[RFC] Logging

eg:
----
/var/log/[microservice-name]/[microservice-name]-error.log   # error only
/var/log/[microservice-name]/[microservice-name].log         # info, warning & debug

eg: INFO
---
{
  "datetime": "2020-10-10 20:01:59TZ+0700"
  "severity": "info",
  "message": "yes, this is info"
}

eg: WARNING
---
{
  "datetime": "2020-10-10 20:01:59TZ+0700"
  "severity": "warning",
  "message": "this is warning"
}

eg: ERROR
---
{
  "datetime": "2020-10-10 20:01:59TZ+0700"
  "severity": "error",
  "code": 404
  "message": "not found"
}

eg: DEBUG (optional)
---
{
  "datetime": "2020-10-10 20:01:59TZ+0700"
  "severity": "debug",
  "code": 100
  "message": "describe debug information (criteria by number) "
}

# /etc/logrotate.d/[microservice-name]
---
/var/log/[microservice-name]/[microservice-name].log {
        rotate 12
        weekly
        missingok
        notifempty
        compress
        delaycompress
        size 50M
        notifempty
        sharedscripts
        postrotate
           /usr/bin/killall -HUP [microservice-name]
        endscript
}

/var/log/[microservice-name]/[microservice-name]-error.log {
        rotate 12
        weekly
        missingok
        notifempty
        compress
        delaycompress
        size 50M
        notifempty
        sharedscripts
        postrotate
           /usr/bin/killall -HUP [microservice-name]
        endscript
}

# log4j.properties
---
log4j.rootLogger=INFO, fileLogger
log4j.appender.fileLogger=org.apache.log4j.RollingFileAppender
log4j.appender.fileLogger.layout=org.apache.log4j.PatternLayout
log4j.appender.fileLogger.layout.ConversionPattern=%d [%t] %-5p (%F:%L) - %m%n
log4j.appender.fileLogger.File=example.log
log4j.appender.fileLogger.MaxFileSize=50MB
log4j.appender.fileLogger.MaxBackupIndex=12

/etc/cron.d/[microservice-name]

/etc/systemd/system/[microservice-name].service
/etc/systemd/system/[microservice-name].timer

from datetime import datetime
import logging
import time
import json
       
def main():
    print("--- Staring Log Exporter Agent ---")
    logging.basicConfig(level=logging.INFO, filename="/var/log/[microservice-name]/[microservice-name].log", format="%(message)s")

if __name__ == '__main__':
    main()