alarms: refactor the alarms subsystem

also include eotk alarms now

app/alarms.py

@@ -1,48 +1,40 @@
 import datetime
-from typing import Optional
+from typing import Optional, List
 
 from app.extensions import db
 from app.models.alarms import Alarm
 
 
+def alarms_for(target: str) -> List[Alarm]:
+    return list(Alarm.query.filter(
+        Alarm.target == target
+    ).all())
+
+
 def _get_alarm(target: str,
-               alarm_type: str,
-               *,
-               proxy_id: Optional[int] = None,
-               origin_id: Optional[int] = None,
+               aspect: str,
                create_if_missing: bool = True) -> Optional[Alarm]:
-    alarm: Optional[Alarm]
-    if target == "proxy":
-        alarm = Alarm.query.filter(
-            Alarm.target == "proxy",
-            Alarm.alarm_type == alarm_type,
-            Alarm.proxy_id == proxy_id
-        ).first()
-    elif target == "origin":
-        alarm = Alarm.query.filter(
-            Alarm.target == "origin",
-            Alarm.alarm_type == alarm_type,
-            Alarm.proxy_id == origin_id
-        ).first()
-    else:
-        return None
+    alarm: Optional[Alarm] = Alarm.query.filter(
+        Alarm.aspect == aspect,
+        Alarm.target == target
+    ).first()
     if create_if_missing and alarm is None:
         alarm = Alarm()
+        alarm.aspect = aspect
         alarm.target = target
-        alarm.alarm_type = alarm_type
+        alarm.text = "New alarm"
         alarm.state_changed = datetime.datetime.utcnow()
-        if target == "proxy":
-            alarm.proxy_id = proxy_id
-        if target == "origin":
-            alarm.origin_id = origin_id
+        alarm.last_updated = datetime.datetime.utcnow()
         db.session.add(alarm)
-        db.session.commit()
     return alarm
 
 
-def get_proxy_alarm(proxy_id: int, alarm_type: str) -> Alarm:
-    alarm = _get_alarm("proxy", alarm_type, proxy_id=proxy_id)
+def get_alarm(target: str, aspect: str) -> Optional[Alarm]:
+    return _get_alarm(target, aspect, create_if_missing=False)
+
+
+def get_or_create_alarm(target: str, aspect: str) -> Alarm:
+    alarm = _get_alarm(target, aspect, create_if_missing=True)
     if alarm is None:
-        # mypy can't tell that this will never be reached
-        raise RuntimeError("Creating an alarm must have failed.")
+        raise RuntimeError("Asked for an alarm to be created but got None.")
     return alarm