3 files changed, 32 insertions, 3 deletions
diff --git a/synapse/events/__init__.py b/synapse/events/__init__.py
index 7103b937af..98d7f0e324 100644
--- a/synapse/events/__init__.py
+++ b/synapse/events/__init__.py
@@ -97,6 +97,7 @@ class EventBase(object):
     origin_server_ts = _event_dict_property("origin_server_ts")
     prev_events = _event_dict_property("prev_events")
     prev_state = _event_dict_property("prev_state")
+    redacts = _event_dict_property("redacts")
     room_id = _event_dict_property("room_id")
     sender = _event_dict_property("sender")
     state_key = _event_dict_property("state_key")
diff --git a/synapse/events/builder.py b/synapse/events/builder.py
index 642264e9f3..9579b1fe8b 100644
--- a/synapse/events/builder.py
+++ b/synapse/events/builder.py
@@ -19,11 +19,18 @@ from synapse.types import EventID
 
 from synapse.util.stringutils import random_string
 
+import copy
+
 
 class EventBuilder(EventBase):
     def __init__(self, key_values={}):
+        signatures = copy.deepcopy(key_values.pop("signatures", {}))
+        unsigned = copy.deepcopy(key_values.pop("unsigned", {}))
+
         super(EventBuilder, self).__init__(
             key_values,
+            signatures=signatures,
+            unsigned=unsigned
         )
 
     def update_event_key(self, key, value):
@@ -61,9 +68,9 @@ class EventBuilderFactory(object):
         key_values.setdefault("origin", self.hostname)
         key_values.setdefault("origin_server_ts", time_now)
 
-        if "unsigned" in key_values:
-            age = key_values["unsigned"].pop("age", 0)
-            key_values["unsigned"].setdefault("age_ts", time_now - age)
+        key_values.setdefault("unsigned", {})
+        age = key_values["unsigned"].pop("age", 0)
+        key_values["unsigned"].setdefault("age_ts", time_now - age)
 
         key_values["signatures"] = {}
 
diff --git a/synapse/events/utils.py b/synapse/events/utils.py
index f5e135e3d0..6d9c9352e2 100644
--- a/synapse/events/utils.py
+++ b/synapse/events/utils.py
@@ -80,6 +80,11 @@ def prune_event(event):
 
     allowed_fields["content"] = new_content
 
+    allowed_fields["unsigned"] = {}
+
+    if "age_ts" in event.unsigned:
+        allowed_fields["unsigned"]["age_ts"] = event.unsigned["age_ts"]
+
     return type(event)(allowed_fields)
 
 
@@ -97,4 +102,20 @@ def serialize_event(hs, e):
 
     d["user_id"] = d.pop("sender", None)
 
+    if "redacted_because" in e.unsigned:
+        d["redacted_because"] = serialize_event(
+            hs, e.unsigned["redacted_because"]
+        )
+
+        del d["unsigned"]["redacted_because"]
+
+    if "redacted_by" in e.unsigned:
+        d["redacted_by"] = e.unsigned["redacted_by"]
+        del d["unsigned"]["redacted_by"]
+
+    del d["auth_events"]
+    del d["prev_events"]
+    del d["hashes"]
+    del d["signatures"]
+
     return d