Add proposed DSC Remote ID feeder parsing support

ogn/parser/parse.py

@@ -1,4 +1,5 @@
 from datetime import datetime, timezone
+import re
 
 from ogn.parser.utils import FPM_TO_MS, HPM_TO_DEGS, createTimestamp, KNOTS_TO_MS, KPH_TO_MS, FEETS_TO_METER, INCH_TO_MM, fahrenheit_to_celsius, CheapRuler, normalized_quality
 from ogn.parser.exceptions import AprsParseError
@@ -10,6 +11,7 @@
 
 dstcall_beacontype_mapping = {
     'OGCAPT': 'capturs',
+    'OGNDSC': 'dsc',
     'OGNFNT': 'fanet',
     'OGFLR': 'flarm',
     'OGFLR6': 'flarm',
@@ -146,6 +148,16 @@ def parse(aprs_message, reference_timestamp=None, calculate_relations=False, use
     else:
         raise ValueError("Raised unreachable exception")
 
+    if message.get('beacon_type') == 'dsc' and message['aprs_type'] == 'position':
+        # DSC proposal: provenance of the measurement timestamp, not a UTC accuracy claim.
+        codes = re.findall(r'(?:^|\s)dscT(\S*)(?=\s|$)', message.get('user_comment', ''))
+        if len(codes) == 1 and codes[0] in ('O', 'G', 'N', 'R'):
+            message['dsc_time_source'] = {
+                'O': 'device_fix', 'G': 'android_gnss_clock',
+                'N': 'android_network_clock', 'R': 'other_reconstruction',
+            }[codes[0]]
+            message['dsc_time_reconstructed'] = codes[0] != 'O'
+
     if message['aprs_type'].startswith('position') and calculate_relations is True:
         positions[message['name']] = (message['longitude'], message['latitude'])
         if message['receiver_name'] in positions:

tests/parser/parse/test_dsc.py

@@ -0,0 +1,32 @@
+# Synthetic offline fixtures only: ABC123 and DSCDEMO are not allocated.
+from datetime import datetime, timezone
+import pytest
+from ogn.parser import parse
+
+BASE = "OGNABC123>OGNDSC,qAR,DSCDEMO:/123456h4530.00N/00915.00E'360/021/A=000394 !W00! id37ABC123 +197fpm"
+
+@pytest.mark.parametrize('code,source,reconstructed', [('O','device_fix',False),('G','android_gnss_clock',True),('N','android_network_clock',True),('R','other_reconstruction',True)])
+def test_dsc_timestamp_provenance(code, source, reconstructed):
+    value=parse(BASE+' dscT'+code, datetime(2026,10,26,12,34,56,tzinfo=timezone.utc), use_server_timestamp=False)
+    assert value['beacon_type']=='dsc'
+    assert value['dsc_time_source']==source
+    assert value['dsc_time_reconstructed'] is reconstructed
+    assert value['address']=='ABC123'
+    assert value['timestamp'].isoformat()=='2026-10-26T12:34:56+00:00'
+    assert value['receiver_name']=='DSCDEMO'
+
+@pytest.mark.parametrize('suffix',['',' dscTX',' dscTG dscTN',' xdscTG',' dscTGjunk',' dscTG dscTX',' dscTG dscTG',' dscT',' dscTG dscT'])
+def test_absent_invalid_or_ambiguous_quality_not_invented(suffix):
+    assert 'dsc_time_source' not in parse(BASE+suffix)
+
+def test_dsc_field_does_not_change_other_feeders():
+    value=parse(BASE.replace('OGNDSC','OGNTRK')+' dscTG')
+    assert value['beacon_type']=='tracker'
+    assert 'dsc_time_source' not in value
+
+@pytest.mark.parametrize('path',['qOR','qAR,DSCDEMO','qAS,DSCDEMO'])
+def test_optional_altitude_and_motion(path):
+    value=parse("OGNABC123>OGNDSC,"+path+":/123456h4530.00N/00915.00E' !W00! id37ABC123 dscTG")
+    assert value['beacon_type']=='dsc'
+    assert 'altitude' not in value
+    assert 'ground_speed' not in value