Fix misused assertTrue in unit tests

Refactored unit tests to use assertEqual instead of assertTrue
where needed.

Fixes bug #1226374

Change-Id: I6ee1e3671054c4604ebb38ca9ceb52e8aef28540
diff --git a/tempest/api/compute/images/test_image_metadata.py b/tempest/api/compute/images/test_image_metadata.py
index a769744..0a6ac80 100644
--- a/tempest/api/compute/images/test_image_metadata.py
+++ b/tempest/api/compute/images/test_image_metadata.py
@@ -89,7 +89,7 @@
         # The value for a specific metadata key should be returned
         resp, meta = self.client.get_image_metadata_item(self.image_id,
                                                          'key2')
-        self.assertTrue('value2', meta['key2'])
+        self.assertEqual('value2', meta['key2'])
 
     @attr(type='gate')
     def test_set_image_metadata_item(self):
diff --git a/tempest/api/compute/servers/test_multiple_create.py b/tempest/api/compute/servers/test_multiple_create.py
index edfafec..7e4a70b 100644
--- a/tempest/api/compute/servers/test_multiple_create.py
+++ b/tempest/api/compute/servers/test_multiple_create.py
@@ -87,7 +87,7 @@
                                                    min_count=1,
                                                    max_count=2,
                                                    return_reservation_id=True)
-        self.assertTrue(resp['status'], 202)
+        self.assertEqual(resp['status'], '202')
         self.assertIn('reservation_id', body)
 
 
diff --git a/tempest/api/compute/servers/test_server_metadata.py b/tempest/api/compute/servers/test_server_metadata.py
index 9997b97..d396129 100644
--- a/tempest/api/compute/servers/test_server_metadata.py
+++ b/tempest/api/compute/servers/test_server_metadata.py
@@ -118,7 +118,7 @@
         # The value for a specific metadata key should be returned
         resp, meta = self.client.get_server_metadata_item(self.server_id,
                                                           'key2')
-        self.assertTrue('value2', meta['key2'])
+        self.assertEqual('value2', meta['key2'])
 
     @attr(type='gate')
     def test_set_server_metadata_item(self):
diff --git a/tempest/api/volume/admin/test_volume_types.py b/tempest/api/volume/admin/test_volume_types.py
index b15f8dd..66b6969 100644
--- a/tempest/api/volume/admin/test_volume_types.py
+++ b/tempest/api/volume/admin/test_volume_types.py
@@ -52,7 +52,7 @@
         # List Volume types.
         resp, body = self.client.list_volume_types()
         self.assertEqual(200, resp.status)
-        self.assertTrue(type(body), list)
+        self.assertIsInstance(body, list)
 
     @attr(type='smoke')
     def test_create_get_delete_volume_with_volume_type_and_extra_specs(self):
diff --git a/tempest/api/volume/admin/test_volume_types_extra_specs.py b/tempest/api/volume/admin/test_volume_types_extra_specs.py
index 7d94f58..12ecaac 100644
--- a/tempest/api/volume/admin/test_volume_types_extra_specs.py
+++ b/tempest/api/volume/admin/test_volume_types_extra_specs.py
@@ -46,7 +46,7 @@
         resp, body = self.client.list_volume_types_extra_specs(
             self.volume_type['id'])
         self.assertEqual(200, resp.status)
-        self.assertTrue(type(body), dict)
+        self.assertIsInstance(body, dict)
         self.assertTrue('spec1' in body, "Incorrect volume type extra"
                         " spec returned")