Notifications: Improve L402 handling

cmd/loop/l402.go

@@ -73,3 +73,31 @@ func listAuth(ctx *cli.Context) error {
 	printJSON(tokens)
 	return nil
 }
+
+var fetchL402Command = cli.Command{
+	Name:  "fetchl402",
+	Usage: "fetches a new L402 authentication token from the server",
+	Description: "Fetches a new L402 authentication token from the server. " +
+		"This token is required to listen to notifications from the server, " +
+		"such as reservation notifications. If a L402 is already present in " +
+		"the store, this command is a no-op.",
+	Action: fetchL402,
+}
+
+func fetchL402(ctx *cli.Context) error {
+	client, cleanup, err := getClient(ctx)
+	if err != nil {
+		return err
+	}
+	defer cleanup()
+
+	res, err := client.FetchL402Token(
+		context.Background(), &looprpc.FetchL402TokenRequest{},
+	)
+	if err != nil {
+		return err
+	}
+
+	printRespJSON(res)
+	return nil
+}

cmd/loop/main.go

@@ -144,7 +144,7 @@ func main() {
 	}
 	app.Commands = []cli.Command{
 		loopOutCommand, loopInCommand, termsCommand,
-		monitorCommand, quoteCommand, listAuthCommand,
+		monitorCommand, quoteCommand, listAuthCommand, fetchL402Command,
 		listSwapsCommand, swapInfoCommand, getLiquidityParamsCommand,
 		setLiquidityRuleCommand, suggestSwapCommand, setParamsCommand,
 		getInfoCommand, abandonSwapCommand, reservationsCommands,

loopd/daemon.go

@@ -504,8 +504,8 @@ func (d *Daemon) initialize(withMacaroonService bool) error {
 
 	// Start the notification manager.
 	notificationCfg := &notifications.Config{
-		Client:    loop_swaprpc.NewSwapServerClient(swapClient.Conn),
-		FetchL402: swapClient.Server.FetchL402,
+		Client:       loop_swaprpc.NewSwapServerClient(swapClient.Conn),
+		CurrentToken: swapClient.L402Store.CurrentToken,
 	}
 	notificationManager := notifications.NewManager(notificationCfg)
 

loopd/perms/perms.go

@@ -77,6 +77,10 @@ var RequiredPermissions = map[string][]bakery.Op{
 		Entity: "auth",
 		Action: "read",
 	}},
+	"/looprpc.SwapClient/FetchL402Token": {{
+		Entity: "auth",
+		Action: "write",
+	}},
 	"/looprpc.SwapClient/SuggestSwaps": {{
 		Entity: "suggestions",
 		Action: "read",

loopd/swapclient_server.go

@@ -991,6 +991,21 @@ func (s *swapClientServer) GetLsatTokens(ctx context.Context,
 	return s.GetL402Tokens(ctx, req)
 }
 
+// FetchL402Token fetches a L402 Token from the server. This is required to
+// listen for server notifications such as reservations. If a token is already
+// in the local L402, nothing will happen.
+func (s *swapClientServer) FetchL402Token(ctx context.Context,
+	_ *looprpc.FetchL402TokenRequest) (*looprpc.FetchL402TokenResponse,
+	error) {
+
+	err := s.impl.Server.FetchL402(ctx)
+	if err != nil {
+		return nil, err
+	}
+
+	return &looprpc.FetchL402TokenResponse{}, nil
+}
+
 // GetInfo returns basic information about the loop daemon and details to swaps
 // from the swap store.
 func (s *swapClientServer) GetInfo(ctx context.Context,