Send branded HTML emails and harden SMTP2GO webhooks.

Fix campaign stuck on sending under async queue, and stop UUID ValidationError when SMTP2GO tests send "Headers Unavailable".

site/messaging/webhooks.py

@@ -4,8 +4,10 @@ from __future__ import annotations
 
 import json
 import logging
+import uuid
 from typing import Any
 
+from django.core.exceptions import ValidationError
 from django.http import HttpRequest
 
 from contacts.models import Channel, Contact
@@ -38,6 +40,45 @@ _MONICA_HEADER_KEYS = (
     "monica-message-id",
 )
 
+# SMTP2GO UI labels → canonical event strings from their docs.
+_EMAIL_EVENT_ALIASES = {
+    "bounced": "bounce",
+    "rejected": "reject",
+    "opened": "open",
+    "clicked": "click",
+    "unsubscribed": "unsubscribe",
+    "resubscribed": "resubscribe",
+}
+
+
+def _as_str(value: Any) -> str:
+    """Coerce webhook field values to a stripped string (lists / None safe)."""
+    if value is None:
+        return ""
+    if isinstance(value, (list, tuple)):
+        if not value:
+            return ""
+        value = value[0]
+    if isinstance(value, bytes):
+        value = value.decode("utf-8", errors="replace")
+    return str(value).strip()
+
+
+def _json_safe(value: Any) -> Any:
+    """Ensure ProviderEvent.payload can be stored as JSON."""
+    if value is None or isinstance(value, (str, int, float, bool)):
+        return value
+    if isinstance(value, dict):
+        return {str(k): _json_safe(v) for k, v in value.items()}
+    if isinstance(value, (list, tuple)):
+        return [_json_safe(v) for v in value]
+    return str(value)
+
+
+def _normalize_email_event(event: str) -> str:
+    event = (event or "").strip().lower()
+    return _EMAIL_EVENT_ALIASES.get(event, event)
+
 
 def parse_webhook_payload(request: HttpRequest) -> dict[str, Any]:
     """Accept JSON or form-encoded SMTP2GO webhook bodies."""
@@ -45,7 +86,7 @@ def parse_webhook_payload(request: HttpRequest) -> dict[str, Any]:
     if "application/json" in content_type:
         try:
             data = json.loads(request.body.decode() or "{}")
-        except json.JSONDecodeError:
+        except (json.JSONDecodeError, UnicodeDecodeError):
             return {}
         return data if isinstance(data, dict) else {}
     # Form-encoded (SMTP2GO default)
@@ -55,37 +96,65 @@ def parse_webhook_payload(request: HttpRequest) -> dict[str, Any]:
 def extract_monica_message_id(payload: dict[str, Any]) -> str:
     """Pull our correlation id from flat keys or a nested headers object."""
     for key in _MONICA_HEADER_KEYS:
-        value = payload.get(key)
+        value = _as_str(payload.get(key))
         if value:
-            return str(value).strip()
+            return value
 
     headers = payload.get("headers") or payload.get("email_headers") or {}
     if isinstance(headers, dict):
         for key in _MONICA_HEADER_KEYS:
-            value = headers.get(key)
+            value = _as_str(headers.get(key))
             if value:
-                return str(value).strip()
+                return value
         # Case-insensitive scan
         lower_map = {str(k).lower(): v for k, v in headers.items()}
         for key in _MONICA_HEADER_KEYS:
-            value = lower_map.get(key.lower())
+            value = _as_str(lower_map.get(key.lower()))
             if value:
-                return str(value).strip()
+                return value
+    elif isinstance(headers, list):
+        # Some ESP shapes send [["X-Monica-Message-Id", "..."], ...]
+        for item in headers:
+            if isinstance(item, (list, tuple)) and len(item) >= 2:
+                if _as_str(item[0]).lower() in {
+                    k.lower() for k in _MONICA_HEADER_KEYS
+                }:
+                    value = _as_str(item[1])
+                    if value:
+                        return value
+            elif isinstance(item, str) and ":" in item:
+                name, _, rest = item.partition(":")
+                if name.strip().lower() in {k.lower() for k in _MONICA_HEADER_KEYS}:
+                    value = rest.strip()
+                    if value:
+                        return value
     return ""
 
