Initial Store & Forward Implementation (#2917)

This adds store & forward relays into dendrite for p2p.
A few things have changed:
- new relay api serves new http endpoints for s&f federation
- updated outbound federation queueing which will attempt to forward
using s&f if appropriate
- database entries to track s&f relays for other nodes

federationapi/storage/sqlite3/storage.go

@@ -1,5 +1,4 @@
-// Copyright 2017-2018 New Vector Ltd
-// Copyright 2019-2020 The Matrix.org Foundation C.I.C.
+// Copyright 2022 The Matrix.org Foundation C.I.C.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -61,6 +60,14 @@ func NewDatabase(base *base.BaseDendrite, dbProperties *config.DatabaseOptions,
 	if err != nil {
 		return nil, err
 	}
+	assumedOffline, err := NewSQLiteAssumedOfflineTable(d.db)
+	if err != nil {
+		return nil, err
+	}
+	relayServers, err := NewSQLiteRelayServersTable(d.db)
+	if err != nil {
+		return nil, err
+	}
 	outboundPeeks, err := NewSQLiteOutboundPeeksTable(d.db)
 	if err != nil {
 		return nil, err
@@ -103,6 +110,8 @@ func NewDatabase(base *base.BaseDendrite, dbProperties *config.DatabaseOptions,
 		FederationQueueEDUs:      queueEDUs,
 		FederationQueueJSON:      queueJSON,
 		FederationBlacklist:      blacklist,
+		FederationAssumedOffline: assumedOffline,
+		FederationRelayServers:   relayServers,
 		FederationOutboundPeeks:  outboundPeeks,
 		FederationInboundPeeks:   inboundPeeks,
 		NotaryServerKeysJSON:     notaryKeys,