Improve str2dict key validation to avoid wrong keys

This commit adds valid_keys and required_keys to str2dict
and define a new function which can be used as argparse type
validator.

By this function, we can declare what fields are valid and what
fields are required for dictionary option in option definition.

Change-Id: Ib7b233e082c15d0bd6e16a754b8acad52e413986
Closes-Bug: #1102897

1 files changed, 34 insertions, 2 deletions

diff --git a/neutronclient/common/utils.py b/neutronclient/common/utils.py
index 4f19dac..47610e6 100644
--- a/neutronclient/common/utils.py
+++ b/neutronclient/common/utils.py
@@ -18,6 +18,7 @@
 """Utilities and helper functions."""
 
 import argparse
+import functools
 import logging
 import netaddr
 import os
@@ -108,10 +109,21 @@ def str2bool(strbool):
     return strbool.lower() == 'true'
 
 
-def str2dict(strdict):
+def str2dict(strdict, required_keys=None, optional_keys=None):
     """Convert key1=value1,key2=value2,... string into dictionary.
 
-    :param strdict: key1=value1,key2=value2
+    :param strdict: string in the form of key1=value1,key2=value2
+    :param required_keys: list of required keys. All keys in this list must be
+                       specified. Otherwise ArgumentTypeError will be raised.
+                       If this parameter is unspecified, no required key check
+                       will be done.
+    :param optional_keys: list of optional keys.
+                       This parameter is used for valid key check.
+                       When at least one of required_keys and optional_keys,
+                       a key must be a member of either of required_keys or
+                       optional_keys. Otherwise, ArgumentTypeError will be
+                       raised. When both required_keys and optional_keys are
+                       unspecified, no valid key check will be done.
     """
     result = {}
     if strdict:
@@ -121,9 +133,29 @@ def str2dict(strdict):
                 msg = _("invalid key-value '%s', expected format: key=value")
                 raise argparse.ArgumentTypeError(msg % kv)
             result[key] = value
+    valid_keys = set(required_keys or []) | set(optional_keys or [])
+    if valid_keys:
+        invalid_keys = [k for k in result if k not in valid_keys]
+        if invalid_keys:
+            msg = _("Invalid key(s) '%(invalid_keys)s' specified. "
+                    "Valid key(s): '%(valid_keys)s'.")
+            raise argparse.ArgumentTypeError(
+                msg % {'invalid_keys': ', '.join(sorted(invalid_keys)),
+                       'valid_keys': ', '.join(sorted(valid_keys))})
+    if required_keys:
+        not_found_keys = [k for k in required_keys if k not in result]
+        if not_found_keys:
+            msg = _("Required key(s) '%s' not specified.")
+            raise argparse.ArgumentTypeError(msg % ', '.join(not_found_keys))
     return result
 
 
+def str2dict_type(optional_keys=None, required_keys=None):
+    return functools.partial(str2dict,
+                             optional_keys=optional_keys,
+                             required_keys=required_keys)
+
+
 def http_log_req(_logger, args, kwargs):
     if not _logger.isEnabledFor(logging.DEBUG):
         return