Handle case when tracker is down and flask lacks cache.

kappa123/server/runs.py

@@ -9,9 +9,12 @@ import logging
 
 CACHE_AGE_MAX = 600
 CACHE_LOCATION='/tmp/runs.json'
+TRACKER_URL='https://gamesdonequick.com/tracker/search/?type=run&event=20'
 
 logger = logging.getLogger(__name__)
 
+class KappaException(Exception):
+    pass
 class GDQException(Exception):
     pass
 
@@ -38,15 +41,18 @@ def fetch_or_cache_runs():
 
 
 def load_run_cache():
-    with open(CACHE_LOCATION, 'r') as f:
-        string = f.read()
-        return json.loads(string)
+    if os.path.isfile(CACHE_LOCATION):
+        with open(CACHE_LOCATION, 'r') as f:
+            string = f.read()
+            return json.loads(string)
+    else:
+        raise KappaException("GDQ Tracker Appears to be down, and I don't have a saved copy. Try again later.")
 
 
 def fetch_runs():
     try:
         logger.warn("Re-fetching cache")
-        r = requests.get('https://gamesdonequick.com/tracker/search/?type=run&event=20', timeout=3)
+        r = requests.get(TRACKER_URL, timeout=3)
         if r.status_code != 200:
             raise GDQException("GDQ not returning 200")
         output = r.json()