Attempt to fix some handle_send issues

It seems sometimes AP deliveries are failing due to
an odd exception where assigning a "to" to the
payload fails with lxml related things. This seems
to indicate that some payload variable is leaking from
the diaspora payload generating to the activitypub code.

Try to ensure this wouldn't be possible to happen and
add some error context for Sentry to better identify
why this would happen, if this commit doesn't fix it.

federation/outbound.py

@@ -149,6 +149,7 @@ def handle_send(
 
     # Generate payloads and collect urls
     for recipient in unique_recipients:
+        payload = None
         endpoint = recipient["endpoint"]
         fid = recipient["fid"]
         public_key = recipient.get("public_key")
@@ -157,7 +158,9 @@ def handle_send(
         protocol = recipient["protocol"]
         public = recipient["public"]
 
-        if protocol == "activitypub" and not skip_ready_payload["activitypub"]:
+        if protocol == "activitypub":
+            if skip_ready_payload["activitypub"]:
+                continue
             try:
                 if not ready_payloads[protocol]["payload"]:
                     try:
@@ -169,6 +172,7 @@ def handle_send(
                         # No point continuing for this protocol
                         skip_ready_payload["activitypub"] = True
                         logger.warning("handle_send - skipping activitypub due to failure to generate payload: %s", ex)
+                        continue
                 payload = copy.copy(ready_payloads[protocol]["payload"])
                 if public:
                     payload["to"] = [NAMESPACE_PUBLIC]
@@ -184,6 +188,16 @@ def handle_send(
             except Exception:
                 logger.error(
                     "handle_send - failed to generate payload for %s, %s: %s", fid, endpoint, traceback.format_exc(),
+                    extra={
+                        "recipient": recipient,
+                        "unique_recipients": unique_recipients,
+                        "payload": payload,
+                        "payloads": payloads,
+                        "ready_payloads": ready_payloads,
+                        "entity": entity,
+                        "author_user": author_user,
+                        "parent_user": parent_user,
+                    }
                 )
                 continue
             payloads.append({
@@ -209,6 +223,7 @@ def handle_send(
                         # No point continuing for this protocol
                         skip_ready_payload["diaspora"] = True
                         logger.warning("handle_send - skipping diaspora due to failure to generate payload: %s", ex)
+                        continue
                 ready_payloads["diaspora"]["urls"].add(endpoint)
             else:
                 if not public_key:
@@ -219,7 +234,7 @@ def handle_send(
                 try:
                     payload = handle_create_payload(
                         entity, author_user, "diaspora", to_user_key=public_key, parent_user=parent_user,
-                        payload_logger = payload_logger,
+                        payload_logger=payload_logger,
                     )
                     payload = json.dumps(payload)
                 except Exception as ex: