rpc, p2p/simulations: use github.com/gorilla/websocket (#20289)

* rpc: improve codec abstraction

rpc.ServerCodec is an opaque interface. There was only one way to get a
codec using existing APIs: rpc.NewJSONCodec. This change exports
newCodec (as NewFuncCodec) and NewJSONCodec (as NewCodec). It also makes
all codec methods non-public to avoid showing internals in godoc.

While here, remove codec options in tests because they are not
supported anymore.

* p2p/simulations: use github.com/gorilla/websocket

This package was the last remaining user of golang.org/x/net/websocket.
Migrating to the new library wasn't straightforward because it is no
longer possible to treat WebSocket connections as a net.Conn.

* vendor: delete golang.org/x/net/websocket

* rpc: fix godoc comments and run gofmt

p2p/simulations/adapters/exec.go

@@ -41,7 +41,7 @@ import (
 	"github.com/ethereum/go-ethereum/p2p"
 	"github.com/ethereum/go-ethereum/p2p/enode"
 	"github.com/ethereum/go-ethereum/rpc"
-	"golang.org/x/net/websocket"
+	"github.com/gorilla/websocket"
 )
 
 func init() {
@@ -118,7 +118,7 @@ func (e *ExecAdapter) NewNode(config *NodeConfig) (Node, error) {
 	conf.Stack.P2P.NAT = nil
 	conf.Stack.NoUSB = true
 
-	// listen on a localhost port, which we set when we
+	// Listen on a localhost port, which we set when we
 	// initialise NodeConfig (usually a random port)
 	conf.Stack.P2P.ListenAddr = fmt.Sprintf(":%d", config.Port)
 
@@ -205,17 +205,17 @@ func (n *ExecNode) Start(snapshots map[string][]byte) (err error) {
 	}
 	n.Cmd = cmd
 
-	// read the WebSocket address from the stderr logs
+	// Wait for the node to start.
 	status := <-statusC
 	if status.Err != "" {
 		return errors.New(status.Err)
 	}
-	client, err := rpc.DialWebsocket(ctx, status.WSEndpoint, "http://localhost")
+	client, err := rpc.DialWebsocket(ctx, status.WSEndpoint, "")
 	if err != nil {
 		return fmt.Errorf("can't connect to RPC server: %v", err)
 	}
 
-	// node ready :)
+	// Node ready :)
 	n.client = client
 	n.wsAddr = status.WSEndpoint
 	n.Info = status.NodeInfo
@@ -314,29 +314,35 @@ func (n *ExecNode) NodeInfo() *p2p.NodeInfo {
 
 // ServeRPC serves RPC requests over the given connection by dialling the
 // node's WebSocket address and joining the two connections
-func (n *ExecNode) ServeRPC(clientConn net.Conn) error {
-	conn, err := websocket.Dial(n.wsAddr, "", "http://localhost")
+func (n *ExecNode) ServeRPC(clientConn *websocket.Conn) error {
+	conn, _, err := websocket.DefaultDialer.Dial(n.wsAddr, nil)
 	if err != nil {
 		return err
 	}
 	var wg sync.WaitGroup
 	wg.Add(2)
-	join := func(src, dst net.Conn) {
-		defer wg.Done()
-		io.Copy(dst, src)
-		// close the write end of the destination connection
-		if cw, ok := dst.(interface {
-			CloseWrite() error
-		}); ok {
-			cw.CloseWrite()
-		} else {
-			dst.Close()
+	go wsCopy(&wg, conn, clientConn)
+	go wsCopy(&wg, clientConn, conn)
+	wg.Wait()
+	conn.Close()
+	return nil
+}
+
+func wsCopy(wg *sync.WaitGroup, src, dst *websocket.Conn) {
+	defer wg.Done()
+	for {
+		msgType, r, err := src.NextReader()
+		if err != nil {
+			return
+		}
+		w, err := dst.NextWriter(msgType)
+		if err != nil {
+			return
+		}
+		if _, err = io.Copy(w, r); err != nil {
+			return
 		}
 	}
-	go join(conn, clientConn)
-	go join(clientConn, conn)
-	wg.Wait()
-	return nil
 }
 
 // Snapshots creates snapshots of the services by calling the

p2p/simulations/adapters/inproc.go

@@ -30,6 +30,7 @@ import (
 	"github.com/ethereum/go-ethereum/p2p/enode"
 	"github.com/ethereum/go-ethereum/p2p/simulations/pipes"
 	"github.com/ethereum/go-ethereum/rpc"
+	"github.com/gorilla/websocket"
 )
 
 // SimAdapter is a NodeAdapter which creates in-memory simulation nodes and
@@ -210,13 +211,14 @@ func (sn *SimNode) Client() (*rpc.Client, error) {
 }
 
 // ServeRPC serves RPC requests over the given connection by creating an
-// in-memory client to the node's RPC server
-func (sn *SimNode) ServeRPC(conn net.Conn) error {
+// in-memory client to the node's RPC server.
+func (sn *SimNode) ServeRPC(conn *websocket.Conn) error {
 	handler, err := sn.node.RPCHandler()
 	if err != nil {
 		return err
 	}
-	handler.ServeCodec(rpc.NewJSONCodec(conn), rpc.OptionMethodInvocation|rpc.OptionSubscriptions)
+	codec := rpc.NewFuncCodec(conn, conn.WriteJSON, conn.ReadJSON)
+	handler.ServeCodec(codec, 0)
 	return nil
 }
 

p2p/simulations/adapters/types.go

@@ -33,6 +33,7 @@ import (
 	"github.com/ethereum/go-ethereum/p2p/enode"
 	"github.com/ethereum/go-ethereum/p2p/enr"
 	"github.com/ethereum/go-ethereum/rpc"
+	"github.com/gorilla/websocket"
 )
 
 // Node represents a node in a simulation network which is created by a
@@ -51,7 +52,7 @@ type Node interface {
 	Client() (*rpc.Client, error)
 
 	// ServeRPC serves RPC requests over the given connection
-	ServeRPC(net.Conn) error
+	ServeRPC(*websocket.Conn) error
 
 	// Start starts the node with the given snapshots
 	Start(snapshots map[string][]byte) error

p2p/simulations/http.go

@@ -34,8 +34,8 @@ import (
 	"github.com/ethereum/go-ethereum/p2p/enode"
 	"github.com/ethereum/go-ethereum/p2p/simulations/adapters"
 	"github.com/ethereum/go-ethereum/rpc"
+	"github.com/gorilla/websocket"
 	"github.com/julienschmidt/httprouter"
-	"golang.org/x/net/websocket"
 )
 
 // DefaultClient is the default simulation API client which expects the API
@@ -654,16 +654,20 @@ func (s *Server) Options(w http.ResponseWriter, req *http.Request) {
 	w.WriteHeader(http.StatusOK)
 }
 
+var wsUpgrade = websocket.Upgrader{
+	CheckOrigin: func(*http.Request) bool { return true },
+}
+
 // NodeRPC forwards RPC requests to a node in the network via a WebSocket
 // connection
 func (s *Server) NodeRPC(w http.ResponseWriter, req *http.Request) {
-	node := req.Context().Value("node").(*Node)
-
-	handler := func(conn *websocket.Conn) {
-		node.ServeRPC(conn)
+	conn, err := wsUpgrade.Upgrade(w, req, nil)
+	if err != nil {
+		return
 	}
-
-	websocket.Server{Handler: handler}.ServeHTTP(w, req)
+	defer conn.Close()
+	node := req.Context().Value("node").(*Node)
+	node.ServeRPC(conn)
 }
 
 // ServeHTTP implements the http.Handler interface by delegating to the