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  • Committer: Chad Smith
  • Date: 2014-02-11 19:59:05 UTC
  • Revision ID: chad.smith@canonical.com-20140211195905-q7daqsm1mhmg6orh
add _get_persisent_data and _persist_data functions to hooks.py to work around juju-core bug:1279018

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hooks/hooks.py
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from charmhelpers.core import hookenv
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from charmhelpers.core.hookenv import ERROR, INFO
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import json
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import os
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import sys
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hooks = hookenv.Hooks()
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PERSIST_DATA_FILE = "charm-data"
 
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def _persist_data(key, value):
 
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    """Save C{key} and C{value} pairs in a persistent file for reference"""
 
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    data = {}
 
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    filepath = "%s/%s" % (hookenv.charm_dir(), PERSIST_DATA_FILE)
 
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    if os.path.exists(filepath):
 
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        with open(filepath) as inputfile:
 
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            data = json.load(inputfile)
 
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    data[key] = value
 
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    with open(filepath, "w") as outfile:
 
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        outfile.write(unicode(json.dumps(data, ensure_ascii=False)))
 
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def _get_persistent_data(key=None, remove_values=False):
 
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    """Get a persistent data as specified by C{key} from the PERSIST_DATA_FILE
 
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    If C{remove_values} is C{True} remove the specified C{key} from the data
 
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    file.
 
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    """
 
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    data = {}
 
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    filepath = "%s/%s" % (hookenv.charm_dir(), PERSIST_DATA_FILE)
 
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    with open(filepath) as inputfile:
 
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        data = json.load(inputfile)
 
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    if key:
 
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        value = data.get(key, None)
 
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        if remove_values:
 
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            data.pop(key, None)
 
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            if data:
 
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                with open(filepath, "w") as outfile:
 
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                    outfile.write(
 
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                        unicode(json.dumps(data, ensure_ascii=False)))
 
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    else:
 
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        value = data
 
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        if remove_values:
 
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            if os.path.exists(filepath):
 
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                os.remove(filepath)
 
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    return value
 
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@hooks.hook()
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def config_changed():
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def block_storage_relation_departed():
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    """Detach a nova volume from the related instance when relation departs"""
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    import nova_util
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    instance_id = hookenv.relation_get('instance-id')
 
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    # XXX juju bug:1279018 for departed-hooks to see relation-data
 
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    instance_id = _get_persistent_data(
 
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        hookenv.remote_unit(), remove_values=True)
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    if not instance_id:
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        hookenv.log(
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            "Cannot detach nova volume from instance without instance-id",
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    import nova_util
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    instance_id = hookenv.relation_get('instance-id')
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    volume_label = hookenv.relation_get('volume-label')
 
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    _persist_data(hookenv.remote_unit(), instance_id)
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    if not instance_id:
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        hookenv.log("Waiting for relation to define instance-id", INFO)
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        return