switch to a notifications class [notifications_class]

Author: hjwp

src/allocation/adapters/email.py

@@ -0,0 +1,28 @@
+# pylint: disable=too-few-public-methods
+import abc
+import smtplib
+from allocation import config
+
+
+class AbstractNotifications(abc.ABC):
+    @abc.abstractmethod
+    def send(self, destination, message):
+        raise NotImplementedError
+
+
+DEFAULT_HOST = config.get_email_host_and_port()["host"]
+DEFAULT_PORT = config.get_email_host_and_port()["port"]
+
+
+class EmailNotifications(AbstractNotifications):
+    def __init__(self, smtp_host=DEFAULT_HOST, port=DEFAULT_PORT):
+        self.server = smtplib.SMTP(smtp_host, port=port)
+        self.server.noop()
+
+    def send(self, destination, message):
+        msg = f"Subject: allocation service notification\n{message}"
+        self.server.sendmail(
+            from_addr="allocations@example.com",
+            to_addrs=[destination],
+            msg=msg,
+        )

src/allocation/adapters/notifications.py

@@ -1,20 +1,27 @@
 import inspect
 from typing import Callable
-from allocation.adapters import email, orm, redis_eventpublisher
+from allocation.adapters import orm, redis_eventpublisher
+from allocation.adapters.notifications import (
+    AbstractNotifications,
+    EmailNotifications,
+)
 from allocation.service_layer import handlers, messagebus, unit_of_work
 
 
 def bootstrap(
     start_orm: bool = True,
     uow: unit_of_work.AbstractUnitOfWork = unit_of_work.SqlAlchemyUnitOfWork(),
-    send_mail: Callable = email.send,
+    notifications: AbstractNotifications = None,
     publish: Callable = redis_eventpublisher.publish,
 ) -> messagebus.MessageBus:
 
+    if notifications is None:
+        notifications = EmailNotifications()
+
     if start_orm:
         orm.start_mappers()
 
-    dependencies = {"uow": uow, "send_mail": send_mail, "publish": publish}
+    dependencies = {"uow": uow, "notifications": notifications, "publish": publish}
     injected_event_handlers = {
         event_type: [
             inject_dependencies(handler, dependencies)

src/allocation/bootstrap.py

@@ -19,3 +19,10 @@ def get_redis_host_and_port():
     host = os.environ.get("REDIS_HOST", "localhost")
     port = 63791 if host == "localhost" else 6379
     return dict(host=host, port=port)
+
+
+def get_email_host_and_port():
+    host = os.environ.get("EMAIL_HOST", "localhost")
+    port = 11025 if host == "localhost" else 1025
+    http_port = 18025 if host == "localhost" else 8025
+    return dict(host=host, port=port, http_port=http_port)

src/allocation/config.py

@@ -6,6 +6,7 @@
 from allocation.domain.model import OrderLine
 
 if TYPE_CHECKING:
+    from allocation.adapters import notifications
     from . import unit_of_work
 
 
@@ -61,9 +62,9 @@ def change_batch_quantity(
 
 def send_out_of_stock_notification(
     event: events.OutOfStock,
-    send_mail: Callable,
+    notifications: notifications.AbstractNotifications,
 ):
-    send_mail(
+    notifications.send(
         "stock@made.com",
         f"Out of stock for {event.sku}",
     )