Using only sql statement, removed python and logging

ckan/migration/versions/085_adjust_activity_timestamps.py

@@ -1,33 +1,14 @@
 # encoding: utf-8
 
-import pytz
-import tzlocal
-import logging
-
-log = logging.getLogger(__name__)
+import datetime
 
 def upgrade(migrate_engine):
-"""
-The script assumes that the current timestamp was recorded with the server's current set timezone
-"""
-    local_tz = tzlocal.get_localzone()
+    """
+    The script assumes that the current timestamp was recorded with the server's current set timezone
+    """
+    utc_now = datetime.datetime.utcnow()
+    local_now = datetime.datetime.now()
 
     with migrate_engine.begin() as connection:
-        sql = "select id, timestamp from activity"
-        results = connection.execute(sql)
-
-        log.info("Adjusting Activity timestamp, server's localtime zone: {tz}".format(tz=local_tz))
-
-        for row in results:
-            id, timestamp = row
-
-            timestamp = timestamp.replace(tzinfo=local_tz)
-            to_utc = timestamp.astimezone(pytz.utc)
-            to_utc = to_utc.replace(tzinfo=None)
-
-            update_sql = "update activity set timestamp = %s where id = %s"
-
-            connection.execute(update_sql, to_utc, id)
-
-            log.info("""Adjusting Activity timestamp to UTC for {id}: {old_ts} --> {new_ts}
-            """.format(id=id, old_ts=timestamp, new_ts=to_utc))
+        sql = "update activity set timestamp = timestamp + (%s - %s);"
+        connection.execute(sql, utc_now, local_now)