Add endpoint for cancelling letters

app/letters/utils.py

@@ -162,3 +162,16 @@ def _move_s3_object(source_bucket, source_filename, target_bucket, target_filena
 
     current_app.logger.info("Moved letter PDF: {}/{} to {}/{}".format(
         source_bucket, source_filename, target_bucket, target_filename))
+
+
+def letter_print_day(created_at):
+    bst_print_datetime = convert_utc_to_bst(created_at) + timedelta(hours=6, minutes=30)
+    bst_print_date = bst_print_datetime.date()
+
+    current_bst_date = convert_utc_to_bst(datetime.utcnow()).date()
+
+    if bst_print_date >= current_bst_date:
+        return 'today'
+    else:
+        print_date = bst_print_datetime.strftime('%d %B').lstrip('0')
+        return 'on {}'.format(print_date)

app/service/rest.py

@@ -7,6 +7,8 @@ from flask import (
     current_app,
     Blueprint
 )
+from notifications_utils.letter_timings import letter_can_be_cancelled
+from notifications_utils.timezones import convert_utc_to_bst
 from sqlalchemy.exc import IntegrityError
 from sqlalchemy.orm.exc import NoResultFound
 
@@ -80,7 +82,8 @@ from app.errors import (
     InvalidRequest,
     register_errors
 )
-from app.models import Service, EmailBranding
+from app.letters.utils import letter_print_day
+from app.models import LETTER_TYPE, NOTIFICATION_CANCELLED, Service, EmailBranding
 from app.schema_validation import validate
 from app.service import statistics
 from app.service.service_data_retention_schema import (
@@ -103,7 +106,7 @@ from app.schemas import (
     notifications_filter_schema,
     detailed_service_schema
 )
-from app.utils import pagination_links, convert_utc_to_bst
+from app.utils import pagination_links
 
 service_blueprint = Blueprint('service', __name__)
 
@@ -384,6 +387,31 @@ def get_notification_for_service(service_id, notification_id):
     ), 200
 
 
+@service_blueprint.route('/<uuid:service_id>/notifications/<uuid:notification_id>/cancel', methods=['POST'])
+def cancel_notification_for_service(service_id, notification_id):
+    notification = notifications_dao.get_notification_by_id(notification_id, service_id)
+
+    if not notification:
+        raise InvalidRequest('Notification not found', status_code=404)
+    elif notification.notification_type != LETTER_TYPE:
+        raise InvalidRequest('Notification cannot be cancelled - only letters can be cancelled', status_code=400)
+    elif not letter_can_be_cancelled(notification.status, notification.created_at):
+        print_day = letter_print_day(notification.created_at)
+
+        raise InvalidRequest(
+            "It’s too late to cancel this letter. Printing started {} at 5.30pm".format(print_day),
+            status_code=400)
+
+    updated_notification = notifications_dao.update_notification_status_by_id(
+        notification_id,
+        NOTIFICATION_CANCELLED,
+    )
+
+    return jsonify(
+        notification_with_template_schema.dump(updated_notification).data
+    ), 200
+
+
 def search_for_notification_by_to_field(service_id, search_term, statuses, notification_type):
     results = notifications_dao.dao_get_notifications_by_to_field(
         service_id=service_id,

tests/app/letters/test_letter_utils.py

@@ -10,6 +10,7 @@ from app.letters.utils import (
     get_bucket_name_and_prefix_for_notification,
     get_letter_pdf_filename,
     get_letter_pdf,
+    letter_print_day,
     upload_letter_pdf,
     ScanErrorType, move_failed_pdf, get_folder_name
 )
@@ -274,3 +275,27 @@ def test_get_folder_name_in_british_summer_time(notify_api, freeze_date, expecte
 
 def test_get_folder_name_returns_empty_string_for_test_letter():
     assert '' == get_folder_name(datetime.utcnow(), is_test_or_scan_letter=True)
+
+
+@freeze_time('2017-07-07 20:00:00')
+def test_letter_print_day_returns_today_if_letter_was_printed_after_1730_yesterday():
+    created_at = datetime(2017, 7, 6, 17, 30)
+    assert letter_print_day(created_at) == 'today'
+
+
+@freeze_time('2017-07-07 16:30:00')
+def test_letter_print_day_returns_today_if_letter_was_printed_today():
+    created_at = datetime(2017, 7, 7, 12, 0)
+    assert letter_print_day(created_at) == 'today'
+
+
+@pytest.mark.parametrize('created_at, formatted_date', [
+    (datetime(2017, 7, 5, 16, 30), 'on 6 July'),
+    (datetime(2017, 7, 6, 16, 29), 'on 6 July'),
+    (datetime(2016, 8, 8, 10, 00), 'on 8 August'),
+    (datetime(2016, 12, 12, 17, 29), 'on 12 December'),
+    (datetime(2016, 12, 12, 17, 30), 'on 13 December'),
+])
+@freeze_time('2017-07-07 16:30:00')
+def test_letter_print_day_returns_formatted_date_if_letter_printed_before_1730_yesterday(created_at, formatted_date):
+    assert letter_print_day(created_at) == formatted_date

