Include hashes of previous pdus when referencing them

3 files changed, 14 insertions, 11 deletions

diff --git a/synapse/federation/pdu_codec.py b/synapse/federation/pdu_codec.py
index bcac5f9ae8..11fd7264b3 100644
--- a/synapse/federation/pdu_codec.py
+++ b/synapse/federation/pdu_codec.py
@@ -45,9 +45,7 @@ class PduCodec(object):
         kwargs["event_id"] = encode_event_id(pdu.pdu_id, pdu.origin)
         kwargs["room_id"] = pdu.context
         kwargs["etype"] = pdu.pdu_type
-        kwargs["prev_events"] = [
-            encode_event_id(p[0], p[1]) for p in pdu.prev_pdus
-        ]
+        kwargs["prev_pdus"] = pdu.prev_pdus
 
         if hasattr(pdu, "prev_state_id") and hasattr(pdu, "prev_state_origin"):
             kwargs["prev_state"] = encode_event_id(
@@ -78,11 +76,8 @@ class PduCodec(object):
         d["context"] = event.room_id
         d["pdu_type"] = event.type
 
-        if hasattr(event, "prev_events"):
-            d["prev_pdus"] = [
-                decode_event_id(e, self.server_name)
-                for e in event.prev_events
-            ]
+        if hasattr(event, "prev_pdus"):
+            d["prev_pdus"] = event.prev_pdus
 
         if hasattr(event, "prev_state"):
             d["prev_state_id"], d["prev_state_origin"] = (
@@ -95,7 +90,7 @@ class PduCodec(object):
         kwargs = copy.deepcopy(event.unrecognized_keys)
         kwargs.update({
             k: v for k, v in d.items()
-            if k not in ["event_id", "room_id", "type", "prev_events"]
+            if k not in ["event_id", "room_id", "type"]
         })
 
         if "ts" not in kwargs:
diff --git a/synapse/federation/replication.py b/synapse/federation/replication.py
index 9363ac7300..788a49b8e8 100644
--- a/synapse/federation/replication.py
+++ b/synapse/federation/replication.py
@@ -443,7 +443,7 @@ class ReplicationLayer(object):
             min_depth = yield self.store.get_min_depth_for_context(pdu.context)
 
             if min_depth and pdu.depth > min_depth:
-                for pdu_id, origin in pdu.prev_pdus:
+                for pdu_id, origin, hashes in pdu.prev_pdus:
                     exists = yield self._get_persisted_pdu(pdu_id, origin)
 
                     if not exists:
diff --git a/synapse/federation/units.py b/synapse/federation/units.py
index 3518efb215..6a43007837 100644
--- a/synapse/federation/units.py
+++ b/synapse/federation/units.py
@@ -141,8 +141,16 @@ class Pdu(JsonEncodedObject):
                 for kid, sig in pdu_tuple.signatures.items()
             }
 
+            prev_pdus = []
+            for prev_pdu in pdu_tuple.prev_pdu_list:
+                prev_hashes = pdu_tuple.edge_hashes.get(prev_pdu, {})
+                prev_hashes = {
+                    alg: encode_base64(hsh) for alg, hsh in prev_hashes.items()
+                }
+                prev_pdus.append((prev_pdu[0], prev_pdu[1], prev_hashes))
+
             return Pdu(
-                prev_pdus=pdu_tuple.prev_pdu_list,
+                prev_pdus=prev_pdus,
                 **args
             )
         else: