Source code for heat.engine.timestamp

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from heat.common import exception

[docs]class Timestamp(object): """A descriptor for writing a timestamp to the database.""" def __init__(self, db_fetch, attribute): """Initialise the timestamp descriptor. Initialise with a function to fetch the database representation of an object (given a context and ID) and the name of the attribute to retrieve. """ self.db_fetch = db_fetch self.attribute = attribute def __get__(self, obj, obj_class): """Get timestamp for the given object and class.""" if obj is None or is None: return None o = self.db_fetch(obj.context, return getattr(o, self.attribute) def __set__(self, obj, timestamp): """Update the timestamp for the given object.""" if is None: raise exception.ResourceNotAvailable( o = self.db_fetch(obj.context, o.update_and_save({self.attribute: timestamp})