Completely remove code to switch sms providers on slow delivery

app/celery/scheduled_tasks.py

@@ -32,13 +32,11 @@ from app.dao.jobs_dao import (
 from app.dao.notifications_dao import (
     dao_old_letters_with_created_status,
     dao_precompiled_letters_still_pending_virus_check,
-    is_delivery_slow_for_providers,
     letters_missing_from_sending_bucket,
     notifications_not_yet_sent,
 )
 from app.dao.provider_details_dao import (
     dao_adjust_provider_priority_back_to_resting_points,
-    dao_reduce_sms_provider_priority,
 )
 from app.dao.services_dao import (
     dao_find_services_sending_to_tv_numbers,
@@ -95,28 +93,6 @@ def delete_invitations():
         raise
 
 
-@notify_celery.task(name='switch-current-sms-provider-on-slow-delivery')
-def switch_current_sms_provider_on_slow_delivery():
-    """
-    Reduce provider's priority if at least 30% of notifications took more than four minutes to be delivered
-    in the last ten minutes. If both providers are slow, don't do anything. If we changed the providers in the
-    last ten minutes, then don't update them again either.
-    """
-    slow_delivery_notifications = is_delivery_slow_for_providers(
-        threshold=0.3,
-        created_at=datetime.utcnow() - timedelta(minutes=10),
-        delivery_time=timedelta(minutes=4),
-    )
-
-    # only adjust if some values are true and some are false - ie, don't adjust if all providers are fast or
-    # all providers are slow
-    if len(set(slow_delivery_notifications.values())) != 1:
-        for provider_name, is_slow in slow_delivery_notifications.items():
-            if is_slow:
-                current_app.logger.warning('Slow delivery notifications detected for provider {}'.format(provider_name))
-                dao_reduce_sms_provider_priority(provider_name, time_threshold=timedelta(minutes=10))
-
-
 @notify_celery.task(name='tend-providers-back-to-middle')
 def tend_providers_back_to_middle():
     dao_adjust_provider_priority_back_to_resting_points()

app/config.py

@@ -215,11 +215,6 @@ class Config(object):
                 'schedule': timedelta(minutes=66),
                 'options': {'queue': QueueNames.PERIODIC}
             },
-            # 'switch-current-sms-provider-on-slow-delivery': {
-            #     'task': 'switch-current-sms-provider-on-slow-delivery',
-            #     'schedule': crontab(),  # Every minute
-            #     'options': {'queue': QueueNames.PERIODIC}
-            # },
             'check-job-status': {
                 'task': 'check-job-status',
                 'schedule': crontab(),

tests/app/celery/test_scheduled_tasks.py

@@ -20,11 +20,9 @@ from app.celery.scheduled_tasks import (
     delete_verify_codes,
     replay_created_notifications,
     run_scheduled_jobs,
-    switch_current_sms_provider_on_slow_delivery,
 )
 from app.config import QueueNames, TaskNames, Test
 from app.dao.jobs_dao import dao_get_job_by_id
-from app.dao.provider_details_dao import get_provider_details_by_identifier
 from app.models import (
     JOB_STATUS_ERROR,
     JOB_STATUS_FINISHED,
@@ -37,19 +35,6 @@ from tests.app import load_example_csv
 from tests.app.db import create_job, create_notification, create_template
 
 
-def _create_slow_delivery_notification(template, provider='mmg'):
-    now = datetime.utcnow()
-    five_minutes_from_now = now + timedelta(minutes=5)
-
-    create_notification(
-        template=template,
-        status='delivered',
-        sent_by=provider,
-        updated_at=five_minutes_from_now,
-        sent_at=now,
-    )
-
-
 def test_should_call_delete_codes_on_delete_verify_codes_task(notify_db_session, mocker):
     mocker.patch('app.celery.scheduled_tasks.delete_codes_older_created_more_than_a_day_ago')
     delete_verify_codes()
@@ -98,47 +83,6 @@ def test_should_update_all_scheduled_jobs_and_put_on_queue(sample_template, mock
     ])
 
 
-@freeze_time('2017-05-01 14:00:00')
-def test_switch_current_sms_provider_on_slow_delivery_switches_when_one_provider_is_slow(
-    mocker,
-    restore_provider_details,
-):
-    is_slow_dict = {'mmg': False, 'firetext': True}
-    mock_is_slow = mocker.patch('app.celery.scheduled_tasks.is_delivery_slow_for_providers', return_value=is_slow_dict)
-    mock_reduce = mocker.patch('app.celery.scheduled_tasks.dao_reduce_sms_provider_priority')
-    # updated_at times are older than the 10 minute window
-    get_provider_details_by_identifier('mmg').updated_at = datetime(2017, 5, 1, 13, 49)
-    get_provider_details_by_identifier('firetext').updated_at = None
-
-    switch_current_sms_provider_on_slow_delivery()
-
-    mock_is_slow.assert_called_once_with(
-        threshold=0.3,
-        created_at=datetime(2017, 5, 1, 13, 50),
-        delivery_time=timedelta(minutes=4)
-    )
-    mock_reduce.assert_called_once_with('firetext', time_threshold=timedelta(minutes=10))
-
-
-@freeze_time('2017-05-01 14:00:00')
-@pytest.mark.parametrize('is_slow_dict', [
-    {'mmg': False, 'firetext': False},
-    {'mmg': True, 'firetext': True},
-])
-def test_switch_current_sms_provider_on_slow_delivery_does_nothing_if_no_need(
-    mocker,
-    restore_provider_details,
-    is_slow_dict
-):
-    mocker.patch('app.celery.scheduled_tasks.is_delivery_slow_for_providers', return_value=is_slow_dict)
-    mock_reduce = mocker.patch('app.celery.scheduled_tasks.dao_reduce_sms_provider_priority')
-    get_provider_details_by_identifier('mmg').updated_at = datetime(2017, 5, 1, 13, 51)
-
-    switch_current_sms_provider_on_slow_delivery()
-
-    assert mock_reduce.called is False
-
-
 def test_check_job_status_task_calls_process_incomplete_jobs(mocker, sample_template):
     mock_celery = mocker.patch('app.celery.tasks.process_incomplete_jobs.apply_async')
     job = create_job(template=sample_template, notification_count=3,