Fails to get metadata versions without X-Instance-Id when using quantum metadata proxy

[Hyunsun Moon]

I'm not sure this is bug or not, but it looks like.
When I tries to get metadata service availability for health check with 'curl http://meta_service_ip:8775' , metadata service returns 400 error with the message that X-Instance-ID is missing. (I enabled quantum metadta proxy)

Looking at the related codes, I can see that the service returns available versions without X-Instance-ID checking if no additional path passed.

nova/api/metadata/handler.py
--------------------
class MetadataRequestHandler(wsgi.Application):

    @webob.dec.wsgify(RequestClass=wsgi.Request)
    def __call__(self, req):
        if os.path.normpath("/" + req.path_info) == "/":
            return(base.ec2_md_print(base.VERSIONS + ["latest"]))
--------------------

But os.path.normpath("/" + req.path_info) returns "//" not "/" if I send request "http://meta_service_ip:8775" or "http://meta_service_ip:8775/".
If I remove "/" from ("/" + req.path_info) it works fine and the service returns version correctly.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/36775

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/36775
Committed: http://github.com/openstack/nova/commit/64bdf2a163bca0505541903229e1072a36bba87f
Submitter: Jenkins
Branch: master

commit 64bdf2a163bca0505541903229e1072a36bba87f
Author: Hyunsun Moon <email address hidden>
Date: Fri Jul 12 12:49:46 2013 +0900

    Fix accessing to '/' of metadata server without any checks to work

    Accessing to '/' of metadata server to get version information should
    be allowed without any checks. Due to the wrong comparison condition,
    it failed.

    Change-Id: Ia8603c321839b959b120af1d018f061f438155c7
    Fixes: bug #1192774