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Viewing changes to charmworld/lib/deployer.py

  • Committer: Rick Harding
  • Date: 2013-10-31 17:27:29 UTC
  • mfrom: (435 trunk)
  • mto: (436.1.2 api-doc-updates)
  • mto: This revision was merged to the branch mainline in revision 437.
  • Revision ID: rick.harding@canonical.com-20131031172729-u7cxl8ox3awl2o55
Update deployer version and it's deps, make that work

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charmworld/lib/deployer.py
 
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"""Helpers for dealing with deployer files."""
 
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from copy import deepcopy
 
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import yaml
 
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from charmworld.lib.proof import ProofError
 
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def parse_deployer(data, format='yaml'):
 
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    try:
 
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        return yaml.safe_load(data)
 
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    except yaml.YAMLError, exc:
 
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        raise ProofError(
 
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            [
 
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                data,
 
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                str(exc)
 
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            ],
 
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            'Could not parse the yaml provided.'
 
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        )
 
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class CycleDetected(Exception):
 
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    """An inheritance cycle was detected in a deployment config."""
 
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    def __init__(self, key):
 
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        super(CycleDetected, self).__init__(
 
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            'An inheritance cycle was detected involving deployment "%s"'
 
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            % key)
 
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# Utils from deployer 1
 
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def relations_combine(onto, source):
 
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    target = deepcopy(onto)
 
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    # Support list of relations targets
 
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    if isinstance(onto, list) and isinstance(source, list):
 
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        target.extend(source)
 
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        return target
 
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    for (key, value) in source.items():
 
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        if key in target:
 
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            if isinstance(target[key], dict) and isinstance(value, dict):
 
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                target[key] = relations_combine(target[key], value)
 
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            elif isinstance(target[key], list) and isinstance(value, list):
 
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                target[key] = list(set(target[key] + value))
 
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        else:
 
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            target[key] = value
 
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    return target
 
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def dict_merge(onto, source):
 
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    target = deepcopy(onto)
 
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    for (key, value) in source.items():
 
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        if key == 'relations' and key in target:
 
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            target[key] = relations_combine(target[key], value)
 
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        elif (key in target and isinstance(target[key], dict) and
 
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                isinstance(value, dict)):
 
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            target[key] = dict_merge(target[key], value)
 
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        else:
 
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            target[key] = value
 
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    return target
 
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def inherits(d):
 
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    parents = d.get('inherits', ())
 
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    if isinstance(parents, basestring):
 
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        parents = [parents]
 
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    return parents
 
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def get_flattened_deployment(data, key, seen=None):
 
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    """This flattens the inheritance hierarchy.
 
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    This is provided as a public API for tools, such as Charmworld, that need
 
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    to parse deployment configs.
 
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    """
 
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    if seen is None:
 
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        seen = set()
 
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    elif key in seen:
 
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        raise CycleDetected(key)
 
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    deploy_data = data[key]
 
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    if not 'inherits' in deploy_data:
 
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        return deploy_data
 
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    parents = inherits(deploy_data)
 
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    for parent_name in parents:
 
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        parent_data = get_flattened_deployment(
 
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            data, parent_name, seen | set([key]))
 
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        parents.extend(inherits(parent_data))
 
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        deploy_data = dict_merge(deploy_data, parent_data)
 
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    deploy_data['inherits'] = parents
 
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    return deploy_data