implemented timeout for an initial GetSeed call.

Added RPC.Endpoint.Authority

client.go

@@ -21,7 +21,6 @@ import "google.golang.org/grpc/status"
 
 type PacketStreamClient grpc.BidiStreamingClient[Packet, Packet]
 
-type ClientConnMapByAddr = map[string]*ClientConn
 type ClientConnMap = map[uint32]*ClientConn
 type ClientPeerConnMap = map[uint32]*ClientPeerConn
 type ClientRouteMap = map[uint32]*ClientRoute
@@ -31,6 +30,8 @@ type ClientPeerCancelFuncMap = map[uint32]context.CancelFunc
 type ClientConfig struct {
 	ServerAddrs []string
 	PeerAddrs []string
+	ServerSeedTimeout int
+	ServerAuthority string // http2 :authority header
 }
 
 type ClientConfigActive struct {
@@ -54,7 +55,6 @@ type Client struct {
 	ctl        []*http.Server // control server
 
 	cts_mtx     sync.Mutex
-	cts_map_by_addr ClientConnMapByAddr
 	cts_map     ClientConnMap
 
 	wg          sync.WaitGroup
@@ -718,6 +718,20 @@ func (cts *ClientConn) ReqStop() {
 	}
 }
 
+func timed_interceptor(tmout_sec int) grpc.UnaryClientInterceptor {
+	// The client calls GetSeed() as the first call to the server.
+	// To simulate a kind of connect timeout to the server and find out an unresponsive server,
+	// Place a unary intercepter that places a new context with a timeout on the GetSeed() call.
+    return func(ctx context.Context, method string, req, reply interface{}, cc *grpc.ClientConn, invoker grpc.UnaryInvoker, opts ...grpc.CallOption) error {
+		var cancel context.CancelFunc
+		if tmout_sec > 0 && method == Hodu_GetSeed_FullMethodName {
+			ctx, cancel = context.WithTimeout(ctx, time.Duration(tmout_sec) * time.Second)
+			defer cancel()
+		}
+		return invoker(ctx, method, req, reply, cc, opts...)
+    }
+}
+
 func (cts *ClientConn) RunTask(wg *sync.WaitGroup) {
 	var psc PacketStreamClient
 	var slpctx context.Context
@@ -732,21 +746,26 @@ func (cts *ClientConn) RunTask(wg *sync.WaitGroup) {
 
 start_over:
 	cts.cfg.Index = (cts.cfg.Index + 1) % len(cts.cfg.ServerAddrs)
-	cts.cli.log.Write(cts.sid, LOG_INFO, "Connecting to server %s", cts.cfg.ServerAddrs[cts.cfg.Index])
+	cts.cli.log.Write(cts.sid, LOG_INFO, "Connecting to server[%d] %s", cts.cfg.Index, cts.cfg.ServerAddrs[cts.cfg.Index])
 	if cts.cli.rpctlscfg == nil {
 		opts = append(opts, grpc.WithTransportCredentials(insecure.NewCredentials()))
-		// TODO: can we have other authority for non-tls?
-		// if normal configuration has authority, use it (non-tls side)
-		// if notmal configuration doesn't have authori, tls has server name, use tls server name (tls side)
+		if cts.cfg.ServerAuthority != "" { opts = append(opts, grpc.WithAuthority(cts.cfg.ServerAuthority)) }
 	} else {
 		opts = append(opts, grpc.WithTransportCredentials(credentials.NewTLS(cts.cli.rpctlscfg)))
-
 		// set the http2 :authority header with tls server name defined.
-		if cts.cli.rpctlscfg.ServerName != "" { opts = append(opts, grpc.WithAuthority(cts.cli.rpctlscfg.ServerName)) }
+		if cts.cfg.ServerAuthority != "" {
+			opts = append(opts, grpc.WithAuthority(cts.cfg.ServerAuthority))
+		} else if cts.cli.rpctlscfg.ServerName != "" {
+			opts = append(opts, grpc.WithAuthority(cts.cli.rpctlscfg.ServerName))
+		}
 	}
+	if cts.cfg.ServerSeedTimeout > 0 {
+		opts = append(opts, grpc.WithUnaryInterceptor(timed_interceptor(cts.cfg.ServerSeedTimeout)))
+	}
+
 	cts.conn, err = grpc.NewClient(cts.cfg.ServerAddrs[cts.cfg.Index], opts...)
 	if err != nil {
-		cts.cli.log.Write(cts.sid, LOG_ERROR, "Failed to make client to server %s - %s", cts.cfg.ServerAddrs[cts.cfg.Index], err.Error())
+		cts.cli.log.Write(cts.sid, LOG_ERROR, "Failed to make client to server[%d] %s - %s", cts.cfg.Index, cts.cfg.ServerAddrs[cts.cfg.Index], err.Error())
 		goto reconnect_to_server
 	}
 	cts.hdc = NewHoduClient(cts.conn)
@@ -1013,7 +1032,6 @@ func NewClient(ctx context.Context, ctl_addrs []string, logger Logger, ctl_prefi
 	c.ctltlscfg = ctltlscfg
 	c.rpctlscfg = rpctlscfg
 	c.ext_svcs = make([]Service, 0, 1)
-	c.cts_map_by_addr = make(ClientConnMapByAddr)
 	c.cts_map = make(ClientConnMap)
 	c.stop_req.Store(false)
 	c.stop_chan = make(chan bool, 8)

cmd/config.go

@@ -51,8 +51,9 @@ type RPCServiceConfig struct { // rpc server-side configuration
 }
 
 type RPCEndpointConfig struct { // rpc client-side configuration
-	Authority string   `yaml:"authority"`
-	Addrs     []string `yaml:"addresses"`
+	Authority   string   `yaml:"authority"`
+	Addrs       []string `yaml:"addresses"`
+	SeedTimeout int      `yaml:"seed-timeout"`
 }
 
 type ServerConfig struct {

cmd/main.go

@@ -226,6 +226,8 @@ func client_main(ctl_addrs []string, rpc_addrs []string, peer_addrs []string, cf
 
 	cc.ServerAddrs = rpc_addrs
 	cc.PeerAddrs = peer_addrs
+	cc.ServerSeedTimeout = cfg.RPC.Endpoint.SeedTimeout
+	cc.ServerAuthority = cfg.RPC.Endpoint.Authority
 
 	c.StartService(&cc)
 	c.StartCtlService() // control channel