Fixed healthcheck for classic (non Kubernetes) Docker (broken with default-ipv6 "::" listen ip) #89

Added multi-ip healthcheck support
Cleanup of logging inside container-scripts
Removed "nc" from containers

docker/healthcheck.py

@@ -0,0 +1,37 @@
+#!/usr/bin/python3 -u
+import os
+import sys
+import logging
+
+def do_check(logger):
+  import socket
+  listen_ip = os.environ.get('IP', '::').split()
+  listen_ip.insert(0, '127.0.0.1') # always try to connect to localhost first
+  listen_port = os.environ.get('PORT', '1688')
+  for ip in listen_ip:
+    try:
+      s = socket.socket(socket.AF_INET6 if ':' in ip else socket.AF_INET, socket.SOCK_STREAM)
+      s.settimeout(1) # 1 second timeout
+      address = ip if ':' in ip else (ip, int(listen_port))
+      logger.debug(f"Trying to connect to {address}...")
+      s.connect(address)
+      s.close()
+      return True
+    except:
+      pass
+  return False # no connection could be established
+
+
+if __name__ == '__main__':
+  log_level_bootstrap = log_level = os.getenv('LOGLEVEL', 'INFO')
+  if log_level_bootstrap == "MININFO":
+    log_level_bootstrap = "INFO"
+  loggersrv = logging.getLogger('healthcheck.py')
+  loggersrv.setLevel(log_level_bootstrap)
+  streamhandler = logging.StreamHandler(sys.stdout)
+  streamhandler.setLevel(log_level_bootstrap)
+  formatter = logging.Formatter(fmt='\x1b[94m%(asctime)s %(levelname)-8s %(message)s', datefmt='%a, %d %b %Y %H:%M:%S')
+  streamhandler.setFormatter(formatter)
+  loggersrv.addHandler(streamhandler)
+  
+  sys.exit(0 if do_check(loggersrv) else 1)