Merge pull request #1946 from dedis/work-be1-arnauds5-federation-data…

…-exchange

[BE1] Federation Data Exchange

be1-go/internal/handler/channel/channel.go

@@ -56,6 +56,7 @@ const (
 	FederationActionInit             = "init"
 	FederationActionExpect           = "expect"
 	FederationActionResult           = "result"
+	FederationActionTokensExchange   = "tokens_exchange"
 
 	ChirpObject             = "chirp"
 	ChirpActionAdd          = "add"

be1-go/internal/handler/channel/federation/hfederation/federation.go

@@ -17,7 +17,6 @@ import (
 	"popstellar/internal/handler/jsonrpc/mjsonrpc"
 	"popstellar/internal/handler/message/mmessage"
 	"popstellar/internal/handler/method/publish/mpublish"
-	"popstellar/internal/handler/method/subscribe/msubscribe"
 	"popstellar/internal/handler/query/mquery"
 	"popstellar/internal/network/socket"
 	"popstellar/internal/validation"
@@ -44,7 +43,18 @@ type Subscribers interface {
 	SendToAll(buf []byte, channel string) error
 }
 
+type Sockets interface {
+	Upsert(socket socket.Socket)
+}
+
+type Config interface {
+	GetServerInfo() (string, string, string, error)
+}
+
 type Repository interface {
+	// HasMessage returns true if the message already exists.
+	HasMessage(messageID string) (bool, error)
+
 	// GetOrganizerPubKey returns the organizer public key of a LAO.
 	GetOrganizerPubKey(laoID string) (kyber.Point, error)
 
@@ -70,24 +80,45 @@ type Repository interface {
 }
 
 type Handler struct {
-	hub    Hub
-	subs   Subscribers
-	db     Repository
-	schema *validation.SchemaValidator
-	log    zerolog.Logger
+	hub     Hub
+	subs    Subscribers
+	sockets Sockets
+	conf    Config
+	db      Repository
+	schema  *validation.SchemaValidator
+	log     zerolog.Logger
 }
 
-func New(hub Hub, subs Subscribers, db Repository, schema *validation.SchemaValidator, log zerolog.Logger) *Handler {
+func New(hub Hub, subs Subscribers, sockets Sockets, conf Config,
+	db Repository, schema *validation.SchemaValidator,
+	log zerolog.Logger) *Handler {
 	return &Handler{
-		hub:    hub,
-		subs:   subs,
-		db:     db,
-		schema: schema,
-		log:    log.With().Str("module", "federation").Logger(),
+		hub:     hub,
+		subs:    subs,
+		sockets: sockets,
+		conf:    conf,
+		db:      db,
+		schema:  schema,
+		log:     log.With().Str("module", "federation").Logger(),
 	}
 }
 
-func (h *Handler) Handle(channelPath string, msg mmessage.Message) error {
+func (h *Handler) Handle(channelPath string, msg mmessage.Message,
+	socket socket.Socket) error {
+	err := msg.VerifyMessage()
+	if err != nil {
+		return err
+	}
+
+	alreadyExist, err := h.db.HasMessage(msg.MessageID)
+	if err != nil {
+		return err
+	}
+
+	if alreadyExist {
+		return nil
+	}
+
 	jsonData, err := base64.URLEncoding.DecodeString(msg.Data)
 	if err != nil {
 		return errors.NewInvalidMessageFieldError("failed to decode message data: %v", err)
@@ -115,9 +146,11 @@ func (h *Handler) Handle(channelPath string, msg mmessage.Message) error {
 	case channel.FederationActionExpect:
 		err = h.handleExpect(msg, channelPath)
 	case channel.FederationActionChallenge:
-		err = h.handleChallenge(msg, channelPath)
+		err = h.handleChallenge(msg, channelPath, socket)
 	case channel.FederationActionResult:
 		err = h.handleResult(msg, channelPath)
+	case channel.FederationActionTokensExchange:
+		err = h.handleTokensExchange(msg, channelPath)
 	default:
 		err = errors.NewInvalidMessageFieldError("failed to Handle %s#%s, invalid object#action", object, action)
 	}
@@ -192,6 +225,11 @@ func (h *Handler) handleExpect(msg mmessage.Message, channelPath string) error {
 		return err
 	}
 
