Consistent way to set details for Error instances

This fixes and cleans up (making it consistent) how error
instances set their details value. The base class RESTError
will set the details value; all subclasses should call their
parent's __init__().

Unit tests were added to test that the Error instances are
initialized correctly.

Change-Id: I2390fa0012f8e4e6d73cbfb188f1733dfe85e65a
Closes-Bug: #1408817

2 files changed, 141 insertions, 29 deletions

diff --git a/ironic_python_agent/errors.py b/ironic_python_agent/errors.py
index 0b46465f..6058d191 100644
--- a/ironic_python_agent/errors.py
+++ b/ironic_python_agent/errors.py
@@ -22,10 +22,12 @@ class RESTError(Exception, encoding.Serializable):
     status_code = 500
     serializable_fields = ('type', 'code', 'message', 'details')
 
-    def __init__(self, *args, **kwargs):
+    def __init__(self, details=None, *args, **kwargs):
         super(RESTError, self).__init__(*args, **kwargs)
         self.type = self.__class__.__name__
         self.code = self.status_code
+        if details:
+            self.details = details
 
 
 class InvalidContentError(RESTError):
@@ -37,7 +39,7 @@ class InvalidContentError(RESTError):
     status_code = 400
 
     def __init__(self, details):
-        self.details = details
+        super(InvalidContentError, self).__init__(details)
 
 
 class NotFound(RESTError):
@@ -56,8 +58,7 @@ class CommandExecutionError(RESTError):
     message = 'Command execution failed'
 
     def __init__(self, details):
-        super(CommandExecutionError, self).__init__()
-        self.details = details
+        super(CommandExecutionError, self).__init__(details)
 
 
 class InvalidCommandError(InvalidContentError):
@@ -82,7 +83,6 @@ class RequestedObjectNotFoundError(NotFound):
     def __init__(self, type_descr, obj_id):
         details = '{0} with id {1} not found.'.format(type_descr, obj_id)
         super(RequestedObjectNotFoundError, self).__init__(details)
-        self.details = details
 
 
 class IronicAPIError(RESTError):
@@ -92,7 +92,6 @@ class IronicAPIError(RESTError):
 
     def __init__(self, details):
         super(IronicAPIError, self).__init__(details)
-        self.details = details
 
 
 class HeartbeatError(IronicAPIError):
@@ -139,8 +138,8 @@ class ImageDownloadError(RESTError):
     message = 'Error downloading image.'
 
     def __init__(self, image_id):
-        super(ImageDownloadError, self).__init__()
-        self.details = 'Could not download image with id {0}.'.format(image_id)
+        details = 'Could not download image with id {0}.'.format(image_id)
+        super(ImageDownloadError, self).__init__(details)
 
 
 class ImageChecksumError(RESTError):
@@ -149,9 +148,9 @@ class ImageChecksumError(RESTError):
     message = 'Error verifying image checksum.'
 
     def __init__(self, image_id):
-        super(ImageChecksumError, self).__init__()
-        self.details = 'Image with id {0} failed to verify against checksum.'
-        self.details = self.details.format(image_id)
+        details = 'Image with id {0} failed to verify against checksum.'
+        details = details.format(image_id)
+        super(ImageChecksumError, self).__init__(details)
 
 
 class ImageWriteError(RESTError):
@@ -160,10 +159,10 @@ class ImageWriteError(RESTError):
     message = 'Error writing image to device.'
 
     def __init__(self, device, exit_code, stdout, stderr):
-        super(ImageWriteError, self).__init__()
-        self.details = ('Writing image to device {0} failed with exit code '
-                        '{1}. stdout: {2}. stderr: {3}')
-        self.details = self.details.format(device, exit_code, stdout, stderr)
+        details = ('Writing image to device {0} failed with exit code '
+                   '{1}. stdout: {2}. stderr: {3}')
+        details = details.format(device, exit_code, stdout, stderr)
+        super(ImageWriteError, self).__init__(details)
 
 
 class ConfigDriveTooLargeError(RESTError):
@@ -174,7 +173,6 @@ class ConfigDriveTooLargeError(RESTError):
         details = ('Configdrive at {0} has size {1}, which is larger than '
                    'the intended partition.').format(filename, filesize)
         super(ConfigDriveTooLargeError, self).__init__(details)
-        self.details = details
 
 
 class ConfigDriveWriteError(RESTError):
@@ -189,7 +187,6 @@ class ConfigDriveWriteError(RESTError):
                    '{1}. stdout: {2}. stderr: {3}.')
         details = details.format(device, exit_code, stdout, stderr)
         super(ConfigDriveWriteError, self).__init__(details)
-        self.details = details
 
 
 class SystemRebootError(RESTError):
@@ -198,10 +195,10 @@ class SystemRebootError(RESTError):
     message = 'Error rebooting system.'
 
