Attempting to get/delete image member that does not exist returns 404 response with incorrect message

[Luke Wollney]

Overview:
When attempting to get/delete image member that does not exist, a 404 response is returned, but with an incorrect message.

Steps to reproduce:
1) Create an image
2) Try to get or delete image member, passing 'dne' as member id via:
DELETE /images/<image_id>/members/dne
3) Notice that a 404 response is returned and that the message reads 'Image <image_id> not found'

Expected:
A 404 response containing a message that reads 'Image member not found'

Actual:
A 404 response with a message that reads 'Image <image_id> not found'

[Deepti Ramakrishna (dramakri)]

This bug is applicable only for v2 api. For v1 api, we get a "405 Method Not Allowed" response, for which there is a separate bug #1326955 (which is marked as "Won't Fix" BTW).

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/178997

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/178997
Committed: https://git.openstack.org/cgit/openstack/glance/commit/?id=020b21d7164f1995b4a6c36f5aafcaac6e675445
Submitter: Jenkins
Branch: master

commit 020b21d7164f1995b4a6c36f5aafcaac6e675445
Author: Deepti Ramakrishna <email address hidden>
Date: Sun Jun 28 22:48:29 2015 -0700

    Refactoring of image-members v2 API implementation.

    The refactoring is motivated by multiple issues in the current code:
    - Exceptions thrown by image lookup as well as member lookup are handled in
      the same try-except block and handled as if it was only the image lookup
      that failed.
    - Does not take into account that in v2, trying to do any operation on a
      public image members should throw 403 Forbidden error. As a result, the
      current response messages for operations on a public image show an
      "Unauthorized" error message even for admin rather than the more accurate
      "Public images do not have any members" error message.

    Change-Id: Icf73841fbd10204db689b2b28451434ebaf10087
    Closes-Bug: #1444129