feat: ENR can now be updated

waku/waku_discv5.nim

@@ -122,6 +122,17 @@ proc new*(T: type WakuDiscoveryV5,
 
   WakuDiscoveryV5.new(rng, conf, some(record))
 
+proc updateENRShards*(wd: WakuDiscoveryV5, shards: RelayShards): Result[void, cstring] =
+  let (field, value) =
+    if shards.indices.len >= 64:
+      (ShardingBitVectorEnrField, shards.toBitVector())
+    else:
+      (ShardingIndicesListEnrField, ?shards.toIndicesList())
+
+  ?wd.protocol.updateRecord([(field, value)])
+
+  ok()
+
 proc shardingPredicate*(record: Record): Option[WakuDiscv5Predicate] =
   ## Filter peers based on relay sharding information
 

waku/waku_enr/sharding.nim

@@ -108,7 +108,7 @@ func contains*(rs: RelayShards, topic: PubsubTopic|string): bool =
 
 # ENR builder extension
 
-func toIndicesList(rs: RelayShards): EnrResult[seq[byte]] =
+func toIndicesList*(rs: RelayShards): EnrResult[seq[byte]] =
   if rs.indices.len > high(uint8).int:
     return err("indices list too long")
 
@@ -137,7 +137,7 @@ func fromIndicesList(buf: seq[byte]): Result[RelayShards, string] =
 
   ok(RelayShards(cluster: cluster, indices: indices))
 
-func toBitVector(rs: RelayShards): seq[byte] =
+func toBitVector*(rs: RelayShards): seq[byte] =
   ## The value is comprised of a two-byte shard cluster index in network byte
   ## order concatenated with a 128-byte wide bit vector. The bit vector
   ## indicates which shards of the respective shard cluster the node is part