Add exception for no default share type configured

There is a particular scenario when creating a new Manila share,
whether through creating a new share or managing an existing one, where
if no share type was explicitly specified and no default share type was
configured the error message would not substitute the share type ID into
the exception message. This is because, in this case, there was no share
type ID to substitute into the string.

This patch creates a new exception for explicitly handling the case
where there is no default share type and no share type is explicitly
given. It gives an appropriate error message about there not being a
default share type and that there was no share type explicitly given as
well as what would need to be done to remedy the situation.

Change-Id: I068b55d4b77dc24b53fe93d870bb84e1aef661a5
Closes-Bug: #1700346

manila/db/sqlalchemy/api.py

@@ -3761,6 +3761,10 @@ def _share_type_get(context, id, session=None, inactive=False,
               first())
 
     if not result:
+        # The only way that id could be None is if the default share type is
+        # not configured and no other share type was specified.
+        if id is None:
+            raise exception.DefaultShareTypeNotConfigured()
         raise exception.ShareTypeNotFound(share_type_id=id)
 
     share_type = _dict_with_specs(result)

manila/exception.py

@@ -649,6 +649,11 @@ class ShareTypeDoesNotExist(NotFound):
     message = _("Share Type %(share_type)s does not exist.")
 
 
+class DefaultShareTypeNotConfigured(NotFound):
+    message = _("No default share type is configured. Either configure a "
+                "default share type or explicitly specify a share type.")
+
+
 class ShareGroupTypeExists(ManilaException):
     message = _("Share group type %(type_id)s already exists.")
 

manila/tests/db/sqlalchemy/test_api.py

@@ -2752,6 +2752,10 @@ class ShareTypeAPITestCase(test.TestCase):
 
         self.assertIsNone(result)
 
+    def test_share_type_get_with_none_id(self):
+        self.assertRaises(exception.DefaultShareTypeNotConfigured,
+                          db_api.share_type_get, self.ctxt, None)
+
 
 class MessagesDatabaseAPITestCase(test.TestCase):
 

manila/tests/test_exception.py

@@ -486,6 +486,11 @@ class ManilaExceptionResponseCode404(test.TestCase):
         self.assertIn(share_type_id, e.msg)
         self.assertIn(extra_specs_key, e.msg)
 
+    def test_default_share_type_not_configured(self):
+        # Verify response code for exception.DefaultShareTypeNotConfigured
+        e = exception.DefaultShareTypeNotConfigured()
+        self.assertEqual(404, e.code)
+
     def test_instance_not_found(self):
         # verify response code for exception.InstanceNotFound
         instance_id = "fake_instance_id"

releasenotes/notes/bug-1700346-new-exception-for-no-default-share-type-b1dd9bbe8c9cb3df.yaml

@@ -0,0 +1,5 @@
+---
+fixes:
+  - A new exception will be thrown when a default share type was not
+    configured and no other share type was specified on any sort of
+    share creation.