[1889] use cwd as data_path in cfgmgr if config_file is given

Depending on whether config_file is specified, use either the builtin default or os.getcwd() for the data path (so that you can use relative config file names. If an absolute config file is given, data path is ignored).

Also added an info log message specifying which file cfgmgr ends up using.

src/bin/cfgmgr/b10-cfgmgr.py.in

@@ -44,11 +44,11 @@ def parse_options(args=sys.argv[1:], Parser=OptionParser):
     parser = Parser()
     parser.add_option("-p", "--data-path", dest="data_path",
                       help="Directory to search for configuration files " +
-                      "(default=" + DATA_PATH + ")", default=DATA_PATH)
+                      "(default=" + DATA_PATH + ")", default=None)
     parser.add_option("-c", "--config-filename", dest="config_file",
                       help="Configuration database filename " +
                       "(default=" + DEFAULT_CONFIG_FILE + ")",
-                      default=DEFAULT_CONFIG_FILE)
+                      default=None)
     parser.add_option("--clear-config", action="store_true",
                       dest="clear_config", default=False,
                       help="Back up the configuration file and start with " +
@@ -85,12 +85,37 @@ def load_plugins(path, cm):
         # Restore the search path
         sys.path = sys.path[1:]
 
+
+def determine_path_and_file(data_path_option, config_file_option):
+    """Given the data path and config file as specified on the command line
+       (or not specified, as may be the case), determine the full path and
+       file to use when starting the config manager;
+       - if neither are given, use defaults
+       - if both are given, use both
+       - if only data path is given, use default file in that path
+       - if only file is given, use cwd() + file (if file happens to
+         be an absolute file name, path will be ignored)
+       Arguments are either a string, or None.
+       Returns a tuple containing (result_path, result_file).
+    """
+    data_path = data_path_option
+    config_file = config_file_option
+    if config_file is None:
+        config_file = DEFAULT_CONFIG_FILE
+        if data_path is None:
+            data_path = DATA_PATH
+    else:
+        if data_path is None:
+            data_path = os.getcwd()
+    return (data_path, config_file)
+
 def main():
     options = parse_options()
     global cm
     try:
-        cm = ConfigManager(options.data_path, options.config_file,
-                           None, options.clear_config)
+        (data_path, config_file) = determine_path_and_file(options.data_path,
+                                                           options.config_file)
+        cm = ConfigManager(data_path, config_file, None, options.clear_config)
         signal.signal(signal.SIGINT, signal_handler)
         signal.signal(signal.SIGTERM, signal_handler)
         cm.read_config()

src/bin/cfgmgr/tests/b10-cfgmgr_test.py.in

@@ -141,8 +141,8 @@ class TestParseArgs(unittest.TestCase):
         # Pass it empty array, not our arguments
         b = __import__("b10-cfgmgr")
         parsed = b.parse_options([], TestOptParser)
-        self.assertEqual(b.DATA_PATH, parsed.data_path)
-        self.assertEqual(b.DEFAULT_CONFIG_FILE, parsed.config_file)
+        self.assertEqual(None, parsed.data_path)
+        self.assertEqual(None, parsed.config_file)
 
     def test_wrong_args(self):
         """
@@ -168,10 +168,10 @@ class TestParseArgs(unittest.TestCase):
         b = __import__("b10-cfgmgr")
         parsed = b.parse_options(['--data-path=/path'], TestOptParser)
         self.assertEqual('/path', parsed.data_path)
-        self.assertEqual(b.DEFAULT_CONFIG_FILE, parsed.config_file)
+        self.assertEqual(None, parsed.config_file)
         parsed = b.parse_options(['-p', '/path'], TestOptParser)
         self.assertEqual('/path', parsed.data_path)
-        self.assertEqual(b.DEFAULT_CONFIG_FILE, parsed.config_file)
+        self.assertEqual(None, parsed.config_file)
         self.assertRaises(OptsError, b.parse_options, ['-p'], TestOptParser)
         self.assertRaises(OptsError, b.parse_options, ['--data-path'],
                           TestOptParser)
@@ -183,15 +183,26 @@ class TestParseArgs(unittest.TestCase):
         b = __import__("b10-cfgmgr")
         parsed = b.parse_options(['--config-filename=filename'],
                                  TestOptParser)
-        self.assertEqual(b.DATA_PATH, parsed.data_path)
+        self.assertEqual(None, parsed.data_path)
         self.assertEqual("filename", parsed.config_file)
         parsed = b.parse_options(['-c', 'filename'], TestOptParser)
-        self.assertEqual(b.DATA_PATH, parsed.data_path)
+        self.assertEqual(None, parsed.data_path)
         self.assertEqual("filename", parsed.config_file)
         self.assertRaises(OptsError, b.parse_options, ['-c'], TestOptParser)
         self.assertRaises(OptsError, b.parse_options, ['--config-filename'],
                           TestOptParser)
 
+    def test_determine_path_and_file(self):
+        b = __import__("b10-cfgmgr")
+        self.assertEqual((b.DATA_PATH, b.DEFAULT_CONFIG_FILE),
+                         b.determine_path_and_file(None, None))
+        self.assertEqual(("/foo", b.DEFAULT_CONFIG_FILE),
+                         b.determine_path_and_file("/foo", None))
+        self.assertEqual((os.getcwd(), "file.config"),
+                         b.determine_path_and_file(None, "file.config"))
+        self.assertEqual(("/foo", "bar"),
+                         b.determine_path_and_file("/foo", "bar"))
+
     def test_clear_config(self):
         b = __import__("b10-cfgmgr")
         parsed = b.parse_options([], TestOptParser)

src/lib/python/isc/config/cfgmgr.py

@@ -81,6 +81,7 @@ class ConfigManagerData:
            and stop loading the system.
            """
         config = ConfigManagerData(data_path, file_name)
+        logger.info(CFGMGR_CONFIG_FILE, config.db_filename)
         file = None
         try:
             file = open(config.db_filename, 'r')

src/lib/python/isc/config/cfgmgr_messages.mes

@@ -31,6 +31,10 @@ assumed to have failed, and will not be stored.
 The configuration manager daemon was unable to connect to the messaging
 system. The most likely cause is that msgq is not running.
 
+% CFGMGR_CONFIG_FILE Configuration manager starting with configuration file: %1
+The configuration manager is starting, reading and saving the configuration
+settings to the shown file.
+
 % CFGMGR_DATA_READ_ERROR error reading configuration database from disk: %1
 There was a problem reading the persistent configuration data as stored
 on disk. The file may be corrupted, or it is of a version from where