Simple config validator

This is a very basic config validator that just reads the provided
config file and compares it with the machine readable sample config
data from the config generator to find any options that are not
defined in the project. It will also warn about deprecated options
in use in the provided file.

Change-Id: I410b16ffcfb069140bd51dffaba7d56eada1a7e9

oslo_config/validator.py

@@ -0,0 +1,117 @@
+#!/usr/bin/env python
+# Copyright 2018 Red Hat, Inc.
+#
+#    Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.
+
+"""Configuration Validator
+
+Uses the sample config generator configuration file to retrieve a list of all
+the available options in a project, then compares it to what is configured in
+the provided file.  If there are any options set that are not defined in the
+project then it returns those errors.
+"""
+
+import logging
+import sys
+
+import pkg_resources
+
+from oslo_config import cfg
+from oslo_config import generator
+
+
+_validator_opts = [
+    cfg.MultiStrOpt(
+        'namespace',
+        required=True,
+        help='Option namespace under "oslo.config.opts" in which to query '
+             'for options.'),
+    cfg.StrOpt(
+        'input-file',
+        required=True,
+        help='Config file to validate.'),
+    cfg.BoolOpt(
+        'fatal-warnings',
+        default=False,
+        help='Report failure if any warnings are found.'),
+]
+
+
+def _register_cli_opts(conf):
+    """Register the formatter's CLI options with a ConfigOpts instance.
+
+    Note, this must be done before the ConfigOpts instance is called to parse
+    the configuration.
+
+    :param conf: a ConfigOpts instance
+    :raises: DuplicateOptError, ArgsAlreadyParsedError
+    """
+    conf.register_cli_opts(_validator_opts)
+
+
+def _validate_deprecated_opt(group, option, opt_data):
+    if group not in opt_data['deprecated_options']:
+        return False
+    name_data = [o['name'] for o in opt_data['deprecated_options'][group]]
+    name_data += [o.get('dest') for o in opt_data['deprecated_options'][group]]
+    return option in name_data
+
+
+def _validate_opt(group, option, opt_data):
+    if group not in opt_data['options']:
+        return False
+    name_data = [o['name'] for o in opt_data['options'][group]['opts']]
+    name_data += [o.get('dest') for o in opt_data['options'][group]['opts']]
+    return option in name_data
+
+
+def _validate(conf):
+    conf.register_opts(_validator_opts)
+    groups = generator._get_groups(generator._list_opts(conf.namespace))
+    opt_data = generator._generate_machine_readable_data(groups, conf)
+    sections = {}
+    parser = cfg.ConfigParser(conf.input_file, sections)
+    parser.parse()
+    warnings = False
+    errors = False
+    for section, options in sections.items():
+        for option in options:
+            if _validate_deprecated_opt(section, option, opt_data):
+                logging.warn('Deprecated opt %s/%s found', section, option)
+                warnings = True
+            elif not _validate_opt(section, option, opt_data):
+                logging.error('%s/%s not found', section, option)
+                errors = True
+    if errors or (warnings and conf.fatal_warnings):
+        return 1
+    return 0
+
+
+def main():
+    """The main function of oslo-config-validator."""
+    version = pkg_resources.get_distribution('oslo.config').version
+    logging.basicConfig(level=logging.WARN)
+    conf = cfg.ConfigOpts()
+    _register_cli_opts(conf)
+    try:
+        conf(sys.argv[1:], version=version)
+    except cfg.RequiredOptError:
+        conf.print_help()
+        if not sys.argv[1:]:
+            raise SystemExit
+        raise
+    return _validate(conf)
+
+
+if __name__ == '__main__':
+    sys.exit(main())

setup.cfg

@@ -30,6 +30,7 @@ setup-hooks =
 [entry_points]
 console_scripts =
     oslo-config-generator = oslo_config.generator:main
+    oslo-config-validator = oslo_config.validator:main
 oslo.config.opts =
     oslo.config = oslo_config._list_opts:list_opts