exclude precise metaquery in query field

We use metaquery as a parameter of db func, and valid keys include
db func parameters.

When we parse query filters, the metadata dict is stored as key named
metaquery in kwargs, and we store q.field=foo as key named foo in kwargs.
Then if q.field=metaquery, the kwargs will get the key metaquery but
its type is something, for i.e. string, but not dict. However the db
func expects metaquery to be a dict but gets a string, then 500 is returned

This patch returns a 400 error for such case, and removes 'metaquery'
from valid keys in error message to avoid misleading end user.

Change-Id: I430717e71a6586d63f267baee29bb71ef8c9eac1
Closes-Bug: #1426466

ceilometer/api/controllers/v2/utils.py

@@ -104,8 +104,6 @@ def validate_query(query, db_func, internal_keys=None,
     :param allow_timestamps: defines whether the timestamp-based constraint is
         applicable for this query or not
 
-    :returns: valid query keys the db_func supported
-
     :raises InvalidInput: if an operator is not supported for a given field
     :raises InvalidInput: if timestamp constraints are allowed, but
         search_offset was included without timestamp constraint
@@ -127,6 +125,7 @@ def validate_query(query, db_func, internal_keys=None,
         internal_keys += internal_timestamp_keys
         valid_keys += ['timestamp', 'search_offset']
     internal_keys.append('self')
+    internal_keys.append('metaquery')
     valid_keys = set(valid_keys) - set(internal_keys)
     translation = {'user_id': 'user',
                    'project_id': 'project',
@@ -168,7 +167,6 @@ def validate_query(query, db_func, internal_keys=None,
                 msg = ("unrecognized field in query: %s, "
                        "valid keys: %s") % (query, sorted(valid_keys))
                 raise wsme.exc.UnknownArgument(key, msg)
-    return valid_keys
 
 
 def _validate_timestamp_fields(query, field_name, operator_list,
@@ -214,9 +212,8 @@ def _validate_timestamp_fields(query, field_name, operator_list,
 
 def query_to_kwargs(query, db_func, internal_keys=None,
                     allow_timestamps=True):
-    internal_keys = internal_keys or []
-    valid_keys = validate_query(query, db_func, internal_keys=internal_keys,
-                                allow_timestamps=allow_timestamps)
+    validate_query(query, db_func, internal_keys=internal_keys,
+                   allow_timestamps=allow_timestamps)
     query = sanitize_query(query, db_func)
     translation = {'user_id': 'user',
                    'project_id': 'project',
@@ -247,7 +244,7 @@ def query_to_kwargs(query, db_func, internal_keys=None,
                     key = translation.get(i.field, i.field)
                     kwargs[key] = i.value
 
-    if metaquery and 'metaquery' in valid_keys:
+    if metaquery and 'metaquery' in inspect.getargspec(db_func)[0]:
         kwargs['metaquery'] = metaquery
     if stamp:
         kwargs.update(_get_query_timestamps(stamp))

ceilometer/tests/api/v2/test_list_meters_scenarios.py

@@ -374,6 +374,23 @@ class TestListMeters(v2.FunctionalTest,
             }
         }], data)
 
+    def test_list_with_field_metaquery(self):
+        def _helper(url):
+            resp = self.get_json(url,
+                                 q=[{'field':
+                                     'metaquery',
+                                     'op': 'eq',
+                                     'value': 'cow',
+                                     }],
+                                 expect_errors=True)
+            self.assertEqual(400, resp.status_code)
+            expected = ('Unknown argument: "metaquery": '
+                        'unrecognized field in query')
+            self.assertIn(expected, resp.json['error_message']['faultstring'])
+
+        _helper('/samples')
+        _helper('/meters/meter.test')
+
     def test_list_meters_metadata_query(self):
         data = self.get_json('/meters/meter.test',
                              q=[{'field': 'metadata.tag',

ceilometer/tests/api/v2/test_query.py

@@ -367,9 +367,8 @@ class TestQueryToKwArgs(tests_base.BaseTestCase):
         exc = self.assertRaises(
             wsme.exc.UnknownArgument,
             utils.query_to_kwargs, q, storage.SampleFilter.__init__)
-        valid_keys = ['message_id', 'metaquery', 'meter', 'project',
-                      'resource', 'search_offset', 'source', 'timestamp',
-                      'user']
+        valid_keys = ['message_id', 'meter', 'project', 'resource',
+                      'search_offset', 'source', 'timestamp', 'user']
         msg = ("unrecognized field in query: %s, "
                "valid keys: %s") % (q, valid_keys)
         expected_exc = wsme.exc.UnknownArgument('abc', msg)
@@ -382,8 +381,7 @@ class TestQueryToKwArgs(tests_base.BaseTestCase):
         exc = self.assertRaises(
             wsme.exc.UnknownArgument,
             utils.query_to_kwargs, q, storage_base.Connection.get_meters)
-        valid_keys = ['metaquery', 'pagination', 'project', 'resource',
-                      'source', 'user']
+        valid_keys = ['pagination', 'project', 'resource', 'source', 'user']
         msg = ("unrecognized field in query: %s, "
                "valid keys: %s") % (q, valid_keys)
         expected_exc = wsme.exc.UnknownArgument('abc', msg)
@@ -396,7 +394,7 @@ class TestQueryToKwArgs(tests_base.BaseTestCase):
         exc = self.assertRaises(
             wsme.exc.UnknownArgument,
             utils.query_to_kwargs, q, storage_base.Connection.get_resources)
-        valid_keys = ['metaquery', 'pagination', 'project', 'resource',
+        valid_keys = ['pagination', 'project', 'resource',
                       'search_offset', 'source', 'timestamp', 'user']
         msg = ("unrecognized field in query: %s, "
                "valid keys: %s") % (q, valid_keys)

ceilometer/tests/gabbi/gabbits/samples.yaml

@@ -74,7 +74,8 @@ tests:
       url: /v2/samples?q.field=harpoon&q.value=cow&q.op=eq
       status: 400
       response_strings:
-          - metaquery
+          - timestamp
+          - project
           - unrecognized field in query
 
     - name: list samples with metaquery field