Add password-file CLI argument

 - By using a simple line-in-file search we don't have to parse
   the Bareos configuration format and can use any key-value (key=value) file

check_bareos.py

@@ -58,6 +58,30 @@
 }
 
 
+def read_password_from_file(fp):
+    """
+    Tries to read a password from the given file
+    This allows to extract the password from the Bareos configuration
+    or from any other file that contains 'Password = secretpassword'
+    """
+    l = []
+    pwd = None
+    # Extract the password from the given file
+    with open(fp, encoding='utf-8') as pwfile:
+        for line in pwfile:
+            line = line.strip()
+            if 'Password' in line:
+                l = line.split()
+    # Validate that we got a password
+    try:
+        pwd = l[2]
+    except IndexError:
+        pass
+    if not pwd:
+        raise ValueError('No password found in', fp)
+
+    return pwd
+
 def check_threshold(value, warning, critical):
     # checks a value against warning and critical thresholds
     if critical is not None:
@@ -572,9 +596,15 @@ def environ_or_required(key):
     parser = argparse.ArgumentParser(description='Check Plugin for Bareos Backup Status')
     group = parser.add_argument_group()
     group.add_argument('-U', '--user', dest='user', action='store', required=True, help='user name for the database connections')
-    group.add_argument('-p', '--password', dest='password', action='store',
-                       **environ_or_required('CHECK_BAREOS_DATABASE_PASSWORD'),
-                       help='password for the database connections')
+
+    password_group = group.add_mutually_exclusive_group()
+
+    password_group.add_argument('-p', '--password', dest='password', action='store',
+                                **environ_or_required('CHECK_BAREOS_DATABASE_PASSWORD'),
+                                help='password for the database connections')
+    password_group.add_argument('--password-file', dest='password_file', action='store',
+                                default='/etc/bareos/bareos-dir.conf',
+                                help='path to a password file. Can be the bareos-dir.conf')
 
     group.add_argument('-H', '--Host', dest='host', action='store', help='database host', default="127.0.0.1")
     group.add_argument('-P', '--port', dest='port', action='store', help='database port', default=5432, type=int)
@@ -718,6 +748,10 @@ def checkStatus(args):
 if __name__ == '__main__': # pragma: no cover
     try:
         ARGS = commandline(sys.argv[1:])
+
+        if ARGS.password_file and not ARGS.password:
+            ARGS.password = read_password_from_file(ARGS.password_file)
+
         ARGS.func(ARGS)
     except SystemExit:
         # Re-throw the exception

contrib/bareos-dir.conf

@@ -0,0 +1,4 @@
+Director {
+  Name = bareos-dir
+  Password = secretpassword
+}

test_check_bareos.py

@@ -9,6 +9,7 @@
 
 
 from check_bareos import commandline
+from check_bareos import read_password_from_file
 from check_bareos import createBackupKindString
 from check_bareos import createFactor
 from check_bareos import printNagiosOutput
@@ -102,6 +103,13 @@ def test_printNagiosOutput(self, mock_print):
             actual = printNagiosOutput({'returnCode': 1, 'returnMessage': "bar", 'performanceData': 'foo'})
         self.assertEqual(sysexit.exception.code, 1)
 
+    def test_read_password_from_file(self):
+        actual = read_password_from_file('contrib/bareos-dir.conf')
+        expected = 'secretpassword'
+        self.assertEqual(actual, expected)
+
+        with self.assertRaises(FileNotFoundError) as sysexit:
+            read_password_from_file('contrib/nosuch')
 
 class SQLTesting(unittest.TestCase):