fix: add WebSocket endpoint registration and message type tests (#20)

go.mod

@@ -22,6 +22,7 @@ require (
 	github.com/evstack/ev-node/core v1.0.0-rc.1.0.20260216131057-1da76345e4b9
 	github.com/go-kit/kit v0.13.0
 	github.com/golang/protobuf v1.5.4
+	github.com/gorilla/websocket v1.5.3
 	github.com/grpc-ecosystem/grpc-gateway v1.16.0
 	github.com/hashicorp/go-metrics v0.5.4
 	github.com/ipfs/go-datastore v0.9.1
@@ -154,7 +155,6 @@ require (
 	github.com/google/uuid v1.6.0 // indirect
 	github.com/gorilla/handlers v1.5.2 // indirect
 	github.com/gorilla/mux v1.8.1 // indirect
-	github.com/gorilla/websocket v1.5.3 // indirect
 	github.com/grpc-ecosystem/go-grpc-middleware v1.4.0 // indirect
 	github.com/grpc-ecosystem/grpc-gateway/v2 v2.27.7 // indirect
 	github.com/gsterjov/go-libsecret v0.0.0-20161001094733-a6f4afe4910c // indirect

pkg/rpc/server.go

@@ -11,7 +11,9 @@ import (
 	"cosmossdk.io/log"
 	cmtcfg "github.com/cometbft/cometbft/config"
 	cmtlog "github.com/cometbft/cometbft/libs/log"
+	cmtpubsub "github.com/cometbft/cometbft/libs/pubsub"
 	rpcserver "github.com/cometbft/cometbft/rpc/jsonrpc/server"
+	cmttypes "github.com/cometbft/cometbft/types"
 	servercmtlog "github.com/cosmos/cosmos-sdk/server/log"
 	"github.com/rs/cors"
 	"golang.org/x/net/netutil"
@@ -23,11 +25,13 @@ import (
 func NewRPCServer(
 	cfg *cmtcfg.RPCConfig,
 	logger log.Logger,
+	eventBus *cmttypes.EventBus,
 ) *RPCServer {
 	cmtLogger := servercmtlog.CometLoggerWrapper{Logger: logger}
 	return &RPCServer{
-		config: cfg,
-		logger: cmtLogger,
+		config:   cfg,
+		logger:   cmtLogger,
+		eventBus: eventBus,
 	}
 }
 
@@ -38,13 +42,31 @@ type RPCServer struct {
 	httpHandler http.Handler
 	server      http.Server
 	logger      cmtlog.Logger
+	eventBus    *cmttypes.EventBus
 }
 
 // Start starts the RPC server.
 func (r *RPCServer) Start() error {
 	return r.startRPC()
 }
 
+// startRPC starts the RPC server and registers all HTTP, JSON-RPC, and
+// WebSocket endpoints.
+//
+// WebSocket support (issue #20, RFC 6455 §11.8):
+//
+// CometBFT's RegisterRPCFuncs only registers:
+//   - GET/POST /<method>  — per-method HTTP handlers
+//   - POST /              — batch JSON-RPC handler (HTTP only; no WS upgrade)
+//
+// WebSocket connectivity is provided by a separate WebsocketManager registered
+// explicitly at /websocket. Message-type handling is delegated to CometBFT's
+// wsConnection (gorilla/websocket-based):
+//   - Text   (0x1): JSON-RPC request → method dispatch → JSON response
+//   - Binary (0x2): JSON decode attempted; fails with a parse-error response
+//   - Close  (0x8): connection closed cleanly via IsCloseError check
+//   - Ping   (0x9): pong sent automatically by gorilla/websocket default handler
+//   - Pong   (0xA): resets the read deadline (handled via SetPongHandler)
 func (r *RPCServer) startRPC() error {
 	if r.config.ListenAddress == "" {
 		r.logger.Info("listen address not specified - RPC will not be exposed")
@@ -64,6 +86,23 @@ func (r *RPCServer) startRPC() error {
 
 	mux := http.NewServeMux()
 	rpcserver.RegisterRPCFuncs(mux, core.Routes, r.logger)
+
+	// RegisterRPCFuncs does not register a WebSocket endpoint.
+	// We must register it separately so clients can connect via /websocket.
+	wmLogger := r.logger.With("protocol", "websocket")
+	wm := rpcserver.NewWebsocketManager(
+		core.Routes,
+		rpcserver.OnDisconnect(func(remoteAddr string) {
+			err := r.eventBus.UnsubscribeAll(context.Background(), remoteAddr)
+			if err != nil && err != cmtpubsub.ErrSubscriptionNotFound {
+				wmLogger.Error("Failed to unsubscribe addr from events", "addr", remoteAddr, "err", err)
+			}
+		}),
+		rpcserver.ReadLimit(r.config.MaxBodyBytes),
+	)
+	wm.SetLogger(wmLogger)
+	mux.HandleFunc("/websocket", wm.WebsocketHandler)
+
 	r.httpHandler = mux
 
 	if r.config.MaxOpenConnections != 0 {