def collect_predictions():
"""Retrieve predictions for the routes that are monitored
Be aware of NextBus API rate limits:
- 2MB/20sec,
- 150 stops per prediction
"""
nb = NextBus()
monitored_routes = Route.objects.filter(monitored=True)
for route in monitored_routes:
all_stops = route.stops.all()
p = Paginator(all_stops, 150) # Paginate routes with more than 150 stops
for page_number in p.page_range:
page = p.page(page_number)
stops = page.object_list
stop_tags = ['%s|%s' % (stop.route.tag, stop.tag) for stop in stops]
predictions = nb.get_first_prediction_multi_stops(settings.AGENCY_TAG, stop_tags)
for prediction in predictions:
new_prediction = Prediction(
seconds=prediction[1],
stop=Stop.objects.filter(tag=prediction[0]).first()
)
new_prediction.save()
def test_get_first_prediction_multi_stops(self):
with HTTMock(nextbus_multistops_predictions_mock):
nb = NextBus()
predictions = nb.get_first_prediction_multi_stops("ttc", ["512|14295", "512|14688"])
self.assertEqual(int(predictions[0][1]), 502) # first prediction for first stop in fake dataset
