Read options from config file

Set a standardized configuration file location and read options from
there.  Allow for specifiying alternate location on command line.
Options can still be specified on the command line, and any command line
options take priority over those given in the configuration file.

1 files changed, 41 insertions, 23 deletions

diff --git a/client/client.py b/client/client.py
index b2429b6..1c7e155 100755
--- a/client/client.py
+++ b/client/client.py
@@ -4,6 +4,7 @@ import socket
 import time
 import argparse
 import sys
+import os
 
 HEADER_LENGTH = 64
 KEY_LENGTH = 64
@@ -11,6 +12,7 @@ DISCONNECT_LENGTH = ACK_LENGTH = 3
 ACK_MESSAGE = "ACK"
 DISCONNECT_MESSAGE = "BYE"
 FORMAT = "utf-8"
+import configparser
 
 def parse_arguments():
     parser = argparse.ArgumentParser()
@@ -18,7 +20,7 @@ def parse_arguments():
     parser.add_argument("--port",type=int,help="Port to connect to")
     parser.add_argument("--config",type=str,help="Path to config file",\
                         default="/etc/mfa/mfa.conf")
-    parser.add_argument("--key",type=str,help="Client connection key",required=True)
+    parser.add_argument("--key",type=str,help="Client connection key")
     return parser.parse_args()
 
 def prompt_user(prompt):
@@ -53,32 +55,48 @@ def init_connection(mfa_server, client_port, client_key):
 
 
 def read_config(config_file):
-    # Read config file for server and port info
-    # Return tuple (server,port)
-    server = ""
-    port = 0
-    with open(config_file) as conf:
-        line = None
-        while line != "":
-            line = conf.readline()
-            if line.startswith("server ="):
-                server = line.split("=")[1].strip()
-            if line.startswith("port ="):
-                port = int(line.split("=")[1].strip())
-    return (server,port)
+    parser = configparser.ConfigParser(inline_comment_prefixes="#")
+    parser.read(config_file)
+    return parser
+
+
+def get_vars(args,confparser):
+    if not os.path.exists(args.config):
+        print("Unable to open config file")
+        sys.exit(1)
+
+    server = None
+    port = None
+    key = None
+
+    # Set values from config file first
+    if confparser.has_section("client"):
+        server = confparser.get("client","server",fallback=None) 
+        port = confparser.get("client","port",fallback=None) 
+        key = confparser.get("client","key",fallback=None)
+        
+    # Let command line args overwrite any values
+    if args.server:
+        server = args.server
+    if args.port:
+        port = args.port
+    if args.key:
+        key = args.key
+
+    # Exit if any value is null
+    if None in [server,port,key]:
+        print("error: one or more items unspecified")
+        sys.exit(1)
+
+    return server,port,key
+
 
 def main():
     # Get arguments, exit if unable to connect
     args = parse_arguments()
-    client_key = args.key
-
-    # Read server and port from config file but allow command line options
-    # to override those settings
-    mfa_server, client_port = read_config(args.config)
-    if args.server != None:
-        mfa_server = args.server
-    if args.port != None:
-        client_port = args.port
+    confparser = read_config(args.config)
+
+    mfa_server,client_port,client_key = get_vars(args,confparser)
 
     # Exit if invalid key is provided
     if len(client_key) != KEY_LENGTH: