package server
|
|
|
|
import (
|
|
"context"
|
|
"encoding/json"
|
|
"fmt"
|
|
"net/http"
|
|
"reflect"
|
|
"runtime/debug"
|
|
"time"
|
|
|
|
"github.com/gorilla/websocket"
|
|
|
|
"github.com/tendermint/tendermint/libs/log"
|
|
"github.com/tendermint/tendermint/libs/service"
|
|
types "github.com/tendermint/tendermint/rpc/jsonrpc/types"
|
|
)
|
|
|
|
///////////////////////////////////////////////////////////////////////////////
|
|
// WebSocket handler
|
|
///////////////////////////////////////////////////////////////////////////////
|
|
|
|
const (
|
|
defaultWSWriteChanCapacity = 1000
|
|
defaultWSWriteWait = 10 * time.Second
|
|
defaultWSReadWait = 30 * time.Second
|
|
defaultWSPingPeriod = (defaultWSReadWait * 9) / 10
|
|
)
|
|
|
|
// WebsocketManager provides a WS handler for incoming connections and passes a
|
|
// map of functions along with any additional params to new connections.
|
|
// NOTE: The websocket path is defined externally, e.g. in node/node.go
|
|
type WebsocketManager struct {
|
|
websocket.Upgrader
|
|
|
|
funcMap map[string]*RPCFunc
|
|
logger log.Logger
|
|
wsConnOptions []func(*wsConnection)
|
|
}
|
|
|
|
// NewWebsocketManager returns a new WebsocketManager that passes a map of
|
|
// functions, connection options and logger to new WS connections.
|
|
func NewWebsocketManager(
|
|
funcMap map[string]*RPCFunc,
|
|
wsConnOptions ...func(*wsConnection),
|
|
) *WebsocketManager {
|
|
return &WebsocketManager{
|
|
funcMap: funcMap,
|
|
Upgrader: websocket.Upgrader{
|
|
CheckOrigin: func(r *http.Request) bool {
|
|
// TODO ???
|
|
//
|
|
// The default behaviour would be relevant to browser-based clients,
|
|
// afaik. I suppose having a pass-through is a workaround for allowing
|
|
// for more complex security schemes, shifting the burden of
|
|
// AuthN/AuthZ outside the Tendermint RPC.
|
|
// I can't think of other uses right now that would warrant a TODO
|
|
// though. The real backstory of this TODO shall remain shrouded in
|
|
// mystery
|
|
return true
|
|
},
|
|
},
|
|
logger: log.NewNopLogger(),
|
|
wsConnOptions: wsConnOptions,
|
|
}
|
|
}
|
|
|
|
// SetLogger sets the logger.
|
|
func (wm *WebsocketManager) SetLogger(l log.Logger) {
|
|
wm.logger = l
|
|
}
|
|
|
|
// WebsocketHandler upgrades the request/response (via http.Hijack) and starts
|
|
// the wsConnection.
|
|
func (wm *WebsocketManager) WebsocketHandler(w http.ResponseWriter, r *http.Request) {
|
|
wsConn, err := wm.Upgrade(w, r, nil)
|
|
if err != nil {
|
|
// TODO - return http error
|
|
wm.logger.Error("Failed to upgrade connection", "err", err)
|
|
return
|
|
}
|
|
defer func() {
|
|
if err := wsConn.Close(); err != nil {
|
|
wm.logger.Error("Failed to close connection", "err", err)
|
|
}
|
|
}()
|
|
|
|
// register connection
|
|
con := newWSConnection(wsConn, wm.funcMap, wm.wsConnOptions...)
|
|
con.SetLogger(wm.logger.With("remote", wsConn.RemoteAddr()))
|
|
wm.logger.Info("New websocket connection", "remote", con.remoteAddr)
|
|
err = con.Start() // BLOCKING
|
|
if err != nil {
|
|
wm.logger.Error("Failed to start connection", "err", err)
|
|
return
|
|
}
|
|
con.Stop()
|
|
}
|
|
|
|
///////////////////////////////////////////////////////////////////////////////
|
|
// WebSocket connection
|
|
///////////////////////////////////////////////////////////////////////////////
|
|
|
|
// A single websocket connection contains listener id, underlying ws
|
|
// connection, and the event switch for subscribing to events.
|
|
//
|
|
// In case of an error, the connection is stopped.
|
|
type wsConnection struct {
|
|
service.BaseService
|
|
|
|
remoteAddr string
|
|
baseConn *websocket.Conn
|
|
// writeChan is never closed, to allow WriteRPCResponse() to fail.
|
|
writeChan chan types.RPCResponse
|
|
|
|
// chan, which is closed when/if readRoutine errors
|
|
// used to abort writeRoutine
|
|
readRoutineQuit chan struct{}
|
|
|
|
funcMap map[string]*RPCFunc
|
|
|
|
// write channel capacity
|
|
writeChanCapacity int
|
|
|
|
// each write times out after this.
|
|
writeWait time.Duration
|
|
|
|
// Connection times out if we haven't received *anything* in this long, not even pings.
|
|
readWait time.Duration
|
|
|
|
// Send pings to server with this period. Must be less than readWait, but greater than zero.
|
|
pingPeriod time.Duration
|
|
|
|
// Maximum message size.
|
|
readLimit int64
|
|
|
|
// callback which is called upon disconnect
|
|
onDisconnect func(remoteAddr string)
|
|
|
|
ctx context.Context
|
|
cancel context.CancelFunc
|
|
}
|
|
|
|
// NewWSConnection wraps websocket.Conn.
|
|
//
|
|
// See the commentary on the func(*wsConnection) functions for a detailed
|
|
// description of how to configure ping period and pong wait time. NOTE: if the
|
|
// write buffer is full, pongs may be dropped, which may cause clients to
|
|
// disconnect. see https://github.com/gorilla/websocket/issues/97
|
|
func newWSConnection(
|
|
baseConn *websocket.Conn,
|
|
funcMap map[string]*RPCFunc,
|
|
options ...func(*wsConnection),
|
|
) *wsConnection {
|
|
wsc := &wsConnection{
|
|
remoteAddr: baseConn.RemoteAddr().String(),
|
|
baseConn: baseConn,
|
|
funcMap: funcMap,
|
|
writeWait: defaultWSWriteWait,
|
|
writeChanCapacity: defaultWSWriteChanCapacity,
|
|
readWait: defaultWSReadWait,
|
|
pingPeriod: defaultWSPingPeriod,
|
|
readRoutineQuit: make(chan struct{}),
|
|
}
|
|
for _, option := range options {
|
|
option(wsc)
|
|
}
|
|
wsc.baseConn.SetReadLimit(wsc.readLimit)
|
|
wsc.BaseService = *service.NewBaseService(nil, "wsConnection", wsc)
|
|
return wsc
|
|
}
|
|
|
|
// OnDisconnect sets a callback which is used upon disconnect - not
|
|
// Goroutine-safe. Nop by default.
|
|
func OnDisconnect(onDisconnect func(remoteAddr string)) func(*wsConnection) {
|
|
return func(wsc *wsConnection) {
|
|
wsc.onDisconnect = onDisconnect
|
|
}
|
|
}
|
|
|
|
// WriteWait sets the amount of time to wait before a websocket write times out.
|
|
// It should only be used in the constructor - not Goroutine-safe.
|
|
func WriteWait(writeWait time.Duration) func(*wsConnection) {
|
|
return func(wsc *wsConnection) {
|
|
wsc.writeWait = writeWait
|
|
}
|
|
}
|
|
|
|
// WriteChanCapacity sets the capacity of the websocket write channel.
|
|
// It should only be used in the constructor - not Goroutine-safe.
|
|
func WriteChanCapacity(cap int) func(*wsConnection) {
|
|
return func(wsc *wsConnection) {
|
|
wsc.writeChanCapacity = cap
|
|
}
|
|
}
|
|
|
|
// ReadWait sets the amount of time to wait before a websocket read times out.
|
|
// It should only be used in the constructor - not Goroutine-safe.
|
|
func ReadWait(readWait time.Duration) func(*wsConnection) {
|
|
return func(wsc *wsConnection) {
|
|
wsc.readWait = readWait
|
|
}
|
|
}
|
|
|
|
// PingPeriod sets the duration for sending websocket pings.
|
|
// It should only be used in the constructor - not Goroutine-safe.
|
|
func PingPeriod(pingPeriod time.Duration) func(*wsConnection) {
|
|
return func(wsc *wsConnection) {
|
|
wsc.pingPeriod = pingPeriod
|
|
}
|
|
}
|
|
|
|
// ReadLimit sets the maximum size for reading message.
|
|
// It should only be used in the constructor - not Goroutine-safe.
|
|
func ReadLimit(readLimit int64) func(*wsConnection) {
|
|
return func(wsc *wsConnection) {
|
|
wsc.readLimit = readLimit
|
|
}
|
|
}
|
|
|
|
// OnStart implements service.Service by starting the read and write routines. It
|
|
// blocks until there's some error.
|
|
func (wsc *wsConnection) OnStart() error {
|
|
wsc.writeChan = make(chan types.RPCResponse, wsc.writeChanCapacity)
|
|
|
|
// Read subscriptions/unsubscriptions to events
|
|
go wsc.readRoutine()
|
|
// Write responses, BLOCKING.
|
|
wsc.writeRoutine()
|
|
|
|
return nil
|
|
}
|
|
|
|
// OnStop implements service.Service by unsubscribing remoteAddr from all
|
|
// subscriptions.
|
|
func (wsc *wsConnection) OnStop() {
|
|
if wsc.onDisconnect != nil {
|
|
wsc.onDisconnect(wsc.remoteAddr)
|
|
}
|
|
|
|
if wsc.ctx != nil {
|
|
wsc.cancel()
|
|
}
|
|
}
|
|
|
|
// GetRemoteAddr returns the remote address of the underlying connection.
|
|
// It implements WSRPCConnection
|
|
func (wsc *wsConnection) GetRemoteAddr() string {
|
|
return wsc.remoteAddr
|
|
}
|
|
|
|
// WriteRPCResponse pushes a response to the writeChan, and blocks until it is accepted.
|
|
// It implements WSRPCConnection. It is Goroutine-safe.
|
|
func (wsc *wsConnection) WriteRPCResponse(resp types.RPCResponse) {
|
|
select {
|
|
case <-wsc.Quit():
|
|
return
|
|
case wsc.writeChan <- resp:
|
|
}
|
|
}
|
|
|
|
// TryWriteRPCResponse attempts to push a response to the writeChan, but does not block.
|
|
// It implements WSRPCConnection. It is Goroutine-safe
|
|
func (wsc *wsConnection) TryWriteRPCResponse(resp types.RPCResponse) bool {
|
|
select {
|
|
case <-wsc.Quit():
|
|
return false
|
|
case wsc.writeChan <- resp:
|
|
return true
|
|
default:
|
|
return false
|
|
}
|
|
}
|
|
|
|
// Context returns the connection's context.
|
|
// The context is canceled when the client's connection closes.
|
|
func (wsc *wsConnection) Context() context.Context {
|
|
if wsc.ctx != nil {
|
|
return wsc.ctx
|
|
}
|
|
wsc.ctx, wsc.cancel = context.WithCancel(context.Background())
|
|
return wsc.ctx
|
|
}
|
|
|
|
// Read from the socket and subscribe to or unsubscribe from events
|
|
func (wsc *wsConnection) readRoutine() {
|
|
defer func() {
|
|
if r := recover(); r != nil {
|
|
err, ok := r.(error)
|
|
if !ok {
|
|
err = fmt.Errorf("WSJSONRPC: %v", r)
|
|
}
|
|
wsc.Logger.Error("Panic in WSJSONRPC handler", "err", err, "stack", string(debug.Stack()))
|
|
wsc.WriteRPCResponse(types.RPCInternalError(types.JSONRPCIntID(-1), err))
|
|
go wsc.readRoutine()
|
|
}
|
|
}()
|
|
|
|
wsc.baseConn.SetPongHandler(func(m string) error {
|
|
return wsc.baseConn.SetReadDeadline(time.Now().Add(wsc.readWait))
|
|
})
|
|
|
|
for {
|
|
select {
|
|
case <-wsc.Quit():
|
|
return
|
|
default:
|
|
// reset deadline for every type of message (control or data)
|
|
if err := wsc.baseConn.SetReadDeadline(time.Now().Add(wsc.readWait)); err != nil {
|
|
wsc.Logger.Error("failed to set read deadline", "err", err)
|
|
}
|
|
var in []byte
|
|
_, in, err := wsc.baseConn.ReadMessage()
|
|
if err != nil {
|
|
if websocket.IsCloseError(err, websocket.CloseNormalClosure) {
|
|
wsc.Logger.Info("Client closed the connection")
|
|
} else {
|
|
wsc.Logger.Error("Failed to read request", "err", err)
|
|
}
|
|
wsc.Stop()
|
|
close(wsc.readRoutineQuit)
|
|
return
|
|
}
|
|
|
|
var request types.RPCRequest
|
|
err = json.Unmarshal(in, &request)
|
|
if err != nil {
|
|
wsc.WriteRPCResponse(types.RPCParseError(fmt.Errorf("error unmarshaling request: %w", err)))
|
|
continue
|
|
}
|
|
|
|
// A Notification is a Request object without an "id" member.
