Set redis logs entries to expire rather than to immediately delete them to make the logs archiver idempotent.

data/buildlogs.py

@@ -2,6 +2,11 @@ import redis
 import json
 
 from util.dynamic import import_class
+from datetime import timedelta
+
+
+ONE_DAY = timedelta(days=1)
+
 
 class BuildStatusRetrievalError(Exception):
   pass
@@ -54,11 +59,11 @@ class RedisBuildLogs(object):
     except redis.ConnectionError:
       raise BuildStatusRetrievalError('Cannot retrieve build logs')
 
-  def delete_log_entries(self, build_id):
+  def expire_log_entries(self, build_id):
     """
-    Deletes the logs and status keys completely.
+    Sets the log entry to expire in 1 day.
     """
-    self._redis.delete(self._logs_key(build_id))
+    self._redis.expire(self._logs_key(build_id), ONE_DAY)
 
 
   @staticmethod