check if port is available before anything else

server.py

@@ -14,6 +14,7 @@ from MyLogger import my_logger
 import argparse
 from MyLogger import logger
 from MyPSACC import MyPSACC
+from utils import is_port_in_use
 from web.app import start_app, save_config
 
 parser = argparse.ArgumentParser()
@@ -21,19 +22,21 @@ parser = argparse.ArgumentParser()
 
 def parse_args():
     parser = argparse.ArgumentParser()
-    parser.add_argument("-f", "--config", help="config file, default file: config.json", type=argparse.FileType('r'), default="config.json")
+    parser.add_argument("-f", "--config", help="config file, default file: config.json", type=argparse.FileType('r'),
+                        default="config.json")
     parser.add_argument("-c", "--charge-control", help="enable charge control, default charge_config.json",
                         const="charge_config.json", nargs='?', metavar='charge config file')
-    parser.add_argument("-d", "--debug", help="enable debug", const=10, default=20, nargs='?', metavar='Debug level number')
+    parser.add_argument("-d", "--debug", help="enable debug", const=10, default=20, nargs='?',
+                        metavar='Debug level number')
     parser.add_argument("-l", "--listen", help="change server listen address", default="127.0.0.1", metavar="IP")
     parser.add_argument("-p", "--port", help="change server listen port", default="5000")
     parser.add_argument("-r", "--record", help="save vehicle data to db", action='store_true')
-    parser.add_argument("-R", "--refresh", help="refresh vehicles status every x min",type=int)
+    parser.add_argument("-R", "--refresh", help="refresh vehicles status every x min", type=int)
     parser.add_argument("-m", "--mail", default=environ.get('USER_EMAIL', None), help="set the email address")
     parser.add_argument("-P", "--password", default=environ.get('USER_PASSWORD', None), help="set the password")
     parser.add_argument("--remote-disable", help="disable remote control", action='store_true')
     parser.add_argument("--offline", help="offline limited mode", action='store_true')
-    parser.add_argument("-b", "--base-path", help="base path for web app",default="/")
+    parser.add_argument("-b", "--base-path", help="base path for web app", default="/")
     parser.parse_args()
     return parser
 
@@ -44,10 +47,13 @@ if __name__ == "__main__":
     parser = parse_args()
     args = parser.parse_args()
     try:
-        args.debug=int(args.debug)
+        args.debug = int(args.debug)
     except ValueError:
         pass
     my_logger(handler_level=args.debug)
+    if is_port_in_use(args.listen, int(args.port)):
+        logger.error(" Address already in use")
+        exit(1)
     logger.info("server start")
     if args.config:
         config_name = args.config.name

utils.py

@@ -3,6 +3,7 @@ from functools import wraps
 from threading import Semaphore, Timer
 
 import requests
+import socket
 
 from MyLogger import logger
 
@@ -42,3 +43,8 @@ def rate_limit(limit, every):
         return wrapper
 
     return limit_decorator
+
+
+def is_port_in_use(ip, port):
+    with socket.socket(socket.AF_INET, socket.SOCK_STREAM) as s:
+        return s.connect_ex((ip, port)) == 0