Improve logging output

Author: jan-di

main.py

@@ -1,4 +1,4 @@
-import re 
+import logging
 import subprocess
 import os
 import datetime
@@ -11,12 +11,18 @@
 from src import settings
 from src import docker
 
+# Read config and setup logging
 config, global_labels = settings.read()
+logging.basicConfig(
+ level=config.loglevel,
+ format='%(asctime)s %(levelname)s %(message)s'
+)
+logging.info("Starting backup service")
+
+# Connecting to docker API
 docker_client = docker.get_client()
 own_container = docker.get_own_container(docker_client)
-
-if config.verbose:
- print(f"VERBOSE: Own Container ID: {own_container.id}")
+logging.debug(f"Own Container ID: {own_container.id}")
 
 while True:
  containers = docker_client.containers.list(
@@ -27,29 +33,28 @@
 
  if len(containers):
  successful_containers = 0
- print(f"Starting backup cycle with {len(containers)} container(s)..")
+ logging.info(f"Starting backup cycle with {len(containers)} container(s)..")
 
  network = docker_client.networks.create("docker-database-backup")
  network.connect(own_container.id)
 
  for i, container in enumerate(containers):
  database = Database(container, global_labels)
 
- print("[{}/{}] Processing container {} {} ({})".format(
+ logging.info("[{}/{}] Processing container {} {} ({})".format(
  i + 1, 
  len(containers), 
  container.short_id,
  container.name,
  database.type.name
  ))
 
- if config.verbose:
- print("VERBOSE: Login {}@host:{} using Password: {}".format(database.username, database.port, "YES" if len(database.password) > 0 else "NO"))
- if database.compress:
- print("VERBOSE: Compressing backup")
+ logging.debug("Login {}@host:{} using Password: {}".format(database.username, database.port, "YES" if len(database.password) > 0 else "NO"))
+ if database.compress:
+ logging.debug("Compressing backup")
 
  if database.type == DatabaseType.unknown:
- print("Cannot read database type. Please specify via label.")
+ logging.info("Cannot read database type. Please specify via label.")
 
  network.connect(container, aliases = ["database-backup-target"])
  outFile = "/dump/{}.sql".format(container.name)
@@ -94,8 +99,8 @@
  network.disconnect(container)
 
  if error_code > 0:
- print(f"FAILED. Return Code: {error_code}; Error Output:")
- print(f"{error_text}")
+ logging.error(f"FAILED. Return Code: {error_code}; Error Output:")
+ logging.error(f"{error_text}")
  else:
  if (os.path.exists(outFile)):
  uncompressed_size = os.path.getsize(outFile)
@@ -111,17 +116,17 @@
  os.chown(outFile, config.dump_uid, config.dump_gid) # pylint: disable=maybe-no-member
 
  successful_containers += 1
- print("SUCCESS. Size: {}{}".format(humanize.naturalsize(uncompressed_size), " (" + humanize.naturalsize(compressed_size) + " compressed)" if database.compress else ""))
+ logging.info("SUCCESS. Size: {}{}".format(humanize.naturalsize(uncompressed_size), " (" + humanize.naturalsize(compressed_size) + " compressed)" if database.compress else ""))
 
  network.disconnect(own_container.id)
  network.remove()
- print(f"Finished backup cycle. {successful_containers}/{len(containers)} successful.")
+ logging.info(f"Finished backup cycle. {successful_containers}/{len(containers)} successful.")
  else:
- print("No databases to backup")
+ logging.info("No databases to backup")
 
  if config.interval > 0:
  nextRun = datetime.datetime.now() + datetime.timedelta(seconds=config.interval)
- print("Scheduled next run at {}..".format(nextRun.strftime("%Y-%m-%d %H:%M:%S")))
+ logging.info("Scheduled next run at {}..".format(nextRun.strftime("%Y-%m-%d %H:%M:%S")))
 
  time.sleep(config.interval)
  else:

src/docker.py

@@ -1,3 +1,4 @@
+import logging
 import os
 import sys
 
@@ -8,7 +9,7 @@
 
 def get_client():
  if not os.path.exists(DOCKER_SOCK):
- print(f"ERROR: Docker Socket not found. Socket file must be created at {DOCKER_SOCK}")
+ logging.error(f"Docker Socket not found. Socket file must be created at {DOCKER_SOCK}")
  sys.exit(1)
 
  return docker.from_env()
@@ -22,10 +23,10 @@ def get_own_container(docker_client):
  )
 
  if len(containers) == 0:
- print("ERROR: Cannot determine own container id!")
+ logging.error("Cannot determine own container id!")
  sys.exit(1)
  elif len(containers) > 1:
- print("ERROR: Detected another instance of this image. Running multiple instances of the backup service is currently not supported!")
+ logging.error("Detected another instance of this image. Running multiple instances of the backup service is currently not supported!")
  sys.exit(1)
 
  return containers[0]

src/settings.py

@@ -1,3 +1,4 @@
+import logging
 import os
 import distutils.util
 
@@ -26,6 +27,7 @@ def __init__(self, values):
  raise AttributeError("Interval must be positive")
 
  self.verbose = distutils.util.strtobool(values["verbose"])
+ self.loglevel = logging.DEBUG if self.verbose else logging.INFO
 
  self.dump_uid = int(values["dump_uid"])
  self.dump_gid = int(values["dump_gid"])