SparkPostCeleryEmailBackend for Django

dev-requirements.txt

@@ -2,4 +2,5 @@
 wheel
 twine
 Django>=1.7,<1.10
-tornado>=3.2
+tornado>=3.2
+celery>=3.1.23

sparkpost/django/email_backend.py

@@ -4,6 +4,7 @@
 from sparkpost import SparkPost
 
 from .message import SparkPostMessage
+from .tasks import send_messages
 
 
 class SparkPostEmailBackend(BaseEmailBackend):
@@ -37,3 +38,13 @@ def _send(self, message):
         params = getattr(settings, 'SPARKPOST_OPTIONS', {}).copy()
         params.update(message)
         return self.client.transmissions.send(**params)
+
+
+class SparkPostCeleryEmailBackend(SparkPostEmailBackend):
+    def send_messages(self, email_messages):
+        """
+        Send emails, returns celery result object (AsyncResult)
+        When task will be complete, it will contain integer
+        representing number of successful emails
+        """
+        return send_messages.delay(self, email_messages)

sparkpost/django/tasks.py

@@ -0,0 +1,32 @@
+from celery import chord
+from celery.task import task
+
+from .message import SparkPostMessage
+
+
+@task()
+def send_messages(obj, email_messages):
+    """
+    Celery task for 'send_messages' EmailBackend method.
+    It sends all email messages in parallel via 'send_message' task,
+    and then it reduces all results via `send_summary` task
+    (celery chord is convenient)
+    """
+    return chord(send_message.s(obj, email_message)
+                 for email_message in email_messages)(send_summary.s())
+
+
+@task()
+def send_message(obj, message):
+    try:
+        response = obj._send(SparkPostMessage(message))
+    except Exception:
+        if not obj.fail_silently:
+            raise
+    else:
+        return response['total_accepted_recipients']
+
+
+@task()
+def send_summary(send_results):
+    return sum([send_result for send_result in send_results])

tox.ini

@@ -1,16 +1,17 @@
 [tox]
-envlist = {py27,py34}-django{17,18}, py35-django{18,19}
+envlist = {py27,py34}-django{17,18}-celery, py35-django{18,19}-celery
 
 [testenv]
 deps =
     -rtest-requirements.txt
     django17: Django>=1.7,<1.8
     django18: Django>=1.8,<1.9
     django19: Django>=1.9,<1.10
+    celery: celery==3.1.23
 
 commands = py.test test/
 
-[testenv:py35-django19]
+[testenv:py35-django19-celery]
 
 commands =
     flake8 sparkpost test