Feat: Try read system set timezone and use this for es timestamp value

Replace hardcoded timezone offset. Noticed after we entered winter timezone.

source/logger.py

@@ -7,12 +7,13 @@ import uuid
 from datetime import datetime, date
 import urllib.request
 
-from utils import getConfig
+from utils import getConfig, timezoneOffset
 
 config = getConfig()
 LOGGER_NAME = config['logger']['name']
 esHost = config['elastic']['host']
 esPort = config['elastic']['port']
+systemTimezone = timezoneOffset()
 
 class ESHandler(logging.Handler):
   def __init__(self, *args, **kwargs):
@@ -25,7 +26,8 @@ class ESHandler(logging.Handler):
 
   def emit(self, record):
     self.format(record)
-    timestamp = datetime.fromtimestamp(record.created).strftime('%Y-%m-%dT%H:%M:%S.%f+02:00')
+    datetimeTemplate = '%Y-%m-%dT%H:%M:%S.%f{}'.format(systemTimezone)
+    timestamp = datetime.fromtimestamp(record.created).strftime(datetimeTemplate)
 
     indexURL = 'http://{}:{}/{}-{}/_doc'.format(self.host, self.port, LOGGER_NAME, self.date.strftime('%Y.%m.%d'))
 

source/utils.py

@@ -1,5 +1,6 @@
 #!/bin/usr/python3
 import os
+import subprocess
 import yaml
 
 def loadYaml(filePath):
@@ -20,3 +21,22 @@ def getConfig():
 
   return loadYaml(path)
 
+def timezoneOffset():
+  localTimezoneCommand = 'date +%z'
+  process = subprocess.Popen(localTimezoneCommand.split(), stdout=subprocess.PIPE)
+  output, error = process.communicate()
+
+  fallbackTimezone = '+0100'
+  if error:
+    print('Error when trying to fetch timezone: {}. Returning fallbacktimezone: {}.'.format(error, fallbackTimezone))
+    return fallbackTimezone
+
+  try:
+    output = output.decode("utf-8")
+    if '\n' in output:
+      output = output.replace('\n', '')
+    return output or fallbackTimezone
+  except Error as error:
+    print('Error occured while decoding output from system timezone: {}'.format(error))
+    return fallbackTimezone
+