package common import ( "encoding/json" "log" "sync" "time" "github.com/gorilla/websocket" ) // TODO: Rename this to WebSockets? var WsHub WsHubImpl // TODO: Make this an interface? // TODO: Write tests for this type WsHubImpl struct { // TODO: Implement some form of generics so we don't write as much odd-even sharding code evenOnlineUsers map[int]*WSUser oddOnlineUsers map[int]*WSUser evenUserLock sync.RWMutex oddUserLock sync.RWMutex // TODO: Add sharding for this too? OnlineGuests map[*WSUser]bool GuestLock sync.RWMutex lastTick time.Time lastTopicList []*TopicsRow } func init() { // TODO: Do we really want to initialise this here instead of in main.go / general_test.go like the other things? WsHub = WsHubImpl{ evenOnlineUsers: make(map[int]*WSUser), oddOnlineUsers: make(map[int]*WSUser), OnlineGuests: make(map[*WSUser]bool), } } func (h *WsHubImpl) Start() { log.Print("Setting up the WebSocket ticks") ticker := time.NewTicker(time.Minute * 5) defer func() { ticker.Stop() }() go func() { for { item := func(l *sync.RWMutex, userMap map[int]*WSUser) { l.RLock() defer l.RUnlock() // TODO: Copy to temporary slice for less contention? for _, u := range userMap { u.Ping() } } select { case <-ticker.C: item(&h.evenUserLock, h.evenOnlineUsers) item(&h.oddUserLock, h.oddOnlineUsers) } } }() if Config.DisableLiveTopicList { return } h.lastTick = time.Now() AddScheduledSecondTask(h.Tick) } // This Tick is separate from the admin one, as we want to process that in parallel with this due to the blocking calls to gopsutil func (h *WsHubImpl) Tick() error { return wsTopicListTick(h) } func wsTopicListTick(h *WsHubImpl) error { // Avoid hitting GetList when the topic list hasn't changed if !TopicListThaw.Thawed() && h.lastTopicList != nil { return nil } tickStart := time.Now() // Don't waste CPU time if nothing has happened // TODO: Get a topic list method which strips stickies? tList, _, _, err := TopicList.GetList(1, 0, nil) if err != nil { h.lastTick = tickStart return err // TODO: Do we get ErrNoRows here? } defer func() { h.lastTick = tickStart h.lastTopicList = tList }() if len(tList) == 0 { return nil } // TODO: Optimise this by only sniffing the top non-sticky // TODO: Optimise this by getting back an unsorted list so we don't have to hop around the stickies // TODO: Add support for new stickies / replies to them if len(tList) == len(h.lastTopicList) { hasItem := false for j, tItem := range tList { if !tItem.Sticky { if tItem.ID != h.lastTopicList[j].ID || !tItem.LastReplyAt.Equal(h.lastTopicList[j].LastReplyAt) { hasItem = true break } } } if !hasItem { return nil } } // TODO: Implement this for guests too? Should be able to optimise it far better there due to them sharing the same permission set // TODO: Be less aggressive with the locking, maybe use an array of sorts instead of hitting the main map every-time topicListMutex.RLock() if len(topicListWatchers) == 0 { topicListMutex.RUnlock() return nil } // Copy these over so we close this loop as fast as possible so we can release the read lock, especially if the group gets are backed by calls to the database groupIDs := make(map[int]bool) currentWatchers := make([]*WSUser, len(topicListWatchers)) i := 0 for wsUser, _ := range topicListWatchers { currentWatchers[i] = wsUser groupIDs[wsUser.User.Group] = true i++ } topicListMutex.RUnlock() groups := make(map[int]*Group) canSeeMap := make(map[string][]int) for gid, _ := range groupIDs { g, err := Groups.Get(gid) if err != nil { // TODO: Do we really want to halt all pushes for what is possibly just one user? return err } groups[g.ID] = g canSee := make([]byte, len(g.CanSee)) for i, item := range g.CanSee { canSee[i] = byte(item) } canSeeMap[string(canSee)] = g.CanSee } canSeeRenders := make(map[string][]byte) canSeeLists := make(map[string][]*WsTopicsRow) for name, canSee := range canSeeMap { topicList, forumList, _, err := TopicList.GetListByCanSee(canSee, 1, 0, nil) if err != nil { return err // TODO: Do we get ErrNoRows here? } if len(topicList) == 0 { continue } _ = forumList // Might use this later after we get the base feature working if topicList[0].Sticky { lastSticky := 0 for i, row := range topicList { if !row.Sticky { lastSticky = i break } } if lastSticky == 0 { continue } topicList = topicList[lastSticky:] } // TODO: Compare to previous tick to eliminate unnecessary work and data wsTopicList := make([]*WsTopicsRow, len(topicList)) for i, topicRow := range topicList { wsTopicList[i] = topicRow.WebSockets() } canSeeLists[name] = wsTopicList outBytes, err := json.Marshal(&WsTopicList{wsTopicList, 0, tickStart.Unix()}) if err != nil { return err } canSeeRenders[name] = outBytes } // TODO: Use MessagePack for additional speed? //fmt.Println("writing to the clients") for _, wsUser := range currentWatchers { u := wsUser.User group := groups[u.Group] canSee := make([]byte, len(group.CanSee)) for i, item := range group.CanSee { canSee[i] = byte(item) } sCanSee := string(canSee) l := canSeeLists[sCanSee] // TODO: Optimise this away for guests? anyMod, anyLock, anyMove, allMod := false, false, false, true var modSet map[int]int if u.IsSuperAdmin { anyMod = true anyLock = true anyMove = true } else { modSet = make(map[int]int, len(l)) for i, t := range l { // TODO: Abstract this? fp, e := FPStore.Get(t.ParentID, u.Group) if e == ErrNoRows { fp = BlankForumPerms() } else if e != nil { return e } var ccanMod, ccanLock, ccanMove bool if fp.Overrides { ccanLock = fp.CloseTopic ccanMove = fp.MoveTopic ccanMod = t.CreatedBy == u.ID || fp.DeleteTopic || ccanLock || ccanMove } else { ccanLock = u.Perms.CloseTopic ccanMove = u.Perms.MoveTopic ccanMod = t.CreatedBy == u.ID || u.Perms.DeleteTopic || ccanLock || ccanMove } if ccanLock { anyLock = true } if ccanMove { anyMove = true } if ccanMod { anyMod = true } else { allMod = false } var v int if ccanMod { v = 1 } modSet[i] = v } } //fmt.Println("writing to user #", wsUser.User.ID) outBytes := canSeeRenders[sCanSee] //fmt.Println("outBytes: ", string(outBytes)) //fmt.Println("outBytes[:len(outBytes)-1]: ", string(outBytes[:len(outBytes)-1])) //e := wsUser.WriteToPageBytes(outBytes, "/topics/") //e := wsUser.WriteToPageBytesMulti([][]byte{outBytes[:len(outBytes)-1], []byte(`,"mod":1}`)}, "/topics/") var e error if !anyMod { e = wsUser.WriteToPageBytes(outBytes, "/topics/") } else { var lm []byte if anyLock && anyMove { lm = []byte(`,"lock":1,"move":1}`) } else if anyLock { lm = []byte(`,"lock":1}`) } else if anyMove { lm = []byte(`,"move":1}`) } else { lm = []byte("}") } if allMod { e = wsUser.WriteToPageBytesMulti([][]byte{outBytes[:len(outBytes)-1], []byte(`,"mod":1`), lm}, "/topics/") } else { // TODO: Temporary and inefficient mBytes, err := json.Marshal(modSet) if err != nil { return err } e = wsUser.WriteToPageBytesMulti([][]byte{outBytes[:len(outBytes)-1], []byte(`,"mod":`), mBytes, lm}, "/topics/") } } if e == ErrNoneOnPage { //fmt.Printf("werr for #%d: %s\n", wsUser.User.ID, err) wsUser.FinalizePage("/topics/", func() { topicListMutex.Lock() delete(topicListWatchers, wsUser) topicListMutex.Unlock() }) continue } } return nil } func (h *WsHubImpl) GuestCount() int { h.GuestLock.RLock() defer h.GuestLock.RUnlock() return len(h.OnlineGuests) } func (h *WsHubImpl) UserCount() (count int) { h.evenUserLock.RLock() count += len(h.evenOnlineUsers) h.evenUserLock.RUnlock() h.oddUserLock.RLock() count += len(h.oddOnlineUsers) h.oddUserLock.RUnlock() return count } func (h *WsHubImpl) HasUser(uid int) (exists bool) { h.evenUserLock.RLock() _, exists = h.evenOnlineUsers[uid] h.evenUserLock.RUnlock() if exists { return exists } h.oddUserLock.RLock() _, exists = h.oddOnlineUsers[uid] h.oddUserLock.RUnlock() return exists } func (h *WsHubImpl) broadcastMessage(msg string) error { userLoop := func(users map[int]*WSUser, m *sync.RWMutex) error { m.RLock() defer m.RUnlock() for _, wsUser := range users { e := wsUser.WriteAll(msg) if e != nil { return e } } return nil } // TODO: Can we move this RLock inside the closure safely? e := userLoop(h.evenOnlineUsers, &h.evenUserLock) if e != nil { return e } return userLoop(h.oddOnlineUsers, &h.oddUserLock) } func (h *WsHubImpl) getUser(uid int) (wsUser *WSUser, err error) { var ok bool if uid%2 == 0 { h.evenUserLock.RLock() wsUser, ok = h.evenOnlineUsers[uid] h.evenUserLock.RUnlock() } else { h.oddUserLock.RLock() wsUser, ok = h.oddOnlineUsers[uid] h.oddUserLock.RUnlock() } if !ok { return nil, errWsNouser } return wsUser, nil } // Warning: For efficiency, some of the *WSUsers may be nil pointers, DO NOT EXPORT func (h *WsHubImpl) getUsers(uids []int) (wsUsers []*WSUser, err error) { if len(uids) == 0 { return nil, errWsNouser } wsUsers = make([]*WSUser, len(uids)) i := 0 appender := func(l *sync.RWMutex, users map[int]*WSUser) { l.RLock() defer l.RUnlock() // We don't want to keep a lock on this for too long, so we'll accept some nil pointers for _, uid := range uids { wsUsers[i] = users[uid] i++ } } appender(&h.evenUserLock, h.evenOnlineUsers) appender(&h.oddUserLock, h.oddOnlineUsers) if len(wsUsers) == 0 { return nil, errWsNouser } return wsUsers, nil } // For Widget WOL, please avoid using this as it might wind up being really long and slow without the right safeguards func (h *WsHubImpl) AllUsers() (users []*User) { appender := func(l *sync.RWMutex, userMap map[int]*WSUser) { l.RLock() defer l.RUnlock() for _, u := range userMap { users = append(users, u.User) } } appender(&h.evenUserLock, h.evenOnlineUsers) appender(&h.oddUserLock, h.oddOnlineUsers) return users } func (h *WsHubImpl) removeUser(uid int) { if uid%2 == 0 { h.evenUserLock.Lock() delete(h.evenOnlineUsers, uid) h.evenUserLock.Unlock() } else { h.oddUserLock.Lock() delete(h.oddOnlineUsers, uid) h.oddUserLock.Unlock() } } func (h *WsHubImpl) AddConn(user *User, conn *websocket.Conn) (*WSUser, error) { if user.ID == 0 { wsUser := new(WSUser) wsUser.User = new(User) *wsUser.User = *user wsUser.AddSocket(conn, "") WsHub.GuestLock.Lock() WsHub.OnlineGuests[wsUser] = true WsHub.GuestLock.Unlock() return wsUser, nil } // TODO: How should we handle user state changes if we're holding a pointer which never changes? userptr, err := Users.Get(user.ID) if err != nil && err != ErrStoreCapacityOverflow { return nil, err } var mutex *sync.RWMutex var theMap map[int]*WSUser if user.ID%2 == 0 { mutex = &h.evenUserLock theMap = h.evenOnlineUsers } else { mutex = &h.oddUserLock theMap = h.oddOnlineUsers } mutex.Lock() wsUser, ok := theMap[user.ID] if !ok { wsUser = new(WSUser) wsUser.User = userptr wsUser.Sockets = []*WSUserSocket{{conn, ""}} theMap[user.ID] = wsUser mutex.Unlock() return wsUser, nil } mutex.Unlock() wsUser.AddSocket(conn, "") return wsUser, nil } func (h *WsHubImpl) RemoveConn(wsUser *WSUser, conn *websocket.Conn) { wsUser.RemoveSocket(conn) wsUser.Lock() if len(wsUser.Sockets) == 0 { h.removeUser(wsUser.User.ID) } wsUser.Unlock() } func (h *WsHubImpl) PushMessage(targetUser int, msg string) error { wsUser, e := h.getUser(targetUser) if e != nil { return e } return wsUser.WriteAll(msg) } func (h *WsHubImpl) pushAlert(targetUser int, a Alert) error { wsUser, e := h.getUser(targetUser) if e != nil { return e } astr, e := BuildAlert(a, *wsUser.User) if e != nil { return e } return wsUser.WriteAll(astr) } func (h *WsHubImpl) pushAlerts(users []int, a Alert) error { wsUsers, err := h.getUsers(users) if err != nil { return err } var errs []error for _, wsUser := range wsUsers { if wsUser == nil { continue } alert, err := BuildAlert(a, *wsUser.User) if err != nil { errs = append(errs, err) } err = wsUser.WriteAll(alert) if err != nil { errs = append(errs, err) } } // Return the first error if len(errs) != 0 { for _, e := range errs { return e } } return nil }