tests/app/service/test_rest.py

@@ -2790,3 +2790,114 @@ def test_get_organisation_for_service_id_return_empty_dict_if_service_not_in_org
         service_id=fake_uuid
     )
     assert response == {}
+
+
+def test_cancel_notification_for_service_raises_invalid_request_when_notification_is_not_found(
+    admin_request,
+    sample_service,
+    fake_uuid,
+):
+    response = admin_request.post(
+        'service.cancel_notification_for_service',
+        service_id=sample_service.id,
+        notification_id=fake_uuid,
+        _expected_status=404
+    )
+    assert response['message'] == 'Notification not found'
+    assert response['result'] == 'error'
+
+
+def test_cancel_notification_for_service_raises_invalid_request_when_notification_is_not_a_letter(
+    admin_request,
+    sample_notification,
+):
+    response = admin_request.post(
+        'service.cancel_notification_for_service',
+        service_id=sample_notification.service_id,
+        notification_id=sample_notification.id,
+        _expected_status=400
+    )
+    assert response['message'] == 'Notification cannot be cancelled - only letters can be cancelled'
+    assert response['result'] == 'error'
+
+
+@pytest.mark.parametrize('notification_status', [
+    'cancelled',
+    'sending',
+    'sent',
+    'delivered',
+    'pending',
+    'failed',
+    'technical-failure',
+    'temporary-failure',
+    'permanent-failure',
+    'validation-failed',
+    'virus-scan-failed',
+    'returned-letter',
+])
+@freeze_time('2018-07-07 12:00:00')
+def test_cancel_notification_for_service_raises_invalid_request_when_letter_is_in_wrong_state_to_be_cancelled(
+    admin_request,
+    sample_letter_notification,
+    notification_status,
+):
+    sample_letter_notification.status = notification_status
+
+    response = admin_request.post(
+        'service.cancel_notification_for_service',
+        service_id=sample_letter_notification.service_id,
+        notification_id=sample_letter_notification.id,
+        _expected_status=400
+    )
+    assert response['message'] == 'It’s too late to cancel this letter. Printing started today at 5.30pm'
+    assert response['result'] == 'error'
+
+
+@pytest.mark.parametrize('notification_status', ['created', 'pending-virus-check'])
+@freeze_time('2018-07-07 16:00:00')
+def test_cancel_notification_for_service_updates_letter_if_letter_is_in_cancellable_state(
+    admin_request,
+    sample_letter_notification,
+    notification_status,
+):
+    sample_letter_notification.status = notification_status
+    sample_letter_notification.created_at = datetime.now()
+
+    response = admin_request.post(
+        'service.cancel_notification_for_service',
+        service_id=sample_letter_notification.service_id,
+        notification_id=sample_letter_notification.id,
+    )
+    assert response['status'] == 'cancelled'
+
+
+@freeze_time('2017-12-12 17:30:00')
+def test_cancel_notification_for_service_raises_error_if_its_too_late_to_cancel(
+    admin_request,
+    sample_letter_notification,
+):
+    sample_letter_notification.created_at = datetime(2017, 12, 11, 17, 0)
+
+    response = admin_request.post(
+        'service.cancel_notification_for_service',
+        service_id=sample_letter_notification.service_id,
+        notification_id=sample_letter_notification.id,
+        _expected_status=400
+    )
+    assert response['message'] == 'It’s too late to cancel this letter. Printing started on 11 December at 5.30pm'
+    assert response['result'] == 'error'
+
+
+@freeze_time('2018-7-7 16:00:00')
+def test_cancel_notification_for_service_updates_letter_if_still_time_to_cancel(
+    admin_request,
+    sample_letter_notification,
+):
+    sample_letter_notification.created_at = datetime(2018, 7, 7, 10, 0)
+
+    response = admin_request.post(
+        'service.cancel_notification_for_service',
+        service_id=sample_letter_notification.service_id,
+        notification_id=sample_letter_notification.id,
+    )
+    assert response['status'] == 'cancelled'