Implement ExtraPublicRoomsProvider for p2p demos (#1180)

* Change API and rename to ExtraPublicRoomsProvider

* Make dendritejs work again

* Maybe make libp2p demo work again

* Linting

cmd/dendrite-demo-libp2p/main.go

@@ -1,6 +1,4 @@
-// Copyright 2017 Vector Creations Ltd
-// Copyright 2018 New Vector Ltd
-// Copyright 2019-2020 The Matrix.org Foundation C.I.C.
+// Copyright 2020 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.
@@ -162,13 +160,12 @@ func main() {
 		&base.Base, federation, rsAPI, keyRing,
 	)
 	rsAPI.SetFederationSenderAPI(fsAPI)
-	/* TODO:
-	publicRoomsDB, err := storage.NewPublicRoomsServerDatabaseWithPubSub(string(base.Base.Cfg.Database.PublicRoomsAPI), base.LibP2PPubsub, cfg.Matrix.ServerName)
-	if err != nil {
-		logrus.WithError(err).Panicf("failed to connect to public rooms db")
-	}
-	*/
 	stateAPI := currentstateserver.NewInternalAPI(base.Base.Cfg, base.Base.KafkaConsumer)
+	provider := newPublicRoomsProvider(base.LibP2PPubsub, rsAPI, stateAPI)
+	err = provider.Start()
+	if err != nil {
+		panic("failed to create new public rooms provider: " + err.Error())
+	}
 
 	monolith := setup.Monolith{
 		Config:        base.Base.Cfg,
@@ -180,13 +177,14 @@ func main() {
 		KafkaConsumer: base.Base.KafkaConsumer,
 		KafkaProducer: base.Base.KafkaProducer,
 
-		AppserviceAPI:       asAPI,
-		EDUInternalAPI:      eduInputAPI,
-		FederationSenderAPI: fsAPI,
-		RoomserverAPI:       rsAPI,
-		ServerKeyAPI:        serverKeyAPI,
-		StateAPI:            stateAPI,
-		UserAPI:             userAPI,
+		AppserviceAPI:          asAPI,
+		EDUInternalAPI:         eduInputAPI,
+		FederationSenderAPI:    fsAPI,
+		RoomserverAPI:          rsAPI,
+		ServerKeyAPI:           serverKeyAPI,
+		StateAPI:               stateAPI,
+		UserAPI:                userAPI,
+		ExtPublicRoomsProvider: provider,
 	}
 	monolith.AddAllPublicRoutes(base.Base.PublicAPIMux)
 

