Set a min and max on the connection_debug option

There is a set allowable minimum and maximum to the connection_debug
option of 0 and 100. The config option should enforce this.

Change-Id: Ica610ad8fc0875a8be1042f7daba5d0a0c1aad03

oslo_db/options.py

@@ -101,6 +101,7 @@ database_opts = [
                     'SQLAlchemy.'),
     cfg.IntOpt('connection_debug',
                default=0,
+               min=0, max=100,
                deprecated_opts=[cfg.DeprecatedOpt('sql_connection_debug',
                                                   group='DEFAULT')],
                help='Verbosity of SQL debugging information: 0=None, '

oslo_db/sqlalchemy/engines.py

@@ -93,7 +93,7 @@ def _setup_logging(connection_debug=0):
     """
     if connection_debug >= 0:
         logger = logging.getLogger('sqlalchemy.engine')
-        if connection_debug >= 100:
+        if connection_debug == 100:
             logger.setLevel(logging.DEBUG)
         elif connection_debug >= 50:
             logger.setLevel(logging.INFO)

releasenotes/notes/connection_debug_min_max-bf6d53d49be7ca52.yaml

@@ -0,0 +1,7 @@
+---
+upgrade:
+  - The allowed values for the ``connection_debug`` option are now restricted to
+    the range between 0 and 100 (inclusive). Previously a number lower than 0
+    or higher than 100 could be given without error. But now, a
+    ``ConfigFileValueError`` will be raised when the option value is outside this
+    range.