+	err = federationExpect.ChallengeMsg.VerifyMessage()
+	if err != nil {
+		return err
+	}
+
 	var challenge mfederation.FederationChallenge
 	err = federationExpect.ChallengeMsg.UnmarshalData(&challenge)
 	if err != nil {
@@ -213,9 +251,6 @@ func (h *Handler) handleExpect(msg mmessage.Message, channelPath string) error {
 		return err
 	}
 
-	remoteChannel := fmt.Sprintf(channelPattern, federationExpect.LaoId)
-	_ = h.subs.AddChannel(remoteChannel)
-
 	return h.db.StoreMessageAndData(channelPath, msg)
 }
 
@@ -257,45 +292,29 @@ func (h *Handler) handleInit(msg mmessage.Message, channelPath string) error {
 		return err
 	}
 
-	remote, err := h.connectTo(federationInit.ServerAddress)
-	if err != nil {
-		return err
-	}
-
-	//Force the remote server to be subscribed to /root/<remote_lao>/federation
 	remoteChannel := fmt.Sprintf(channelPattern, federationInit.LaoId)
-	_ = h.subs.AddChannel(remoteChannel)
-	err = h.subs.Subscribe(remoteChannel, remote)
-	if err != nil {
-		return err
+	if h.isOnSameServer(federationInit.ServerAddress) {
+		// In the edge case where the two LAOs are on the same server,
+		// there is no need to create a websocket connection to the other
+		// server and message from one "server" to the "other" could be
+		// directly handled.
+		// In that case the ack result of the federation_init will be sent
+		// only after any federation_result sent when handling the challenge.
+		_ = h.handleChallenge(federationInit.ChallengeMsg, remoteChannel, nil)
+		return nil
 	}
 
-	subscribeMsg := msubscribe.Subscribe{
-		Base: mquery.Base{
-			JSONRPCBase: mjsonrpc.JSONRPCBase{
-				JSONRPC: "2.0",
-			},
-			Method: "subscribe",
-		},
-		Params: msubscribe.SubscribeParams{Channel: channelPath},
-	}
-
-	subscribeBytes, err := json.Marshal(subscribeMsg)
-	if err != nil {
-		return errors.NewJsonMarshalError(err.Error())
-	}
-
-	// Subscribe to /root/<local_lao>/federation on the remote server
-	err = h.subs.SendToAll(subscribeBytes, remoteChannel)
+	remote, err := h.connectTo(federationInit.ServerAddress)
 	if err != nil {
 		return err
 	}
 
-	// send the challenge to a channelPath where the remote server is subscribed to
-	return h.publishTo(federationInit.ChallengeMsg, remoteChannel)
+	// send the challenge to the remote channelPath on the remote socket
+	return h.publishTo(federationInit.ChallengeMsg, remoteChannel, remote)
 }
 
-func (h *Handler) handleChallenge(msg mmessage.Message, channelPath string) error {
+func (h *Handler) handleChallenge(msg mmessage.Message, channelPath string,
+	socket socket.Socket) error {
 	var federationChallenge mfederation.FederationChallenge
 	err := msg.UnmarshalData(&federationChallenge)
 	if err != nil {
@@ -340,13 +359,26 @@ func (h *Handler) handleChallenge(msg mmessage.Message, channelPath string) erro
 		return err
 	}
 
-	// publish the FederationResult to the other server
 	remoteChannel := fmt.Sprintf(channelPattern, federationExpect.LaoId)
-	err = h.publishTo(resultMsg, remoteChannel)
-	if err != nil {
-		return err
+	if h.isOnSameServer(federationExpect.ServerAddress) || socket == nil {
+		// In the edge case where the two LAOs are on the same server, the
+		// result message would already be stored and handleResult will not be
+		// called => broadcast the result to both federation channels directly.
+		_ = h.db.StoreMessageAndData(remoteChannel, resultMsg)
+		_ = h.subs.BroadcastToAllClients(resultMsg, remoteChannel)
+	} else {
+		// publish the FederationResult to the other server
+		err = h.publishTo(resultMsg, remoteChannel, socket)
+		if err != nil {
+			return err
+		}
+
+		// Add the socket to the list of server sockets
+		h.sockets.Upsert(socket)
 	}
 
