Remove unused tasks

Deleted three Celery tasks (send-email, send-sms and persist-letter).

These are not being used anymore - we replaced them in commit
0c9a4bce59.

app/celery/tasks.py

@@ -180,53 +180,6 @@ def __sending_limits_for_job_exceeded(service, job, job_id):
     return False
 
 
-@notify_celery.task(bind=True, name="send-sms", max_retries=5, default_retry_delay=300)
-@statsd(namespace="tasks")
-def send_sms(self,
-             service_id,
-             notification_id,
-             encrypted_notification,
-             created_at,
-             api_key_id=None,
-             key_type=KEY_TYPE_NORMAL):
-    notification = encryption.decrypt(encrypted_notification)
-    service = dao_fetch_service_by_id(service_id)
-
-    if not service_allowed_to_send_to(notification['to'], service, key_type):
-        current_app.logger.info(
-            "SMS {} failed as restricted service".format(notification_id)
-        )
-        return
-
-    try:
-        saved_notification = persist_notification(
-            template_id=notification['template'],
-            template_version=notification['template_version'],
-            recipient=notification['to'],
-            service=service,
-            personalisation=notification.get('personalisation'),
-            notification_type=SMS_TYPE,
-            api_key_id=api_key_id,
-            key_type=key_type,
-            created_at=datetime.utcnow(),
-            job_id=notification.get('job', None),
-            job_row_number=notification.get('row_number', None),
-            notification_id=notification_id
-        )
-
-        provider_tasks.deliver_sms.apply_async(
-            [str(saved_notification.id)],
-            queue=QueueNames.SEND_SMS if not service.research_mode else QueueNames.RESEARCH_MODE
-        )
-
-        current_app.logger.info(
-            "SMS {} created at {} for job {}".format(saved_notification.id, created_at, notification.get('job', None))
-        )
-
-    except SQLAlchemyError as e:
-        handle_exception(self, notification, notification_id, e)
-
-
 @notify_celery.task(bind=True, name="save-sms", max_retries=5, default_retry_delay=300)
 @statsd(namespace="tasks")
 def save_sms(self,
@@ -276,48 +229,6 @@ def save_sms(self,
         handle_exception(self, notification, notification_id, e)
 
 
-@notify_celery.task(bind=True, name="send-email", max_retries=5, default_retry_delay=300)
-@statsd(namespace="tasks")
-def send_email(self,
-               service_id,
-               notification_id,
-               encrypted_notification,
-               created_at,
-               api_key_id=None,
-               key_type=KEY_TYPE_NORMAL):
-    notification = encryption.decrypt(encrypted_notification)
-    service = dao_fetch_service_by_id(service_id)
-
-    if not service_allowed_to_send_to(notification['to'], service, key_type):
-        current_app.logger.info("Email {} failed as restricted service".format(notification_id))
-        return
-
-    try:
-        saved_notification = persist_notification(
-            template_id=notification['template'],
-            template_version=notification['template_version'],
-            recipient=notification['to'],
-            service=service,
-            personalisation=notification.get('personalisation'),
-            notification_type=EMAIL_TYPE,
-            api_key_id=api_key_id,
-            key_type=key_type,
-            created_at=datetime.utcnow(),
-            job_id=notification.get('job', None),
-            job_row_number=notification.get('row_number', None),
-            notification_id=notification_id
-        )
-
-        provider_tasks.deliver_email.apply_async(
-            [str(saved_notification.id)],
-            queue=QueueNames.SEND_EMAIL if not service.research_mode else QueueNames.RESEARCH_MODE
-        )
-
-        current_app.logger.info("Email {} created at {}".format(saved_notification.id, created_at))
-    except SQLAlchemyError as e:
-        handle_exception(self, notification, notification_id, e)
-
-
 @notify_celery.task(bind=True, name="save-email", max_retries=5, default_retry_delay=300)
 @statsd(namespace="tasks")
 def save_email(self,
@@ -359,43 +270,6 @@ def save_email(self,
         handle_exception(self, notification, notification_id, e)
 
 
-@notify_celery.task(bind=True, name="persist-letter", max_retries=5, default_retry_delay=300)
-@statsd(namespace="tasks")
-def persist_letter(
-    self,
-    service_id,
-    notification_id,
-    encrypted_notification,
-    created_at
-):
-    notification = encryption.decrypt(encrypted_notification)
-
-    # we store the recipient as just the first item of the person's address
-    recipient = notification['personalisation']['addressline1']
-
-    service = dao_fetch_service_by_id(service_id)
-    try:
-        saved_notification = persist_notification(
-            template_id=notification['template'],
-            template_version=notification['template_version'],
-            recipient=recipient,
-            service=service,
-            personalisation=notification['personalisation'],
-            notification_type=LETTER_TYPE,
-            api_key_id=None,
-            key_type=KEY_TYPE_NORMAL,
-            created_at=datetime.utcnow(),
-            job_id=notification['job'],
-            job_row_number=notification['row_number'],
-            notification_id=notification_id,
-            reference=create_random_identifier()
-        )
-
-        current_app.logger.info("Letter {} created at {}".format(saved_notification.id, created_at))
-    except SQLAlchemyError as e:
-        handle_exception(self, notification, notification_id, e)
-
-
 @notify_celery.task(bind=True, name="save-letter", max_retries=5, default_retry_delay=300)
 @statsd(namespace="tasks")
 def save_letter(