def cached_time_series(identifier, start, end):
"""
Cached time series
"""
def time_series_key(identifier, start, end):
return str(hash(('ts::%s::%s:%s' % (
str(identifier), start, end)).replace(' ', '_')))
cache_key = time_series_key(identifier, start, end)
ts = cache.get(cache_key)
if ts is None:
# Actually fetching time series
source_name = identifier['fews_norm_source_slug']
source = FewsNormSource.objects.get(slug=source_name)
params = {}
if 'geo_ident' in identifier:
params['location'] = identifier['geo_ident']
if 'par_ident' in identifier:
params['parameter'] = identifier['par_ident']
if 'mod_ident' in identifier:
params['moduleinstance'] = identifier['mod_ident']
if 'stp_ident' in identifier:
params['timestep'] = identifier['stp_ident']
if 'qua_ident' in identifier and identifier['qua_ident']:
params['qualifierset'] = identifier['qua_ident']
series = Series.from_raw(
schema_prefix=source.database_schema_name,
params=params).using(source.database_name)
ts = Event.time_series(source, series, start, end)
cache.set(cache_key, ts)
return ts
def series(self):
"""Return Series corresponding with this object"""
params = self.series_params()
source = self.fews_norm_source
series = Series.from_raw(
schema_prefix=source.database_schema_name,
params=params).using(source.database_name)
return series
def get(self, request):
deadline = datetime.strptime(request.GET['timestamp'],
"%Y-%m-%dT%H:%M:%S")
lppairs = [tuple(k.split(':')) for k in request.GET['keys'].split(',')]
filtered_series = Series.from_lppairs(lppairs)
if filtered_series:
e = Event.filter_latest_before_deadline(filtered_series, deadline)
return [(i.series.location.id, i.series.parameter.id, i.timestamp,
i.value, i.flag, i.comment) for i in e]
else:
return None