Use exception to message config errors

rcon/config.py

@@ -7,9 +7,10 @@ from getpass import getpass
 from logging import getLogger
 from os import getenv, name
 from pathlib import Path
-from sys import exit    # pylint: disable=W0622
 from typing import Iterable, NamedTuple, Optional, Union
 
+from rcon.exceptions import ConfigReadError
+
 
 __all__ = ['CONFIG_FILES', 'LOG_FORMAT', 'SERVERS', 'Config', 'from_args']
 
@@ -92,7 +93,7 @@ def from_args(args: Namespace) -> Config:
             host, port, passwd = SERVERS[args.server]
         except KeyError:
             LOGGER.error('No such server: %s.', args.server)
-            exit(2)
+            raise ConfigReadError(2)
 
     if passwd is None:
         try:
@@ -100,6 +101,6 @@ def from_args(args: Namespace) -> Config:
         except (KeyboardInterrupt, EOFError):
             print()
             LOGGER.error('Aborted by user.')
-            exit(1)
+            raise ConfigReadError(1)
 
     return Config(host, port, passwd)

rcon/exceptions.py

@@ -1,6 +1,14 @@
 """RCON exceptions."""
 
-__all__ = ['RequestIdMismatch', 'WrongPassword']
+__all__ = ['ConfigReadError', 'RequestIdMismatch', 'WrongPassword']
+
+
+class ConfigReadError(Exception):
+    """Indicates an error while reading the configuration."""
+
+    def __init__(self, exit_code: int):
+        super().__init__()
+        self.exit_code = exit_code
 
 
 class RequestIdMismatch(Exception):

rcon/rconclt.py

@@ -7,6 +7,7 @@ from pathlib import Path
 from rcon.client import Client
 from rcon.config import CONFIG_FILES, LOG_FORMAT, from_args
 from rcon.errorhandler import ErrorHandler
+from rcon.exceptions import ConfigReadError
 
 
 __all__ = ['main']
@@ -39,12 +40,16 @@ def get_args() -> Namespace:
     return parser.parse_args()
 
 
-def main() -> None:
+def main() -> int:
     """Runs the RCON client."""
 
     args = get_args()
     basicConfig(format=LOG_FORMAT, level=DEBUG if args.debug else INFO)
-    host, port, passwd = from_args(args)
+
+    try:
+        host, port, passwd = from_args(args)
+    except ConfigReadError as cre:
+        return cre.exit_code
 
     with ErrorHandler(LOGGER):
         with Client(host, port, timeout=args.timeout) as client:
@@ -52,3 +57,4 @@ def main() -> None:
             text = client.run(args.command, *args.argument)
 
     print(text, flush=True)
+    return 0

rcon/rconshell.py

@@ -7,6 +7,7 @@ from pathlib import Path
 from rcon.config import CONFIG_FILES, LOG_FORMAT, from_args
 from rcon.console import PROMPT, rconcmd
 from rcon.errorhandler import ErrorHandler
+from rcon.exceptions import ConfigReadError
 from rcon.readline import CommandHistory
 
 
@@ -32,17 +33,22 @@ def get_args() -> Namespace:
     return parser.parse_args()
 
 
-def main() -> None:
+def main() -> int:
     """Runs the RCON shell."""
 
     args = get_args()
     basicConfig(level=INFO, format=LOG_FORMAT)
 
     if args.server:
-        host, port, passwd = from_args(args)
+        try:
+            host, port, passwd = from_args(args)
+        except ConfigReadError as cre:
+            return cre.exit_code
     else:
         host = port = passwd = None
 
     with ErrorHandler(LOGGER):
         with CommandHistory(LOGGER):
             rconcmd(host, port, passwd, prompt=args.prompt)
+
+    return 0