neko/internal/websocket/manager.go
2023-03-31 12:02:19 +02:00

416 lines
10 KiB
Go

package websocket
import (
"encoding/json"
"net/http"
"sync"
"time"
"github.com/gorilla/websocket"
"github.com/rs/zerolog"
"github.com/rs/zerolog/log"
"github.com/demodesk/neko/internal/websocket/handler"
"github.com/demodesk/neko/pkg/types"
"github.com/demodesk/neko/pkg/types/event"
"github.com/demodesk/neko/pkg/types/message"
"github.com/demodesk/neko/pkg/utils"
)
// send pings to peer with this period - must be less than pongWait
const pingPeriod = 10 * time.Second
// period for sending inactive cursor messages
const inactiveCursorsPeriod = 750 * time.Millisecond
// maximum payload length for logging
const maxPayloadLogLength = 10_000
// events that are not logged in debug mode
var nologEvents = []string{
// don't log twice
event.SYSTEM_LOGS,
// don't log heartbeat
event.SYSTEM_HEARTBEAT,
// don't log every cursor update
event.SESSION_CURSORS,
}
func New(
sessions types.SessionManager,
desktop types.DesktopManager,
capture types.CaptureManager,
webrtc types.WebRTCManager,
) *WebSocketManagerCtx {
logger := log.With().Str("module", "websocket").Logger()
return &WebSocketManagerCtx{
logger: logger,
shutdown: make(chan struct{}),
sessions: sessions,
desktop: desktop,
handler: handler.New(sessions, desktop, capture, webrtc),
handlers: []types.WebSocketHandler{},
}
}
type WebSocketManagerCtx struct {
logger zerolog.Logger
wg sync.WaitGroup
shutdown chan struct{}
sessions types.SessionManager
desktop types.DesktopManager
handler *handler.MessageHandlerCtx
handlers []types.WebSocketHandler
shutdownInactiveCursors chan struct{}
}
func (manager *WebSocketManagerCtx) Start() {
manager.sessions.OnCreated(func(session types.Session) {
err := manager.handler.SessionCreated(session)
manager.logger.Err(err).
Str("session_id", session.ID()).
Msg("session created")
})
manager.sessions.OnDeleted(func(session types.Session) {
err := manager.handler.SessionDeleted(session)
manager.logger.Err(err).
Str("session_id", session.ID()).
Msg("session deleted")
})
manager.sessions.OnConnected(func(session types.Session) {
err := manager.handler.SessionConnected(session)
manager.logger.Err(err).
Str("session_id", session.ID()).
Msg("session connected")
})
manager.sessions.OnDisconnected(func(session types.Session) {
err := manager.handler.SessionDisconnected(session)
manager.logger.Err(err).
Str("session_id", session.ID()).
Msg("session disconnected")
})
manager.sessions.OnProfileChanged(func(session types.Session) {
err := manager.handler.SessionProfileChanged(session)
manager.logger.Err(err).
Str("session_id", session.ID()).
Msg("session profile changed")
})
manager.sessions.OnStateChanged(func(session types.Session) {
err := manager.handler.SessionStateChanged(session)
manager.logger.Err(err).
Str("session_id", session.ID()).
Msg("session state changed")
})
manager.sessions.OnHostChanged(func(session types.Session) {
payload := message.ControlHost{
HasHost: session != nil,
}
if payload.HasHost {
payload.HostID = session.ID()
}
manager.sessions.Broadcast(event.CONTROL_HOST, payload)
manager.logger.Info().
Bool("has_host", payload.HasHost).
Str("host_id", payload.HostID).
Msg("session host changed")
})
manager.sessions.OnSettingsChanged(func(new types.Settings, old types.Settings) {
// start inactive cursors
if new.InactiveCursors && !old.InactiveCursors {
manager.startInactiveCursors()
}
// stop inactive cursors
if !new.InactiveCursors && old.InactiveCursors {
manager.stopInactiveCursors()
}
manager.sessions.Broadcast(event.SYSTEM_SETTINGS, new)
manager.logger.Info().
Interface("new", new).
Interface("old", old).
Msg("settings changed")
})
manager.desktop.OnClipboardUpdated(func() {
host, hasHost := manager.sessions.GetHost()
if !hasHost || !host.Profile().CanAccessClipboard {
return
}
manager.logger.Info().Msg("sync clipboard")
data, err := manager.desktop.ClipboardGetText()
if err != nil {
manager.logger.Err(err).Msg("could not get clipboard content")
return
}
host.Send(
event.CLIPBOARD_UPDATED,
message.ClipboardData{
Text: data.Text,
// TODO: Send HTML?
})
})
manager.fileChooserDialogEvents()
if manager.sessions.Settings().InactiveCursors {
manager.startInactiveCursors()
}
manager.logger.Info().Msg("websocket starting")
}
func (manager *WebSocketManagerCtx) Shutdown() error {
manager.logger.Info().Msg("shutdown")
close(manager.shutdown)
manager.stopInactiveCursors()
manager.wg.Wait()
return nil
}
func (manager *WebSocketManagerCtx) AddHandler(handler types.WebSocketHandler) {
manager.handlers = append(manager.handlers, handler)
}
func (manager *WebSocketManagerCtx) Upgrade(checkOrigin types.CheckOrigin) types.RouterHandler {
return func(w http.ResponseWriter, r *http.Request) error {
upgrader := websocket.Upgrader{
CheckOrigin: checkOrigin,
// Do not return any error while handshake
Error: func(w http.ResponseWriter, r *http.Request, status int, reason error) {},
}
connection, err := upgrader.Upgrade(w, r, nil)
if err != nil {
return utils.HttpBadRequest().WithInternalErr(err)
}
// Cannot write HTTP response after connection upgrade
manager.connect(connection, r)
return nil
}
}
func (manager *WebSocketManagerCtx) connect(connection *websocket.Conn, r *http.Request) {
// create new peer
peer := newPeer(connection)
session, err := manager.sessions.Authenticate(r)
if err != nil {
manager.logger.Warn().Err(err).Msg("authentication failed")
peer.Destroy(err.Error())
return
}
// add session id to all log messages
logger := manager.logger.With().Str("session_id", session.ID()).Logger()
peer.setSessionID(session.ID())
if !session.Profile().CanConnect {
logger.Warn().Msg("connection disabled")
peer.Destroy("connection disabled")
return
}
if session.State().IsConnected {
logger.Warn().Msg("already connected")
if !manager.sessions.Settings().MercifulReconnect {
peer.Destroy("already connected")
return
}
logger.Info().Msg("replacing peer connection")
}
session.SetWebSocketPeer(peer)
logger.Info().
Str("address", connection.RemoteAddr().String()).
Str("agent", r.UserAgent()).
Msg("connection started")
session.SetWebSocketConnected(peer, true, false)
// this is a blocking function that lives
// throughout whole websocket connection
err = manager.handle(connection, peer, session)
logger.Info().
Str("address", connection.RemoteAddr().String()).
Str("agent", r.UserAgent()).
Msg("connection ended")
delayedDisconnect := false
e, ok := err.(*websocket.CloseError)
if !ok {
logger.Err(err).Msg("read message error")
// client is expected to reconnect soon
delayedDisconnect = true
} else {
switch e.Code {
case websocket.CloseNormalClosure:
logger.Info().Str("reason", e.Text).Msg("websocket close")
case websocket.CloseGoingAway:
logger.Info().Str("reason", "going away").Msg("websocket close")
default:
logger.Warn().Err(err).Msg("websocket close")
// abnormal websocket closure:
// client is expected to reconnect soon
delayedDisconnect = true
}
}
session.SetWebSocketConnected(peer, false, delayedDisconnect)
}
func (manager *WebSocketManagerCtx) handle(connection *websocket.Conn, peer types.WebSocketPeer, session types.Session) error {
// add session id to logger context
logger := manager.logger.With().Str("session_id", session.ID()).Logger()
bytes := make(chan []byte)
cancel := make(chan error)
ticker := time.NewTicker(pingPeriod)
defer ticker.Stop()
manager.wg.Add(1)
go func() {
defer manager.wg.Done()
for {
_, raw, err := connection.ReadMessage()
if err != nil {
cancel <- err
break
}
bytes <- raw
}
}()
for {
select {
case raw := <-bytes:
data := types.WebSocketMessage{}
if err := json.Unmarshal(raw, &data); err != nil {
logger.Err(err).Msg("message unmarshalling has failed")
break
}
// log events if not ignored
if ok, _ := utils.ArrayIn(data.Event, nologEvents); !ok {
payload := data.Payload
if len(payload) > maxPayloadLogLength {
payload = []byte("<truncated>")
}
logger.Debug().
Str("address", connection.RemoteAddr().String()).
Str("event", data.Event).
Str("payload", string(payload)).
Msg("received message from client")
}
handled := manager.handler.Message(session, data)
for _, handler := range manager.handlers {
if handled {
break
}
handled = handler(session, data)
}
if !handled {
logger.Warn().Str("event", data.Event).Msg("unhandled message")
}
case err := <-cancel:
return err
case <-manager.shutdown:
peer.Destroy("connection shutdown")
return nil
case <-ticker.C:
if err := peer.Ping(); err != nil {
return err
}
}
}
}
func (manager *WebSocketManagerCtx) startInactiveCursors() {
if manager.shutdownInactiveCursors != nil {
manager.logger.Warn().Msg("inactive cursors handler already running")
return
}
manager.logger.Info().Msg("starting inactive cursors handler")
manager.shutdownInactiveCursors = make(chan struct{})
manager.wg.Add(1)
go func() {
defer manager.wg.Done()
ticker := time.NewTicker(inactiveCursorsPeriod)
defer ticker.Stop()
var currentEmpty bool
var lastEmpty = false
for {
select {
case <-manager.shutdownInactiveCursors:
manager.logger.Info().Msg("stopping inactive cursors handler")
manager.shutdownInactiveCursors = nil
// remove last cursor entries and send empty message
_ = manager.sessions.PopCursors()
manager.sessions.InactiveCursorsBroadcast(event.SESSION_CURSORS, []message.SessionCursors{})
return
case <-ticker.C:
cursorsMap := manager.sessions.PopCursors()
currentEmpty = len(cursorsMap) == 0
if currentEmpty && lastEmpty {
continue
}
lastEmpty = currentEmpty
sessionCursors := []message.SessionCursors{}
for session, cursors := range cursorsMap {
sessionCursors = append(
sessionCursors,
message.SessionCursors{
ID: session.ID(),
Cursors: cursors,
},
)
}
manager.sessions.InactiveCursorsBroadcast(event.SESSION_CURSORS, sessionCursors)
}
}
}()
}
func (manager *WebSocketManagerCtx) stopInactiveCursors() {
if manager.shutdownInactiveCursors != nil {
close(manager.shutdownInactiveCursors)
}
}