Merge pull request #70 from coopernurse/role-delete-idempotent

Role delete idempotent

@@ -38,9 +38,11 @@ class Role(object):
 
     Path = '/kappa/'
 
-    def __init__(self, context, config):
+    def __init__(self, context, config, iam_client=None):
         self._context = context
         self._config = config
+        self._iam_client = iam_client
+        if not iam_client:
             self._iam_client = kappa.awsclient.create_client(
                 'iam', context.session)
         self._arn = None
@@ -52,28 +54,28 @@ class Role(object):
     @property
     def arn(self):
         if self._arn is None:
-            try:
-                response = self._iam_client.call(
-                    'get_role', RoleName=self.name)
-                LOG.debug(response)
-                self._arn = response['Role']['Arn']
-            except Exception:
+            role = self._get_role()
+            if role:
+                self._arn = role['Arn']
+            else:
                 LOG.debug('Unable to find ARN for role: %s', self.name)
         return self._arn
 
-    def _find_all_roles(self):
+    def _get_role(self):
         try:
-            response = self._iam_client.call('list_roles')
+            response = self._iam_client.call('get_role', RoleName=self.name)
+            if response and 'Role' in response:
+                response = response['Role']
+            return response
+        except ClientError as e:
+            if e.response['Error']['Code'] != 'NoSuchEntity':
+                LOG.exception('Error getting role')
         except Exception:
-            LOG.exception('Error listing roles')
-            response = {}
-        return response.get('Roles', list())
+            LOG.exception('Error getting role')
+        return None
 
     def exists(self):
-        for role in self._find_all_roles():
-            if role['RoleName'] == self.name:
-                return role
-        return None
+        return self._get_role() is not None
 
     def create(self):
         LOG.info('creating role %s', self.name)
@@ -99,6 +101,10 @@ class Role(object):
 
     def delete(self):
         response = None
+        if not self.exists():
+            LOG.debug('role %s does not exist - skipping delete', self.name)
+            return response
+
         LOG.debug('deleting role %s', self.name)
         try:
             LOG.debug('First detach the policy from the role')
@@ -117,11 +123,7 @@ class Role(object):
 
     def status(self):
         LOG.debug('getting status for role %s', self.name)
-        try:
-            response = self._iam_client.call(
-                'get_role', RoleName=self.name)
-            LOG.debug(response)
-        except ClientError:
+        role = self._get_role()
+        if not role:
             LOG.debug('role %s not found', self.name)
-            response = None
-        return response
+        return role

@@ -108,8 +108,8 @@ def status(ctx):
     click.echo(click.style('Role', bold=True))
     if status['role']:
         line = '    {} ({})'.format(
-            status['role']['Role']['RoleName'],
-            status['role']['Role']['Arn'])
+            status['role']['RoleName'],
+            status['role']['Arn'])
         click.echo(click.style(line, fg='green'))
     click.echo(click.style('Function', bold=True))
     if status['function']:

+# -*- coding: utf-8 -*-
+# Copyright (c) 2015 Mitch Garnaat http://garnaat.org/
+#
+# Licensed under the Apache License, Version 2.0 (the "License"). You
+# may not use this file except in compliance with the License. A copy of
+# the License is located at
+#
+# http://aws.amazon.com/apache2.0/
+#
+# or in the "license" file accompanying this file. This file 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.
+
+import unittest
+import random
+import string
+from mock import Mock, call
+
+from kappa.role import Role
+
+
+def randomword(length):
+    return ''.join(random.choice(string.printable) for i in range(length))
+
+
+class TestRole(unittest.TestCase):
+
+    def setUp(self):
+        self.iam_client = Mock()
+        policy = type('Policy', (object,), {
+            'arn': None
+        })
+        self.context = type('Context', (object,), {
+            'name': randomword(10),
+            'environment': randomword(10),
+            'policy': policy
+        })
+        self.role_record = {
+            'RoleName': '%s_%s' % (self.context.name,
+                                   self.context.environment),
+            'Arn': randomword(10)
+        }
+        self.role = Role(self.context, None, iam_client=self.iam_client)
+
+    def _expect_get_role(self):
+        get_role_resp = {'Role': self.role_record}
+        self.iam_client.configure_mock(**{
+            'call.return_value': get_role_resp
+        })
+        return get_role_resp
+
+    def test_delete_no_ops_if_role_not_found(self):
+        self.iam_client.configure_mock(**{
+            'call.return_value': None
+        })
+        self.assertEquals(None, self.role.delete())
+        self.assertEquals(1, self.iam_client.call.call_count)
+
+    def test_delete_when_role_exists(self):
+        get_role_resp = self._expect_get_role()
+        self.assertEquals(get_role_resp, self.role.delete())
+        self.iam_client.call.assert_has_calls([call('get_role',
+                                                    RoleName=self.role.name),
+                                               call('delete_role',
+                                                    RoleName=self.role.name)])
+
+    def test_delete_policy_when_context_arn_exists(self):
+        self.context.policy.arn = randomword(10)
+        get_role_resp = self._expect_get_role()
+        self.assertEquals(get_role_resp, self.role.delete())
+        calls = [call('get_role',
+                      RoleName=self.role.name),
+                 call('detach_role_policy',
+                      RoleName=self.role.name,
+                      PolicyArn=self.context.policy.arn),
+                 call('delete_role',
+                      RoleName=self.role.name)]
+        self.iam_client.call.assert_has_calls(calls)