Add informative error message for 404 responses

When the nsx backend returns 404 not found with error code 202,
the error message includes the exact resource that is missing.
Adding this information to the exception can help the customer to
understand the problem.

Change-Id: I5b34235ff56eb87b430c974ca43a696b6e505d0c

vmware_nsxlib/tests/unit/v3/test_cert.py

@@ -67,7 +67,7 @@ class NsxV3ClientCertificateTestCase(nsxlib_testcase.NsxClientTestCase):
             jsonutils.dumps({'httpStatus': 'go away',
                              'error_code': error_code,
                              'module_name': 'never mind',
-                             'error message': 'bad luck'}))
+                             'error_message': 'bad luck'}))
 
     def _get_mocked_trust(self, action, cert_pem):
 

vmware_nsxlib/tests/unit/v3/test_client.py

@@ -14,6 +14,7 @@
 #    under the License.
 #
 import copy
+import requests
 
 from oslo_log import log
 from oslo_serialization import jsonutils
@@ -228,9 +229,15 @@ class NsxV3RESTClientTestCase(nsxlib_testcase.NsxClientTestCase):
 
     def test_client_validate_result(self):
 
-        def _verb_response_code(http_verb, status_code):
+        def _verb_response_code(http_verb, status_code, error_code=None):
+            content = None
+            if error_code:
+                content = jsonutils.dumps({'httpStatus': 'dummy',
+                                           'error_code': error_code,
+                                           'module_name': 'dummy',
+                                           'error_message': 'bad'})
             response = mocks.MockRequestsResponse(
-                status_code, None)
+                status_code, content)
 
             client_api = self.new_mocked_client(
                 client.RESTClient, mock_validate=False,
@@ -244,7 +251,16 @@ class NsxV3RESTClientTestCase(nsxlib_testcase.NsxClientTestCase):
                 _verb_response_code(verb, code)
             self.assertRaises(
                 nsxlib_exc.ManagerError,
-                _verb_response_code, verb, 500)
+                _verb_response_code, verb,
+                requests.codes.INTERNAL_SERVER_ERROR)
+            self.assertRaises(
+                nsxlib_exc.ResourceNotFound,
+                _verb_response_code, verb,
+                requests.codes.NOT_FOUND)
+            self.assertRaises(
+                nsxlib_exc.BackendResourceNotFound,
+                _verb_response_code, verb,
+                requests.codes.NOT_FOUND, 202)
 
 
 class NsxV3JSONClientTestCase(nsxlib_testcase.NsxClientTestCase):

vmware_nsxlib/v3/client.py

@@ -28,16 +28,21 @@ NULL_CURSOR_PREFIX = '0000'
 
 
 def http_error_to_exception(status_code, error_code):
-    errors = {requests.codes.NOT_FOUND: exceptions.ResourceNotFound,
-              requests.codes.PRECONDITION_FAILED: exceptions.StaleRevision,
-              requests.codes.INTERNAL_SERVER_ERROR:
-                  {'99': exceptions.ClientCertificateNotTrusted}}
+    errors = {
+        requests.codes.NOT_FOUND:
+            {'202': exceptions.BackendResourceNotFound,
+             'default': exceptions.ResourceNotFound},
+        requests.codes.PRECONDITION_FAILED: exceptions.StaleRevision,
+        requests.codes.INTERNAL_SERVER_ERROR:
+            {'99': exceptions.ClientCertificateNotTrusted}}
 
     if status_code in errors:
         if isinstance(errors[status_code], dict):
             # choose based on error code
-            if error_code in errors[status_code]:
-                return errors[status_code][error_code]
+            if error_code and str(error_code) in errors[status_code]:
+                return errors[status_code][str(error_code)]
+            elif 'default' in errors[status_code]:
+                return errors[status_code]['default']
         else:
             return errors[status_code]
 

vmware_nsxlib/v3/exceptions.py

@@ -83,6 +83,11 @@ class ResourceNotFound(ManagerError):
                 "%(operation)s")
 
 
+class BackendResourceNotFound(ResourceNotFound):
+    message = _("%(details)s On backend (%(manager)s) with Operation: "
+                "%(operation)s")
+
+
 class InvalidInput(ManagerError):
     message = _("%(operation)s failed: Invalid input %(arg_val)s "
                 "for %(arg_name)s")