maubot/matrix/sync.go
2018-06-20 22:25:33 +03:00

153 lines
4.6 KiB
Go

package matrix
import (
"encoding/json"
"fmt"
"runtime/debug"
"time"
"maubot.xyz"
"maunium.net/go/gomatrix"
)
type MaubotSyncer struct {
Client *Client
Store gomatrix.Storer
listeners map[maubot.EventType][]maubot.EventHandler
}
// NewDefaultSyncer returns an instantiated DefaultSyncer
func NewMaubotSyncer(client *Client, store gomatrix.Storer) *MaubotSyncer {
return &MaubotSyncer{
Client: client,
Store: store,
listeners: make(map[maubot.EventType][]maubot.EventHandler),
}
}
// ProcessResponse processes the /sync response in a way suitable for bots. "Suitable for bots" means a stream of
// unrepeating events. Returns a fatal error if a listener panics.
func (s *MaubotSyncer) ProcessResponse(res *gomatrix.RespSync, since string) (err error) {
if !s.shouldProcessResponse(res, since) {
return
}
defer func() {
if r := recover(); r != nil {
err = fmt.Errorf("ProcessResponse panicked! userID=%s since=%s panic=%s\n%s", s.Client.UserID, since, r, debug.Stack())
}
}()
for roomID, roomData := range res.Rooms.Join {
room := s.getOrCreateRoom(roomID)
for _, event := range roomData.State.Events {
event.RoomID = roomID
room.UpdateState(event)
s.notifyListeners(event)
}
for _, event := range roomData.Timeline.Events {
event.RoomID = roomID
s.notifyListeners(event)
}
}
for roomID, roomData := range res.Rooms.Invite {
room := s.getOrCreateRoom(roomID)
for _, event := range roomData.State.Events {
event.RoomID = roomID
room.UpdateState(event)
s.notifyListeners(event)
}
}
for roomID, roomData := range res.Rooms.Leave {
room := s.getOrCreateRoom(roomID)
for _, event := range roomData.Timeline.Events {
if event.StateKey != nil {
event.RoomID = roomID
room.UpdateState(event)
s.notifyListeners(event)
}
}
}
return
}
// OnEventType allows callers to be notified when there are new events for the given event type.
// There are no duplicate checks.
func (s *MaubotSyncer) OnEventType(eventType maubot.EventType, callback maubot.EventHandler) {
_, exists := s.listeners[eventType]
if !exists {
s.listeners[eventType] = []maubot.EventHandler{}
}
s.listeners[eventType] = append(s.listeners[eventType], callback)
}
// shouldProcessResponse returns true if the response should be processed. May modify the response to remove
// stuff that shouldn't be processed.
func (s *MaubotSyncer) shouldProcessResponse(resp *gomatrix.RespSync, since string) bool {
if since == "" {
return false
}
// This is a horrible hack because /sync will return the most recent messages for a room
// as soon as you /join it. We do NOT want to process those events in that particular room
// because they may have already been processed (if you toggle the bot in/out of the room).
//
// Work around this by inspecting each room's timeline and seeing if an m.room.member event for us
// exists and is "join" and then discard processing that room entirely if so.
// TODO: We probably want to process messages from after the last join event in the timeline.
for roomID, roomData := range resp.Rooms.Join {
for i := len(roomData.Timeline.Events) - 1; i >= 0; i-- {
e := roomData.Timeline.Events[i]
if e.Type == "m.room.member" && e.StateKey != nil && *e.StateKey == s.Client.UserID {
m := e.Content["membership"]
mship, ok := m.(string)
if !ok {
continue
}
if mship == "join" {
_, ok := resp.Rooms.Join[roomID]
if !ok {
continue
}
delete(resp.Rooms.Join, roomID) // don't re-process messages
delete(resp.Rooms.Invite, roomID) // don't re-process invites
break
}
}
}
}
return true
}
// getOrCreateRoom must only be called by the Sync() goroutine which calls ProcessResponse()
func (s *MaubotSyncer) getOrCreateRoom(roomID string) *gomatrix.Room {
room := s.Store.LoadRoom(roomID)
if room == nil {
room = gomatrix.NewRoom(roomID)
s.Store.SaveRoom(room)
}
return room
}
func (s *MaubotSyncer) notifyListeners(mxEvent *gomatrix.Event) {
event := s.Client.ParseEvent(mxEvent)
listeners, exists := s.listeners[maubot.EventType(event.Type)]
if !exists {
return
}
for _, fn := range listeners {
if fn(event.Event) == maubot.StopEventPropagation {
break
}
}
}
// OnFailedSync always returns a 10 second wait period between failed /syncs, never a fatal error.
func (s *MaubotSyncer) OnFailedSync(res *gomatrix.RespSync, err error) (time.Duration, error) {
return 10 * time.Second, nil
}
// GetFilterJSON returns a filter with a timeline limit of 50.
func (s *MaubotSyncer) GetFilterJSON(userID string) json.RawMessage {
return json.RawMessage(`{"room":{"timeline":{"limit":50}}}`)
}