 
+def _message_by_pk(pk: str) -> Message | None:
+    """Lookup Message by UUID pk without raising on malformed ids."""
+    try:
+        uuid.UUID(str(pk))
+    except (ValueError, AttributeError, TypeError):
+        return None
+    try:
+        return (
+            Message.objects.select_related("contact", "campaign")
+            .filter(pk=pk)
+            .first()
+        )
+    except (ValidationError, ValueError):
+        return None
+
+
 def find_message_for_email_event(payload: dict[str, Any]) -> Message | None:
     monica_id = extract_monica_message_id(payload)
     if monica_id:
-        message = (
-            Message.objects.select_related("contact", "campaign")
-            .filter(pk=monica_id)
-            .first()
-        )
+        message = _message_by_pk(monica_id)
         if message:
             return message
 
-    email_id = (payload.get("email_id") or payload.get("email-id") or "").strip()
+    email_id = _as_str(payload.get("email_id") or payload.get("email-id"))
     if email_id:
         message = (
             Message.objects.select_related("contact", "campaign")
@@ -95,13 +164,13 @@ def find_message_for_email_event(payload: dict[str, Any]) -> Message | None:
         if message:
             return message
 
-    rcpt = (payload.get("rcpt") or "").strip().lower()
+    rcpt = _as_str(payload.get("rcpt")).lower()
     if not rcpt:
         recipients = payload.get("recipients")
         if isinstance(recipients, str) and recipients.strip():
             rcpt = recipients.split(",")[0].strip().lower()
         elif isinstance(recipients, list) and recipients:
-            rcpt = str(recipients[0]).strip().lower()
+            rcpt = _as_str(recipients[0]).lower()
 
     if not rcpt:
         return None
@@ -157,11 +226,11 @@ def _maybe_upgrade_status(message: Message, new_status: str, *, error: str = "")
 
 
 def _apply_email_event(message: Message, event: str, payload: dict[str, Any]) -> None:
-    event = (event or "").strip().lower()
-    bounce_kind = (payload.get("bounce") or "").strip().lower()
-    err = (payload.get("message") or payload.get("context") or "").strip()
+    event = _normalize_email_event(event)
+    bounce_kind = _as_str(payload.get("bounce")).lower()
+    err = _as_str(payload.get("message") or payload.get("context"))
 
-    email_id = (payload.get("email_id") or payload.get("email-id") or "").strip()
+    email_id = _as_str(payload.get("email_id") or payload.get("email-id"))
     if email_id and message.provider_message_id != email_id:
         message.provider_message_id = email_id
         message.provider = PROVIDER_EMAIL
@@ -233,7 +302,7 @@ def process_smtp2go_email_webhook(payload: dict[str, Any]) -> ProviderEvent | No
 
     Returns the stored event (even if message could not be matched).
     """
-    event = (payload.get("event") or "").strip().lower()
+    event = _normalize_email_event(_as_str(payload.get("event")))
     if not event:
         logger.warning("SMTP2GO webhook missing event: %s", payload)
         return None
@@ -253,8 +322,8 @@ def process_smtp2go_email_webhook(payload: dict[str, Any]) -> ProviderEvent | No
     return ProviderEvent.objects.create(
         message=message,
         provider=PROVIDER_EMAIL,
-        event_type=event,
-        payload=payload,
+        event_type=event[:64],
+        payload=_json_safe(payload) if isinstance(payload, dict) else {},
     )
 
 
@@ -442,11 +511,7 @@ def find_message_for_pcm_event(payload: dict[str, Any]) -> Message | None:
         ext = payload["recipient"].get("extRefNbr") or ""
     ext = str(ext).strip()
     if ext:
-        message = (
-            Message.objects.select_related("contact", "campaign")
-            .filter(pk=ext)
-            .first()
-        )
+        message = _message_by_pk(ext)
         if message:
             return message