create mailgun webhook endpoint

send message to slack channel on failure

scipost_django/SciPost_v1/settings/base.py

@@ -632,3 +632,7 @@ GITLAB_KEY = get_secret("GITLAB_KEY")
 # ORCID API
 ORCID_CLIENT_ID = get_secret("ORCID_CLIENT_ID")
 ORCID_CLIENT_SECRET = get_secret("ORCID_CLIENT_SECRET")
+
+
+# SLACK API
+SLACK_WEBHOOK_URL_MAILGUN_ALERTS = get_secret("SLACK_WEBHOOK_URL_MAILGUN_ALERTS")

scipost_django/apimail/api/views/__init__.py

@@ -25,3 +25,5 @@ from .stored_message import (
     StoredMessageUpdateReadAPIView,
     StoredMessageUpdateTagAPIView,
 )
+
+from .integrations import mailgun_webhook

scipost_django/apimail/api/views/integrations.py

+__copyright__ = "Copyright © Stichting SciPost (SciPost Foundation)"
+__license__ = "AGPL v3"
+
+import json
+from django.conf import settings
+from django.http import HttpResponse
+from django.views.decorators.csrf import csrf_exempt
+
+
+def mailgun_webhook_is_signed(timestamp, token, signature):
+    """
+    Verify the signature of a mailgun webhook.
+    """
+    import hmac
+
+    encoded_token = hmac.new(
+        settings.MAILGUN_API_KEY.encode(),
+        (timestamp + token).encode(),
+        "sha256",
+    ).hexdigest()
+
+    return encoded_token == signature
+
+
+def send_mailgun_alert_slack_message(event_data: dict):
+    """
+    Format mailgun event data and send an alert to Slack
+    """
+    import requests
+
+    event = event_data.get("event", "unknown")
+    reason = event_data.get("reason", "unknown")
+    recipient = event_data.get("message", {}).get("headers", {}).get("to", "unknown")
+    sender = event_data.get("message", {}).get("headers", {}).get("from", "unknown")
+    subject = event_data.get("message", {}).get("headers", {}).get("subject", "unknown")
+
+    message = f"[{event.upper()}] {recipient} -> {sender}\nSubject: {subject}\nReason: {reason}"
+
+    response = requests.post(
+        settings.SLACK_WEBHOOK_URL_MAILGUN_ALERTS,
+        json={"text": message},
+        headers={"Content-type": "application/json"},
+    )
+
+    return response
+
+
+@csrf_exempt
+def mailgun_webhook(request):
+    """
+    Endpoint to receive POST requests for mailgun webhook.
+    Executes custom integrations upon reception.
+    """
+
+    if request.method != "POST":
+        return HttpResponse(status=405)
+
+    data = json.loads(request.body)
+
+    if "signature" not in data:
+        return HttpResponse(status=400)
+
+    # Verify signature, return 403 if invalid
+    if not mailgun_webhook_is_signed(**data.get("signature")):
+        return HttpResponse(status=403)
+
+    # Apply custom integrations here
+    event_data = data.get("event-data", {})
+    send_mailgun_alert_slack_message(event_data)
+
+    return HttpResponse(status=200)

scipost_django/apimail/urls.py

@@ -117,5 +117,6 @@ urlpatterns = [
     path(  # /mail/attachment_file/<uuid>
         "attachment_file/<uuid:uuid>", views.attachment_file, name="attachment_file"
     ),
+    path("mailgun_webhook", apiviews.mailgun_webhook, name="mailgun_webhook"),
     path("", views.mail, name="mail"),  # /mail
 ]