For euca-describe-instances invalid instance id is not getting validated

Fix proposed to branch: master
Review: https://review.openstack.org/12937

New output format:

euca-describe-instances i-00000045 i-00000012
RESERVATION r-16epayoe 4b8378b8f1a245e2aa1f3b77761bfe5e default
INSTANCE i-00000012 ami-00000001 172.24.4.227 novdemob0ii0--onhost--nv-aw1st running testkey 0 m1.tiny 2012-09-21T17:40:48.000Z nova aki-00000002 ari-00000003 monitoring-disabled 172.24.4.227 10.0.0.10 instance-store
RESERVATION Instance i-00000045 does not exist
INSTANCE i-00000045 does not exist monitoring-disabled
INSTANCE i-00000045 does not exist monitoring-disabled

Also changed the euca.sh script in devstack repository to support the new change
please find the change at https://review.openstack.org/#/c/13460/

Is this implemented in any of the other ec2 apis (eucalyptus, ec2)? I don't think it makes sense to come up with our own syntax for this.

 Hi Vish,not sure if this answer your question from one of the bug from eucalyptus(https://eucalyptus.atlassian.net/browse/EUCA-2346) I found this

 There are two different responses from AWS depending on the type of error:

1) If you specify an instance ID that could not ever be valid (as in Patrick's example of 'zzzzzzzz'), you get this code: InvalidInstanceID.Malformed

2) If you specify an instance ID that could be valid (i.e., conforms to the specification of an instance ID), you also get a 400 HTTP status, but you get this response:

<Response><Errors><Error><Code>InvalidInstanceID.NotFound</Code><Message>The instance ID 'i-abcdabcd' does not exist</Message></Error></Errors><RequestID>29aec988-c656-49f0-9a26-242a19c1b4d1</RequestID></Response>

In both cases, Eucalyptus simply returns an empty set.
The above link talks about the scenario when user tries to get details for one instance

but as per Openstack euca-describe-instances accepts multiple values as input and if user req euca-describe-instances with
both valid and invalid id's then the details of the only valid instances are being displayed and <invalid or non-exsiting> id's are ignored silently.
How can an end user can be notified in the above case?

I think that someone should try running a multiple describe against ec2 with one valid id. We should emulate that behavior