message: Add basic Impala engine spec
  From:
diff: @@ -978,6 +978,31 @@ class BQEngineSpec(BaseEngineSpec):
  return "'{}'".format(dttm.strftime('%Y-%m-%d %H:%M:%S'))
  +class ImpalaEngineSpec(BaseEngineSpec):
  + """Engine spec for Cloudera's Impala"""
  +
  + engine = 'impala'
  +
  + time_grains = (
  + Grain("Time Column", _('Time Column'), "{col}"),
  + Grain("minute", _('minute'), "TRUNC({col}, 'MI')"),
  + Grain("hour", _('hour'), "TRUNC({col}, 'HH')"),
  + Grain("day", _('day'), "TRUNC({col}, 'DD')"),
  + Grain("week", _('week'), "TRUNC({col}, 'WW')"),
  + Grain("month", _('month'), "TRUNC({col}, 'MONTH')"),
  + Grain("quarter", _('quarter'), "TRUNC({col}, 'Q')"),
  + Grain("year", _('year'), "TRUNC({col}, 'YYYY')"),
  + )
  +
  + @classmethod
  + def convert_dttm(cls, target_type, dttm):
  + tt = target_type.upper()
  + if tt == 'DATE':
  + return "'{}'".format(dttm.strftime('%Y-%m-%d'))
  + else:
  + return "'{}'".format(dttm.strftime('%Y-%m-%d %H:%M:%S'))
  +
  +
  engines = {
  o.engine: o for o in globals().values()
  if inspect.isclass(o) and issubclass(o, BaseEngineSpec)}
  