Draft: Ingestion of SVOM ECLAIRS notices into LLAI workflow

This MR will ingest SVOM GRBs alerts detected by ECLAIRS instrument.

gwcelery/tasks/external_triggers.py

@@ -85,11 +85,12 @@ def handle_snews_gcn(payload):
              gcn.NoticeType.INTEGRAL_REFINED,
              gcn.NoticeType.INTEGRAL_OFFLINE,
              gcn.NoticeType.AGILE_MCAL_ALERT,
+             # gcn.NoticeType.SVOM_ECLAIRS_ALERT,
              queue='exttrig',
              shared=False)
 def handle_grb_gcn(payload):
-    """Handles the payload from Fermi, Swift, INTEGRAL, and AGILE MCAL
-    GCN notices.
+    """Handles the payload from Fermi, Swift, INTEGRAL, AGILE MCAL,
+    and SVOM ECLAIRS GCN notices.
 
     Filters out candidates likely to be noise. Creates external events
     from the notice if new notice, otherwise updates existing event. Then
@@ -101,6 +102,7 @@ def handle_grb_gcn(payload):
     Swift: https://gcn.gsfc.nasa.gov/swift.html
     INTEGRAL: https://gcn.gsfc.nasa.gov/integral.html
     AGILE-MCAL: https://gcn.gsfc.nasa.gov/agile_mcal.html
+    # SVOM-ECLAIRS: https://gcn.gsfc.nasa.gov/svom.html
 
     Parameters
     ----------
@@ -115,7 +117,8 @@ def handle_grb_gcn(payload):
     stream_obsv_dict = {'/SWIFT': 'Swift',
                         '/Fermi': 'Fermi',
                         '/INTEGRAL': 'INTEGRAL',
-                        '/AGILE': 'AGILE'}
+                        '/AGILE': 'AGILE',
+                        '/fsc': 'SVOM'}
     event_observatory = stream_obsv_dict[stream_path]
 
     ext_group = 'Test' if root.attrib['role'] == 'test' else 'External'
@@ -216,6 +219,7 @@ def handle_grb_gcn(payload):
                     'external_swift',
                     'external_integral',
                     'external_agile',
+                    'external_svom',
                     shared=False)
 def handle_grb_igwn_alert(alert):
     """Parse an IGWN alert message related to superevents/GRB external triggers
@@ -503,6 +507,46 @@ def handle_targeted_kafka_alert(alert):
     ).delay()
 
 
+@alerts.handler('svom')
+def handle_kafka_alert(alert):
+    """
+    Parse an SVOM alert sent via Kafka from a MOU partner in our joint
+    search for SVOM ECLAIRS GRBs, using the probability of astrophysical origin
+    (pastro) to vet events.
+
+    Parameters
+    ----------
+    alert : dict
+        Kafka alert packet containing SVOM event data.
+    """
+    # Convert alert to VOEvent format
+    payload, pipeline, time, trig_id = _kafka_to_voevent(alert)
+
+    # Use 'pastro' value to veto events likely being noise
+    pastro = alert.get('p_astro', 0)  # Handles if p_astro field is N/A.
+    pastro_threshold = 0.5  # Change later to conf. variable
+
+    # Veto events with 'pastro' value less than the threshold
+    label = 'NOT_GRB' if pastro < pastro_threshold else None
+
+    # Look whether a previous event with the same ID exists
+    query = (f'group: External pipeline: {pipeline} '
+             f'grbevent.trigger_id = "{trig_id}"')
+
+    # Chain tasks: query for events, then potentially create or replace
+    # an event and skymap
+    (
+        gracedb.get_events.si(query=query)
+        |
+        _create_replace_external_event_and_skymap.s(
+            payload, 'GRB', pipeline,
+            label=label, notice_date=time,
+            skymap=alert.get('healpix_file'),
+            use_radec=('ra' in alert and 'dec' in alert)
+        )
+    ).delay()
+
+
 def _skymaps_are_ready(event, label, task):
     """Determine whether labels are complete to launch a certain task.
 
@@ -717,7 +761,7 @@ def _create_replace_external_event_and_skymap(
 def _kafka_to_voevent(alert):
     """Parse an alert sent via Kafka from a MOU partner in our joint
     subthreshold targeted search and convert to an equivalent XML string
-    GCN VOEvent.
+    GCN VOEvent. Also, include handling for SVOM/ECLAIRs mission alert.
 