cmd/dendrite-demo-libp2p/publicrooms.go

@@ -0,0 +1,156 @@
+// Copyright 2020 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.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package main
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"sync"
+	"sync/atomic"
+	"time"
+
+	currentstateAPI "github.com/matrix-org/dendrite/currentstateserver/api"
+	roomserverAPI "github.com/matrix-org/dendrite/roomserver/api"
+
+	pubsub "github.com/libp2p/go-libp2p-pubsub"
+	"github.com/matrix-org/gomatrixserverlib"
+	"github.com/matrix-org/util"
+)
+
+const MaintenanceInterval = time.Second * 10
+
+type discoveredRoom struct {
+	time time.Time
+	room gomatrixserverlib.PublicRoom
+}
+
+type publicRoomsProvider struct {
+	pubsub           *pubsub.PubSub
+	topic            *pubsub.Topic
+	subscription     *pubsub.Subscription
+	foundRooms       map[string]discoveredRoom // additional rooms we have learned about from the DHT
+	foundRoomsMutex  sync.RWMutex              // protects foundRooms
+	maintenanceTimer *time.Timer               //
+	roomsAdvertised  atomic.Value              // stores int
+	rsAPI            roomserverAPI.RoomserverInternalAPI
+	stateAPI         currentstateAPI.CurrentStateInternalAPI
+}
+
+func newPublicRoomsProvider(ps *pubsub.PubSub, rsAPI roomserverAPI.RoomserverInternalAPI, stateAPI currentstateAPI.CurrentStateInternalAPI) *publicRoomsProvider {
+	return &publicRoomsProvider{
+		foundRooms: make(map[string]discoveredRoom),
+		pubsub:     ps,
+		rsAPI:      rsAPI,
+		stateAPI:   stateAPI,
+	}
+}
+
+func (p *publicRoomsProvider) Start() error {
+	if topic, err := p.pubsub.Join("/matrix/publicRooms"); err != nil {
+		return err
+	} else if sub, err := topic.Subscribe(); err == nil {
+		p.topic = topic
+		p.subscription = sub
+		go p.MaintenanceTimer()
+		go p.FindRooms()
+		p.roomsAdvertised.Store(0)
+	} else {
+		return err
+	}
+	return nil
+}
+
+func (p *publicRoomsProvider) MaintenanceTimer() {
+	if p.maintenanceTimer != nil && !p.maintenanceTimer.Stop() {
+		<-p.maintenanceTimer.C
+	}
+	p.Interval()
+}
+
+func (p *publicRoomsProvider) Interval() {
+	p.foundRoomsMutex.Lock()
+	for k, v := range p.foundRooms {
+		if time.Since(v.time) > time.Minute {
+			delete(p.foundRooms, k)
+		}
+	}
+	p.foundRoomsMutex.Unlock()
+	if err := p.AdvertiseRooms(); err != nil {
+		fmt.Println("Failed to advertise room in DHT:", err)
+	}
+	p.foundRoomsMutex.RLock()
+	defer p.foundRoomsMutex.RUnlock()
+	fmt.Println("Found", len(p.foundRooms), "room(s), advertised", p.roomsAdvertised.Load(), "room(s)")
+	p.maintenanceTimer = time.AfterFunc(MaintenanceInterval, p.Interval)
+}
+
+func (p *publicRoomsProvider) AdvertiseRooms() error {
+	ctx := context.Background()
+	var queryRes roomserverAPI.QueryPublishedRoomsResponse
+	// Query published rooms on our server. This will not invoke clientapi.ExtraPublicRoomsProvider
+	err := p.rsAPI.QueryPublishedRooms(ctx, &roomserverAPI.QueryPublishedRoomsRequest{}, &queryRes)
+	if err != nil {
+		util.GetLogger(ctx).WithError(err).Error("QueryPublishedRooms failed")
+		return err
+	}
+	ourRooms, err := currentstateAPI.PopulatePublicRooms(ctx, queryRes.RoomIDs, p.stateAPI)
+	if err != nil {
+		util.GetLogger(ctx).WithError(err).Error("PopulatePublicRooms failed")
+		return err
+	}
+	advertised := 0
+	for _, room := range ourRooms {
+		if j, err := json.Marshal(room); err == nil {
+			if err := p.topic.Publish(context.TODO(), j); err != nil {
+				fmt.Println("Failed to publish public room:", err)
+			} else {
+				advertised++
+			}
+		}
+	}
+
+	p.roomsAdvertised.Store(advertised)
+	return nil
+}
+
+func (p *publicRoomsProvider) FindRooms() {
+	for {
+		msg, err := p.subscription.Next(context.Background())
+		if err != nil {
+			continue
+		}
+		received := discoveredRoom{
+			time: time.Now(),
+		}
+		if err := json.Unmarshal(msg.Data, &received.room); err != nil {
+			fmt.Println("Unmarshal error:", err)
+			continue
+		}
+		fmt.Printf("received %+v \n", received)
+		p.foundRoomsMutex.Lock()
+		p.foundRooms[received.room.RoomID] = received
+		p.foundRoomsMutex.Unlock()
+	}
+}
+
+func (p *publicRoomsProvider) Rooms() (rooms []gomatrixserverlib.PublicRoom) {
+	p.foundRoomsMutex.RLock()
+	defer p.foundRoomsMutex.RUnlock()
+	for _, dr := range p.foundRooms {
+		rooms = append(rooms, dr.room)
+	}
+	return
+}