option to enable build-in log rotation enabled leveraging glog

[wey-gu]

ref: https://discuss.nebula-graph.com.cn/t/topic/13787/9?u=wey

cc @yixinglu

[jyf111]

As discussed in the forum, glog provides --max_log_size=x option. When the log file size exceeds x MB, glog will create and write to a new file, but the old file is never automatically deleted.

Besides, when setting --timestamp_in_logfile_name=false, --max_log_size no longer works. Because without the timestamp, the new file name is the same as the old file, and glog sets the append attribute.

To automatically delete over-sized old files, glog provides google::EnableLogCleaner(overdue_days). It scans the log dir and removes files with names matching <program name>.<hostname>.<user name>.log.<severity level> (to avoid mistaken deletion) and that have not been modified for over overdue_days, whenever a flush is performed. To avoid frequent scans, glog v0.6 also provides --logcleansecs=x option, then it scans again only after x secs.

So, I think we can add a logcleandays option, and just add the following code to src/daemons/SetupLogging.cpp.

if (FLAGS_logcleandays > 0) {
  google::EnableLogCleaner(FLAGS_logcleandays);
}

We may also add max_log_size=1800, log_clean_days=0 and stop_logging_if_full_disk=false to *.conf.default.

Then, edit max_log_size=x, log_clean_days=y, stop_logging_if_full_disk=true (optional) in *.conf to enable (approximate) log roration.

[Aanchallllll]

Hello,
would like to contribute.can i be assigned?