_parser import FlarmParser
from ogn.parser.aprs_comment.tracker_parser import TrackerParser
from ogn.parser.aprs_comment.receiver_parser import ReceiverParser
from ogn.parser.aprs_comment.skylines_parser import SkylinesParser
from ogn.parser.aprs_comment.spider_parser import SpiderParser
from ogn.parser.aprs_comment.spot_parser import SpotParser


def parse(aprs_message, reference_date=None, reference_time=None):
    if reference_date is None:
        now = datetime.utcnow()
        reference_date = now.date()
        reference_time = now.time()

    message = parse_aprs(aprs_message, reference_date, reference_time)
    if message['aprs_type'] == 'position' or message['aprs_type'] == 'status':
        message.update(parse_comment(message['comment'],
                                     dstcall=message['dstcall'],
                                     aprs_type=message['aprs_type']))
    return message


def parse_aprs(message, reference_date, reference_time=None):
    if message and message[0] == '#':
        match_server = re.search(PATTERN_APRS_SERVER, message)
        if match_server:
            return {'version': match_server.group('version'),
                    'timestamp': datetime.strptime(match_server.group('timestamp'), "%d %b %Y %H:%M:%S %Z"),
                    'server': match_server.group('server'),
                    'ip_address': match_server.group('ip_address'),
                    'port': match_server.group('port'),
                    'aprs_type': 'server'}
        else:
            return {'comment': message,
                    'aprs_type': 'comment'}

    match = re.search(PATTERN_APRS, message)
    if match:
        aprs_type = 'position' if match.group('aprs_type') == '/' else 'status'
        aprs_body = match.group('aprs_body')
        if aprs_type == 'position':
            match_position = re.search(PATTERN_APRS_POSITION, aprs_body)
            if match_position:
                return {'name': match.group('callsign'),
                        'dstcall': match.group('dstcall'),
                        'relay': match.group('relay') if match.group('relay') else None,
                        'receiver_name': match.group('receiver'),
                        'timestamp': createTimestamp(match_position.group('time'), reference_date, reference_time),
                        'latitude': parseAngle('0' + match_position.group('latitude') + (match_position.group('latitude_enhancement') or '0')) *
                        (-1 if match_position.group('latitude_sign') == 'S' else 1),
                        'symboltable': match_position.group('symbol_table'),
                        'longitude': parseAngle(match_position.group('longitude') + (match_position.group('longitude_enhancement') or '0')) *
                        (-1 if match_position.group('longitude_sign') == 'W' else 1),
                        'symbolcode': match_position.group('symbol'),
                        'track': int(match_position.group('course')) if match_position.group('course_extension') else None,
                        'ground_speed': int(match_position.group('ground_speed')) * kts2kmh if match_position.group('ground_speed') else None,
                        'altitude': int(match_position.group('altitude')) * feet2m,
                        'comment': match_position.group('comment') if match_position.group('comment') else "",
                        'aprs_type': aprs_type}
        elif aprs_type == 'status':
            match_status = re.search(PATTERN_APRS_STATUS, aprs_body)
            if match_status:
                return {'name': match.group('callsign'),
                        'dstcall': match.group('dstcall'),
                        'receiver_name': match.group('receiver'),
                        'timestamp': createTimestamp(match_status.group('time'), reference_date, reference_time),
                        'comment': match_status.group('comment') if match_status.group('comment') else "",
                        'aprs_type': aprs_type}

    raise AprsParseError(message)


dstcall_parser_mapping = {'APRS': OgnParser(),
                          'OGFLR': FlarmParser(),
                          'OGNTRK': TrackerParser(),
                          'OGNSDR': ReceiverParser(),
                          'OGLT24': LT24Parser(),
                          'OGNAVI': NaviterParser(),
                          'OGSKYL': SkylinesParser(),
                          'OGSPID': SpiderParser(),
                          'OGSPOT': SpotParser(),
                          }


def parse_comment(aprs_comment, dstcall='APRS', aprs_type="position"):
    parser = dstcall_parser_mapping.get(dstcall)
    if parser:
        return parser.parse(aprs_comment, aprs_type)
    else:
        raise OgnParseError("No parser for dstcall {} found. APRS comment: {}".format(dstcall, aprs_comment))