Further alert implementation #17

data/alert.py

@@ -1,7 +1,9 @@
+import hashlib
 import json
 from dataclasses import dataclass
 from datetime import datetime
 
+import copy
 import pytz
 
 from core.constants import DXCC_FLAGS
@@ -14,7 +16,7 @@ from core.utils import infer_continent_from_callsign, \
 @dataclass
 class Alert:
     # Unique identifier for the alert
-    id: int = None
+    id: str = None
     # Callsign of the operator that has been alertted
     dx_call: str = None
     # Name of the operator that has been alertted
@@ -103,8 +105,15 @@ class Alert:
         if self.dx_call and not self.dx_name:
             self.dx_name = infer_name_from_callsign(self.dx_call)
 
-        # Always create an ID based on a hashcode
-        self.id = hash(str(self))
+        # Always create an ID based on a hash of every parameter *except* received_time. This is used as the index
+        # to a map, which as a byproduct avoids us having multiple duplicate copies of the object that are identical
+        # apart from that they were retrieved from the API at different times. Note that the simple Python hash()
+        # function includes a seed randomly generated at runtime; this is therefore not consistent between runs. But we
+        # use diskcache to store our data between runs, so we use SHA256 which does not include this random element.
+        self_copy = copy.deepcopy(self)
+        self_copy.received_time = 0
+        self_copy.received_time_iso = ""
+        self.id = hashlib.sha256(str(self_copy).encode("utf-8")).hexdigest()
 
     # JSON serialise
     def to_json(self):