     def __init__(self, exit_code, stdout, stderr):
-        super(SystemRebootError, self).__init__()
-        self.details = ('Reboot script failed with exit code {0}. stdout: '
-                        '{1}. stderr: {2}.')
-        self.details = self.details.format(exit_code, stdout, stderr)
+        details = ('Reboot script failed with exit code {0}. stdout: '
+                   '{1}. stderr: {2}.')
+        details = details.format(exit_code, stdout, stderr)
+        super(SystemRebootError, self).__init__(details)
 
 
 class BlockDeviceEraseError(RESTError):
@@ -211,7 +208,6 @@ class BlockDeviceEraseError(RESTError):
 
     def __init__(self, details):
         super(BlockDeviceEraseError, self).__init__(details)
-        self.details = details
 
 
 class BlockDeviceError(RESTError):
@@ -220,7 +216,6 @@ class BlockDeviceError(RESTError):
 
     def __init__(self, details):
         super(BlockDeviceError, self).__init__(details)
-        self.details = details
 
 
 class VirtualMediaBootError(RESTError):
@@ -231,7 +226,6 @@ class VirtualMediaBootError(RESTError):
 
     def __init__(self, details):
         super(VirtualMediaBootError, self).__init__(details)
-        self.details = details
 
 
 class ExtensionError(Exception):
@@ -267,8 +261,8 @@ class HardwareManagerMethodNotFound(RESTError):
     message = msg + '.'
 
     def __init__(self, method):
-        self.details = (self.msg + ': "{0}".').format(method)
-        super(HardwareManagerMethodNotFound, self).__init__(self.details)
+        details = (self.msg + ': "{0}".').format(method)
+        super(HardwareManagerMethodNotFound, self).__init__(details)
 
 
 class IncompatibleHardwareMethodError(RESTError):
@@ -280,7 +274,7 @@ class IncompatibleHardwareMethodError(RESTError):
 