+	h.log.Info().Msgf("A federation was successfully")
+
 	// broadcast the FederationResult to the local organizer
 	return h.subs.BroadcastToAllClients(resultMsg, channelPath)
 }
@@ -405,6 +437,26 @@ func (h *Handler) handleResult(msg mmessage.Message, channelPath string) error {
 	return h.subs.BroadcastToAllClients(msg, channelPath)
 }
 
+func (h *Handler) handleTokensExchange(msg mmessage.Message, channelPath string) error {
+	var tokensExchange mfederation.FederationTokensExchange
+	err := msg.UnmarshalData(&tokensExchange)
+	if err != nil {
+		return err
+	}
+
+	err = h.verifyLocalOrganizer(msg, channelPath)
+	if err != nil {
+		return err
+	}
+
+	err = h.db.StoreMessageAndData(channelPath, msg)
+	if err != nil {
+		return err
+	}
+
+	return h.subs.BroadcastToAllClients(msg, channelPath)
+}
+
 func (h *Handler) getOrganizerPk(federationChannel string) (string, error) {
 	laoChannel := strings.TrimSuffix(federationChannel, "/federation")
 
@@ -448,6 +500,17 @@ func (h *Handler) verifyLocalOrganizer(msg mmessage.Message, channelPath string)
 	return nil
 }
 
+func (h *Handler) isOnSameServer(address string) bool {
+	_, clientServerAddress, serverServerAddress, _ := h.conf.GetServerInfo()
+
+	isSameAddress := address == clientServerAddress || address == serverServerAddress
+
+	h.log.Info().Msgf("isOnSameServer=%v, remote=%s, client=%s, server=%s",
+		isSameAddress, address, clientServerAddress, serverServerAddress)
+
+	return isSameAddress
+}
+
 func (h *Handler) connectTo(serverAddress string) (socket.Socket, error) {
 	ws, _, err := websocket.DefaultDialer.Dial(serverAddress, nil)
 	if err != nil {
@@ -459,14 +522,15 @@ func (h *Handler) connectTo(serverAddress string) (socket.Socket, error) {
 	wg := h.hub.GetWaitGroup()
 	stopChan := h.hub.GetStopChan()
 
-	client := socket.NewClientSocket(messageChan, closedSockets, ws, wg, stopChan, h.log)
+	server := socket.NewServerSocket(messageChan, closedSockets, ws, wg, stopChan, h.log)
+	h.sockets.Upsert(server)
 
 	wg.Add(2)
 
-	go client.WritePump()
-	go client.ReadPump()
+	go server.WritePump()
+	go server.ReadPump()
 
-	return client, nil
+	return server, nil
 }
 
 func (h *Handler) createMessage(data channel.MessageData) (mmessage.Message, error) {
@@ -505,13 +569,14 @@ func (h *Handler) createMessage(data channel.MessageData) (mmessage.Message, err
 	return msg, nil
 }
 
-func (h *Handler) publishTo(msg mmessage.Message, channelPath string) error {
+func (h *Handler) publishTo(msg mmessage.Message, channelPath string,
+	socket socket.Socket) error {
 	publishMsg := mpublish.Publish{
 		Base: mquery.Base{
 			JSONRPCBase: mjsonrpc.JSONRPCBase{
 				JSONRPC: "2.0",
 			},
-			Method: "publish",
+			Method: mquery.MethodPublish,
 		},
 		Params: mpublish.PublishParams{
 			Channel: channelPath,
@@ -524,5 +589,6 @@ func (h *Handler) publishTo(msg mmessage.Message, channelPath string) error {
 		return errors.NewJsonMarshalError(err.Error())
 	}
 
-	return h.subs.SendToAll(publishBytes, channelPath)
+	socket.Send(publishBytes)
+	return nil
 }