|
|
// The Server MUST NOT reply to a Notification, including those that are within a batch request.
|
|
if request.ID == nil {
|
|
wsc.Logger.Debug(
|
|
"WSJSONRPC received a notification, skipping... (please send a non-empty ID if you want to call a method)",
|
|
"req", request,
|
|
)
|
|
continue
|
|
}
|
|
|
|
// Now, fetch the RPCFunc and execute it.
|
|
rpcFunc := wsc.funcMap[request.Method]
|
|
if rpcFunc == nil {
|
|
wsc.WriteRPCResponse(types.RPCMethodNotFoundError(request.ID))
|
|
continue
|
|
}
|
|
|
|
ctx := &types.Context{JSONReq: &request, WSConn: wsc}
|
|
args := []reflect.Value{reflect.ValueOf(ctx)}
|
|
if len(request.Params) > 0 {
|
|
fnArgs, err := jsonParamsToArgs(rpcFunc, request.Params)
|
|
if err != nil {
|
|
wsc.WriteRPCResponse(
|
|
types.RPCInternalError(request.ID, fmt.Errorf("error converting json params to arguments: %w", err)),
|
|
)
|
|
continue
|
|
}
|
|
args = append(args, fnArgs...)
|
|
}
|
|
|
|
returns := rpcFunc.f.Call(args)
|
|
|
|
// TODO: Need to encode args/returns to string if we want to log them
|
|
wsc.Logger.Info("WSJSONRPC", "method", request.Method)
|
|
|
|
result, err := unreflectResult(returns)
|
|
if err != nil {
|
|
wsc.WriteRPCResponse(types.RPCInternalError(request.ID, err))
|
|
continue
|
|
}
|
|
|
|
wsc.WriteRPCResponse(types.NewRPCSuccessResponse(request.ID, result))
|
|
}
|
|
}
|
|
}
|
|
|
|
// receives on a write channel and writes out on the socket
|
|
func (wsc *wsConnection) writeRoutine() {
|
|
pingTicker := time.NewTicker(wsc.pingPeriod)
|
|
defer func() {
|
|
pingTicker.Stop()
|
|
}()
|
|
|
|
// https://github.com/gorilla/websocket/issues/97
|
|
pongs := make(chan string, 1)
|
|
wsc.baseConn.SetPingHandler(func(m string) error {
|
|
select {
|
|
case pongs <- m:
|
|
default:
|
|
}
|
|
return nil
|
|
})
|
|
|
|
for {
|
|
select {
|
|
case <-wsc.Quit():
|
|
return
|
|
case <-wsc.readRoutineQuit: // error in readRoutine
|
|
return
|
|
case m := <-pongs:
|
|
err := wsc.writeMessageWithDeadline(websocket.PongMessage, []byte(m))
|
|
if err != nil {
|
|
wsc.Logger.Info("Failed to write pong (client may disconnect)", "err", err)
|
|
}
|
|
case <-pingTicker.C:
|
|
err := wsc.writeMessageWithDeadline(websocket.PingMessage, []byte{})
|
|
if err != nil {
|
|
wsc.Logger.Error("Failed to write ping", "err", err)
|
|
return
|
|
}
|
|
case msg := <-wsc.writeChan:
|
|
jsonBytes, err := json.MarshalIndent(msg, "", " ")
|
|
if err != nil {
|
|
wsc.Logger.Error("Failed to marshal RPCResponse to JSON", "err", err)
|
|
} else if err = wsc.writeMessageWithDeadline(websocket.TextMessage, jsonBytes); err != nil {
|
|
wsc.Logger.Error("Failed to write response", "msg", msg, "err", err)
|
|
return
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
// All writes to the websocket must (re)set the write deadline.
|
|
// If some writes don't set it while others do, they may timeout incorrectly
|
|
// (https://github.com/tendermint/tendermint/issues/553)
|
|
func (wsc *wsConnection) writeMessageWithDeadline(msgType int, msg []byte) error {
|
|
if err := wsc.baseConn.SetWriteDeadline(time.Now().Add(wsc.writeWait)); err != nil {
|
|
return err
|
|
}
|
|
return wsc.baseConn.WriteMessage(msgType, msg)
|
|
}
|