"--resource-metadata" is unavailable in sample-create

[Liusheng]

When I use following commands try to create a sample with resource medatada:

ceilometer --debug sample-create -r resource1 -m meter1 --meter-type delta --meter-unit unit1 --sample-volume 1 --resource-metadata abc=abc

CLI will raise an ValueError with the traceback:
Traceback (most recent call last):
  File "/usr/local/bin/ceilometer", line 10, in <module>
    sys.exit(main())
  File "/opt/stack/python-ceilometerclient/ceilometerclient/shell.py", line 335, in main
    CeilometerShell().main(args)
  File "/opt/stack/python-ceilometerclient/ceilometerclient/shell.py", line 289, in main
    args.func(client, args)
  File "/opt/stack/python-ceilometerclient/ceilometerclient/v2/shell.py", line 161, in do_sample_create
    fields[k] = json.loads(v)
  File "/usr/lib/python2.7/json/__init__.py", line 326, in loads
    return _default_decoder.decode(s)
  File "/usr/lib/python2.7/json/decoder.py", line 366, in decode
    obj, end = self.raw_decode(s, idx=_w(s, 0).end())
  File "/usr/lib/python2.7/json/decoder.py", line 384, in raw_decode
    raise ValueError("No JSON object could be decoded")
ValueError: No JSON object could be decoded

[ZhiQiang Fan (aji-zqfan)]

oops, there is no test code for this scenarios

[Liusheng (liusheng)]

@ZhiQiang, the right way to use the resource-metadata in sample-create is:

ceilometer --debug sample-create -r resource1 -m meter1 --meter-type delta --meter-unit unit1 --sample-volume 1 --resource-metadata '{"abc":"abc"}'

but unlike other metadata commands in openstack, is the usage a little weird?

[ZhiQiang Fan (aji-zqfan)]

at least, the error message is not quite useful for end users, we need a good example in help string, or in test code (I always try to find example use case in test code)

[Liusheng (liusheng)]

agree, the error message and the help string unreasonable or change the usage of --resource-metadata to allowing user specifying key value pairs in CLI like nova or cinder CLI :)

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/97674

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/97674
Committed: https://git.openstack.org/cgit/openstack/python-ceilometerclient/commit/?id=67183f76b692d74fb255151e682ad7ce0171a01e
Submitter: Jenkins
Branch: master

commit 67183f76b692d74fb255151e682ad7ce0171a01e
Author: liu-sheng <email address hidden>
Date: Wed Jun 4 10:46:44 2014 +0800

    Provide explicit help string of resource-metadata

    Currently, the "--resource-metadata" in ceilometer sample-create command
    is not easy to use. For compatibility, this patch just provides an
    explicit help string for the parameter.

    Change-Id: I6d68d5b653c3b33808cba6f9a781301fba9b44e3
    Closes-Bug: #1324759