     def __init__(self, details=None):
         if details is not None:
-            self.details = details
+            details = details
         else:
-            self.details = self.message
-        super(IncompatibleHardwareMethodError, self).__init__(self.details)
+            details = self.message
+        super(IncompatibleHardwareMethodError, self).__init__(details)
diff --git a/ironic_python_agent/tests/errors.py b/ironic_python_agent/tests/errors.py
new file mode 100644
index 00000000..cc0c0da3
--- /dev/null
+++ b/ironic_python_agent/tests/errors.py
@@ -0,0 +1,118 @@
+#    Copyright (C) 2015 Yahoo! Inc. All Rights Reserved.
+#
+#    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.
+
+from oslotest import base as test_base
+
+from ironic_python_agent import errors
+
+DETAILS = 'details'
+SAME_CL_DETAILS = 'same_as_class_details'
+DIFF_CL_DETAILS = 'different_from_class_details'
+SAME_CL_MSG = 'same_as_class_message'
+SAME_DETAILS = 'same_as_DETAILS'
+
+
+class TestErrors(test_base.BaseTestCase):
+
+    def test_RESTError(self):
+        e = errors.RESTError()
+        d = e.serialize()
+
+        self.assertEqual("RESTError", e.type)
+        self.assertEqual(errors.RESTError.status_code, e.code)
+        self.assertEqual(errors.RESTError.message, e.message)
+        self.assertEqual(errors.RESTError.details, e.details)
+
+        self.assertEqual("RESTError", d['type'])
+        self.assertEqual(errors.RESTError.status_code, d['code'])
+        self.assertEqual(errors.RESTError.message, d['message'])
+        self.assertEqual(errors.RESTError.details, d['details'])
+
+    def test_RESTError_details(self):
+        e = errors.RESTError(DETAILS)
+        self.assertEqual("RESTError", e.type)
+        self.assertEqual(500, e.code)
+        self.assertEqual(errors.RESTError.message, e.message)
+        self.assertEqual(DETAILS, e.details)
+
+    def _test_class(self, obj, check_details):
+        """Test that the object is created correctly
+
+        :param obj: object to be tested
+        :param check_details: how to check the object's details value.
+                             One of SAME_CL_DETAILS, DIFF_CL_DETAILS,
+                             SAME_CL_MSG, SAME_DETAILS
+
+        """
+        obj_info = "object info = %s" % obj.__dict__
+        cls = obj.__class__
+        d = obj.serialize()
+
+        self.assertEqual(cls.__name__, obj.type, obj_info)
+        self.assertEqual(cls.status_code, obj.code, obj_info)
+        self.assertEqual(cls.message, obj.message, obj_info)
+
+        self.assertEqual(cls.__name__, d['type'], obj_info)
+        self.assertEqual(cls.status_code, d['code'], obj_info)
+        self.assertEqual(cls.message, d['message'], obj_info)
+        self.assertEqual(obj.details, d['details'], obj_info)
+
+        if check_details == SAME_CL_DETAILS:
+            self.assertEqual(cls.details, obj.details, obj_info)
+        elif check_details == DIFF_CL_DETAILS:
+            self.assertNotEqual(cls.details, obj.details, obj_info)
+        elif check_details == SAME_CL_MSG:
+            self.assertEqual(cls.message, obj.details, obj_info)
+        elif check_details == SAME_DETAILS:
+            self.assertEqual(DETAILS, obj.details, obj_info)
+        else:
+            self.fail("unexpected value for check_details: %(chk)s, %(info)s" %
+                      {'info': obj_info, 'chk': check_details})
+
+    def test_error_classes(self):
+        cases = [(errors.InvalidContentError(DETAILS), SAME_DETAILS),
+                 (errors.NotFound(), SAME_CL_DETAILS),
+                 (errors.CommandExecutionError(DETAILS), SAME_DETAILS),
+                 (errors.InvalidCommandError(DETAILS), SAME_DETAILS),
+                 (errors.InvalidCommandParamsError(DETAILS), SAME_DETAILS),
+                 (errors.RequestedObjectNotFoundError('type_descr', 'obj_id'),
+                  DIFF_CL_DETAILS),
+                 (errors.IronicAPIError(DETAILS), SAME_DETAILS),
+                 (errors.HeartbeatError(DETAILS), SAME_DETAILS),
+                 (errors.LookupNodeError(DETAILS), SAME_DETAILS),
+                 (errors.LookupAgentIPError(DETAILS), SAME_DETAILS),
+                 (errors.LookupAgentInterfaceError(DETAILS), SAME_DETAILS),
+                 (errors.ImageDownloadError('image_id'), DIFF_CL_DETAILS),
+                 (errors.ImageChecksumError('image_id'), DIFF_CL_DETAILS),
+                 (errors.ImageWriteError('device', 'exit_code', 'stdout',
+                                         'stderr'),
+                  DIFF_CL_DETAILS),
+                 (errors.ConfigDriveTooLargeError('filename', 'filesize'),
+                  DIFF_CL_DETAILS),
+                 (errors.ConfigDriveWriteError('device', 'exit_code', 'stdout',
+                                               'stderr'),
+                  DIFF_CL_DETAILS),
+                 (errors.SystemRebootError('exit_code', 'stdout', 'stderr'),
+                  DIFF_CL_DETAILS),
+                 (errors.BlockDeviceEraseError(DETAILS), SAME_DETAILS),
+                 (errors.BlockDeviceError(DETAILS), SAME_DETAILS),
+                 (errors.VirtualMediaBootError(DETAILS), SAME_DETAILS),
+                 (errors.HardwareManagerMethodNotFound('method'),
+                  DIFF_CL_DETAILS),
+                 (errors.IncompatibleHardwareMethodError(), SAME_CL_MSG),
+                 (errors.IncompatibleHardwareMethodError(DETAILS),
+                  SAME_DETAILS),
+                ]
+        for (obj, check_details) in cases:
+            self._test_class(obj, check_details)