     Parameters
     ----------
@@ -728,14 +772,15 @@ def _kafka_to_voevent(alert):
     -------
     payload : str
         XML GCN notice alert packet in string format
-
+     payload, pipeline, time, trig_id
     """
     # Define basic values
     pipeline = alert['mission']
     start_time = alert['trigger_time']
     alert_time = alert['alert_datetime']
-    far = alert['far']
-    duration = alert['rate_duration']
+    far = alert.get('far')
+    snr = alert.get('image_snr')  # change this to make optional
+    duration = alert['image_duration']
     id = '_'.join(str(x) for x in alert['id'])
     # Use central time since starting time is not well measured
     central_time = \
@@ -747,7 +792,7 @@ def _kafka_to_voevent(alert):
     # sky localization may not be available
     ra = alert.get('ra')
     dec = alert.get('dec')
-    # Try to get dec first then ra, None if both misssing
+    # Try to get dec first then ra, None if both missing
     error = alert.get('dec_uncertainty')
     if error is None:
         error = alert.get('ra_uncertainty')
@@ -758,21 +803,35 @@ def _kafka_to_voevent(alert):
     if ra is None or dec is None or error is None:
         ra, dec, error = 0., 0., 0.
 
-    # Load template
-    fname = str(Path(__file__).parent /
-                '../tests/data/{}_subgrbtargeted_template.xml'.format(
-                    pipeline.lower()))
-    root = etree.parse(fname)
+    # Load template based on the mission
+    # FIXME: Need to adjust for targeted Fermi-Swift and SVOM/ECLAIRS GRBs
+    if pipeline.lower() in ['fermi', 'swift']:
+        fname = f'{pipeline.lower()}_subgrbtargeted_template.xml'
+        ivorn_suffix = 'targeted_subthreshold'
+    else:
+        fname = 'svom_grb_template.xml'  # change the saved filename
+        ivorn_suffix = 'grb'
+
+    # Construct the full path to the template
+    template_path = Path(__file__).parent / f'../tests/data/{fname}'
+    if not template_path.is_file():
+        raise FileNotFoundError(f'Template file {fname} not found '
+                                f'in ../tests/data')
+    root = etree.parse(str(template_path))
 
     # Update template values
-    # Change ivorn to indicate this is a subthreshold targeted event
-    root.xpath('.')[0].attrib['ivorn'] = \
-        'ivo://lvk.internal/{0}#targeted_subthreshold-{1}'.format(
-            pipeline.lower(), trigger_time).encode()
+    # Change ivorn to indicate this is subthreshold targeted event and SVOM grb
+    ivorn = \
+        f'ivo://lvk.internal/{pipeline.lower()}#{ivorn_suffix}-{trigger_time}'
+
+    root.xpath('.')[0].attrib['ivorn'] = ivorn
 
     # Update ID
-    root.find("./What/Param[@name='TrigID']").attrib['value'] = \
-        id.encode()
+    if pipeline.lower() in ['fermi', 'swift']:
+        root.find("./What/Param[@name='TrigID']").attrib['value'] = str(id)
+    else:
+        root.find("./What/Group[@name='Svom_Identifiers']"
+                  "/Param[@name='Burst_Id']").attrib['value'] = str(id)
 
     # Change times to chosen time
     root.find("./Who/Date").text = str(alert_time).encode()
@@ -780,11 +839,21 @@ def _kafka_to_voevent(alert):
                "ObservationLocation/AstroCoords/Time/TimeInstant/"
                "ISOTime")).text = str(trigger_time).encode()
 
-    root.find("./What/Param[@name='FAR']").attrib['value'] = \
-        str(far).encode()
+    if pipeline.lower() in ['fermi', 'swift']:
+        root.find("./What/Param[@name='FAR']").attrib['value'] = \
+            (str(far).encode())
+    else:
+        root.find("./Group[@name='Detection_Info']"
+                  "/Param[@name='SNR']").attrib['value'] = \
+            (str(snr).encode())
 
-    root.find("./What/Param[@name='Integ_Time']").attrib['value'] = \
-        str(duration).encode()
+    if pipeline.lower() in ['fermi', 'swift']:
+        root.find("./What/Param[@name='Integ_Time']").attrib['value'] = \
+            str(duration).encode()
+    else:
+        root.find("./Group[@name='Detection_Info']"          
+                  "/Param[@name='Timescale']").attrib['value'] = \
+            (str(duration).encode())
 
     # Sky position
     root.find(("./WhereWhen/ObsDataLocation/"