Disk-based caching for spots so they survive a software restart

providers/provider.py

@@ -3,7 +3,7 @@ from datetime import datetime
 import pytz
 
 from core.constants import SOFTWARE_NAME, SOFTWARE_VERSION
-from core.config import config, SERVER_OWNER_CALLSIGN
+from core.config import config, SERVER_OWNER_CALLSIGN, MAX_SPOT_AGE
 
 
 # Generic data provider class. Subclasses of this query the individual APIs for data.
@@ -19,11 +19,11 @@ class Provider:
         self.last_update_time = datetime.min.replace(tzinfo=pytz.UTC)
         self.last_spot_time = datetime.min.replace(tzinfo=pytz.UTC)
         self.status = "Not Started" if self.enabled else "Disabled"
-        self.spot_list = None
+        self.spots = None
 
     # Set up the provider, e.g. giving it the spot list to work from
-    def setup(self, spot_list):
-        self.spot_list = spot_list
+    def setup(self, spots):
+        self.spots = spots
 
     # Start the provider. This should return immediately after spawning threads to access the remote resources
     def start(self):
@@ -38,8 +38,8 @@ class Provider:
             if spot.time > self.last_spot_time:
                 # Fill in any blanks
                 spot.infer_missing()
-                # Append to the list
-                self.spot_list.append(spot)
+                # Add to the list
+                self.spots.add(spot.guid, spot, expire=MAX_SPOT_AGE)
         self.last_spot_time = max(map(lambda s: s.time, spots))
 
     # Submit a single spot retrieved from the provider. This will be added to the list regardless of its age. Spots
@@ -48,8 +48,8 @@ class Provider:
     def submit(self, spot):
         # Fill in any blanks
         spot.infer_missing()
-        # Append to the list
-        self.spot_list.append(spot)
+        # Add to the list
+        self.spots.add(spot.guid, spot, expire=MAX_SPOT_AGE)
         self.last_spot_time = spot.time
 
     # Stop any threads and prepare for application shutdown