Empty JSON caused: Error during ComputeManager._run_image_cache_manager_pass: No JSON object could be decoded

[Alvaro Lopez]

Hi.

An empty file CONF.instances_path/compute_nodes is causing the following
error. This prevents the image cache manager to run (i do not know if it has
some other consequences):

    INFO nova.compute.resource_tracker [-] Compute_service record updated for XXX.ifca.es:XXX.ifca.es
    ERROR nova.openstack.common.periodic_task [-] Error during ComputeManager._run_image_cache_manager_pass: No JSON object could be decoded
    TRACE nova.openstack.common.periodic_task Traceback (most recent call last):
    TRACE nova.openstack.common.periodic_task File "/usr/lib/python2.7/dist-packages/nova/openstack/common/periodic_task.py", line 180, in run_periodic_tasks
    TRACE nova.openstack.common.periodic_task task(self, context)
    TRACE nova.openstack.common.periodic_task File "/usr/lib/python2.7/dist-packages/nova/compute/manager.py", line 5040, in _run_image_cache_manager_pass
    TRACE nova.openstack.common.periodic_task storage_users.register_storage_use(CONF.instances_path, CONF.host)
    TRACE nova.openstack.common.periodic_task File "/usr/lib/python2.7/dist-packages/nova/virt/storage_users.py", line 65, in register_storage_use
    TRACE nova.openstack.common.periodic_task return do_register_storage_use(storage_path, hostname)
    TRACE nova.openstack.common.periodic_task File "/usr/lib/python2.7/dist-packages/nova/openstack/common/lockutils.py", line 246, in inner
    TRACE nova.openstack.common.periodic_task return f(*args, **kwargs)
    TRACE nova.openstack.common.periodic_task File "/usr/lib/python2.7/dist-packages/nova/virt/storage_users.py", line 58, in do_register_storage_use
    TRACE nova.openstack.common.periodic_task d = json.loads(f.read())
    TRACE nova.openstack.common.periodic_task File "/usr/lib/python2.7/json/__init__.py", line 328, in loads
    TRACE nova.openstack.common.periodic_task return _default_decoder.decode(s)
    TRACE nova.openstack.common.periodic_task File "/usr/lib/python2.7/json/decoder.py", line 365, in decode
    TRACE nova.openstack.common.periodic_task obj, end = self.raw_decode(s, idx=_w(s, 0).end())
    TRACE nova.openstack.common.periodic_task File "/usr/lib/python2.7/json/decoder.py", line 383, in raw_decode
    TRACE nova.openstack.common.periodic_task raise ValueError("No JSON object could be decoded")
    TRACE nova.openstack.common.periodic_task ValueError: No JSON object could be decoded
    TRACE nova.openstack.common.periodic_task

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/57143

[George Shuklin (george-shuklin)]

I've checked patchset #9, it works perferctly on ubuntu-cloud-archive version of nova.

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/57143
Committed: https://git.openstack.org/cgit/openstack/nova/commit/?id=80b08a47440e2e0041eb394db4101f29d8e05749
Submitter: Jenkins
Branch: master

commit 80b08a47440e2e0041eb394db4101f29d8e05749
Author: Alvaro Lopez Garcia <email address hidden>
Date: Tue Nov 19 10:10:41 2013 +0100

    Capture exception for JSON load in virt.storage_users

    If CONF.instances_path/compute_nodes is empty when the storage_users
    tries to register the storage use (virt.storage_users.register_storage_use)
    the exception is uncaught and raised. As a consequence, the image cache
    manager won't run.

    Closes-Bug: #1252659

    Change-Id: If9ed5e75b0bc0b8f3a7c5fd7ec88f6399e4e59c6

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: stable/havana
Review: https://review.openstack.org/73792