From ee705fe7a9b98dc5414a6e12c78e3d51a49b5734 Mon Sep 17 00:00:00 2001
From: Jimmy Zelinskie <jimmy.zelinskie@coreos.com>
Date: Tue, 9 Feb 2016 15:20:52 -0500
Subject: [PATCH] vastly simplify log rotation

---
 data/model/log.py          |  2 +-
 workers/logrotateworker.py | 60 +++++++++++++++-----------------------
 2 files changed, 24 insertions(+), 38 deletions(-)

diff --git a/data/model/log.py b/data/model/log.py
index a2037e6f7..5b32e3fb1 100644
--- a/data/model/log.py
+++ b/data/model/log.py
@@ -133,7 +133,7 @@ def get_stale_logs_start_id():
     return None
 
 
-def get_stale_logs_end_id(cutoff_date):
+def get_stale_logs_cutoff_id(cutoff_date):
   """ Gets the most recent ID created before the cutoff_date. """
   try:
     return (LogEntry
diff --git a/workers/logrotateworker.py b/workers/logrotateworker.py
index 40bb690a8..2baa1b0ec 100644
--- a/workers/logrotateworker.py
+++ b/workers/logrotateworker.py
@@ -3,23 +3,21 @@ import json
 import time
 
 from datetime import timedelta, datetime
-from itertools import chain
 
 import features
 from app import app, storage
 from data.database import UseThenDisconnect
 from data.model import db_transaction
 from data.model.log import (get_stale_logs, get_stale_logs_start_id,
-                            get_stale_logs_end_id, delete_stale_logs)
+                            get_stale_logs_cutoff_id, delete_stale_logs)
 from util.registry.gzipwrap import GzipWrap
 from workers.globalworkerbase import GlobalWorker
 
 logger = logging.getLogger(__name__)
 
-WORKER_FREQUENCY = 3600
+WORKER_FREQUENCY = 3600 * 6
 STALE_AFTER = timedelta(days=30)
 MIN_LOGS_PER_ROTATION = 10000
-BATCH_SIZE = 500
 SAVE_PATH = app.config.get('ACTION_LOG_ARCHIVE_PATH')
 SAVE_LOCATION = app.config.get('ACTION_LOG_ARCHIVE_LOCATION')
 
@@ -30,47 +28,35 @@ class LogRotateWorker(GlobalWorker):
 
   def perform_global_work(self):
     logger.debug('Attempting to rotate log entries')
-    with UseThenDisconnect(app.config):
-      with db_transaction():
-        cutoff = datetime.now() - STALE_AFTER
-        start_id = get_stale_logs_start_id()
-        end_id = get_stale_logs_end_id(cutoff)
+    while True:
+      with UseThenDisconnect(app.config):
+        with db_transaction():
+          cutoff_date = datetime.now() - STALE_AFTER
+          start_id = get_stale_logs_start_id()
+          cutoff_id = get_stale_logs_cutoff_id(cutoff_date)
 
-        if start_id is None or end_id is None:
-          logger.warning('No logs to be archived.')
-          return
+          if start_id is None or cutoff_id is None:
+            logger.warning('No logs to be archived.')
+            return
 
-        logger.debug('Found starting ID %s and ending ID %s', start_id, end_id)
+          logger.debug('Found starting ID %s and cutoff ID %s', start_id, cutoff_id)
 
-        approx_count = end_id - start_id
-        if approx_count < MIN_LOGS_PER_ROTATION:
-          logger.debug('Not enough stale logs to warrant rotation (approx %d)', approx_count)
-          return
+          approx_count = cutoff_id - start_id
+          if approx_count < MIN_LOGS_PER_ROTATION:
+            logger.debug('Not enough stale logs to warrant rotation (approx %d)', approx_count)
+            return
 
-        # Build a generator of all the logs we want to archive in batches of 500.
-        log_generator = (_ for _ in ())
-        logs_to_fetch = range(start_id, end_id+1)
-        while len(logs_to_fetch) != 0:
-          (batch, logs_to_fetch) = _take(BATCH_SIZE, logs_to_fetch)
-          logger.debug('Reading archived logs from IDs %s to %s', batch[0], batch[-1])
-          batch_generator = (pretty_print_in_json(log) + '\n'
-                             for log in get_stale_logs(batch[0], batch[-1]))
-          log_generator = chain(log_generator, batch_generator)
+          end_id = start_id + MIN_LOGS_PER_ROTATION
+          logs = (pretty_print_in_json(log)
+                  for log in get_stale_logs(start_id, end_id))
 
-        logger.debug('Archiving logs from IDs %s to %s', start_id, end_id)
-        filename = '%s%d-%d.txt.gz' % (SAVE_PATH, start_id, end_id)
-        storage.stream_write(SAVE_LOCATION, filename, GzipWrap(log_generator))
+          logger.debug('Archiving logs from IDs %s to %s', start_id, end_id)
+          filename = '%s%d-%d.txt.gz' % (SAVE_PATH, start_id, end_id)
+          storage.stream_write(SAVE_LOCATION, filename, GzipWrap(logs))
 
-        logs_to_delete = range(start_id, end_id+1)
-        while len(logs_to_delete) != 0:
-          (batch, logs_to_delete) = _take(BATCH_SIZE, logs_to_delete)
-          logger.debug('Deleting archived logs from IDs %s to %s', batch[0], batch[-1])
-          delete_stale_logs(batch[0], batch[-1])
+          delete_stale_logs(start_id, end_id)
 
 
-def _take(count, lst):
-  return lst[:count], lst[count:]
-
 def pretty_print_in_json(log):
   """ Pretty prints a LogEntry in JSON. """
   return json.dumps({'kind_id': log.kind_id,