plugin XEP-0277: signed flag can now be used in extra to use sign the blog post:

rel 381

sat/plugins/plugin_xep_0277.py

@@ -983,7 +983,11 @@ class XEP_0277(object):
         ):
             return None
 
-        extra = {"encrypted": True} if data.get("encrypted") else None
+        extra = {}
+        for key in ("encrypted", "signed"):
+            value = data.get(key)
+            if value is not None:
+                extra[key] = value
 
         await self._p.publish(client, service, node, [item], extra=extra)
         return item_id