Add details to HttpException string

Without this change:

    400 Client Error: Bad Request

With this change, the much more useful:

    HttpException: 400 Client Error: Bad Request, Validation error: instance 'flavorRef' is a required property

Change-Id: Iaa63969e327532c02d72999efcbee42aa0d381d3

openstack/exceptions.py

@@ -16,6 +16,8 @@
 Exception definitions.
 """
 
+import six
+
 
 class SDKException(Exception):
     """The base exception class for all exceptions this library raises."""
@@ -62,6 +64,15 @@ class HttpException(SDKException):
         super(HttpException, self).__init__(message)
         self.details = details
 
+    def __unicode__(self):
+        msg = self.__class__.__name__ + ": " + self.message
+        if self.details:
+            msg += ", " + six.text_type(self.details)
+        return msg
+
+    def __str__(self):
+        return self.__unicode__()
+
 
 class MethodNotSupported(SDKException):
     """The resource does not support this operation type."""

openstack/tests/test_transport.py

@@ -15,6 +15,7 @@ import logging
 
 import fixtures
 import httpretty
+import mock
 import requests
 import six
 
@@ -634,3 +635,18 @@ class TestTransportRedirects(base.TestTransportBase):
         for r, s in zip(req_resp.history, resp.history):
             self.assertEqual(s.url, r.url)
             self.assertEqual(s.status_code, r.status_code)
+
+    def test_parse_error_response(self):
+        xport = transport.Transport(redirect=True)
+        resp = mock.Mock()
+        resp.json = mock.Mock()
+        resp.json.return_value = {"badRequest": {"message": "Not defined"}}
+        self.assertEqual("Not defined", xport._parse_error_response(resp))
+        resp.json.return_value = {"message": {"response": "Not Allowed"}}
+        self.assertEqual("Not Allowed", xport._parse_error_response(resp))
+        resp.json.return_value = {"itemNotFound": {"message": "Not found"}}
+        self.assertEqual("Not found", xport._parse_error_response(resp))
+        resp.json.return_value = {"instanceFault": {"message": "Wot?"}}
+        self.assertEqual("Wot?", xport._parse_error_response(resp))
+        resp.json.return_value = {"QuantumError": "Network error"}
+        self.assertEqual("Network error", xport._parse_error_response(resp))

openstack/transport.py

@@ -151,7 +151,8 @@ class Transport(requests.Session):
         try:
             resp.raise_for_status()
         except requests.RequestException as e:
-            raise exceptions.HttpException(six.text_type(e), details=resp.text)
+            raise exceptions.HttpException(six.text_type(e),
+                                           self._parse_error_response(resp))
         if accept == JSON:
             try:
                 resp.body = resp.json()
@@ -202,6 +203,28 @@ class Transport(requests.Session):
 
         return resp
 
+    def _parse_error_response(self, resp):
+        try:
+            jresp = resp.json()
+            # compute
+            if "badRequest" in jresp and "message" in jresp["badRequest"]:
+                return jresp["badRequest"]["message"]
+            # identity
+            if "message" in jresp and "response" in jresp["message"]:
+                return jresp["message"]["response"]
+            # network
+            if "QuantumError" in jresp:
+                return jresp["QuantumError"]
+            # database
+            if "itemNotFound" in jresp and "message" in jresp["itemNotFound"]:
+                return jresp["itemNotFound"]["message"]
+            if "instanceFault" in jresp:
+                if "message" in jresp["instanceFault"]:
+                    return jresp["instanceFault"]["message"]
+        except ValueError:
+            pass
+        return resp.text
+
     def _log_request(self, method, url, **kwargs):
         if not _logger.isEnabledFor(logging.DEBUG):
             return