Backlog several pages of messages if not initial backlog

1 files changed, 50 insertions, 17 deletions

diff --git a/connector/mattermost/mattermost.go b/connector/mattermost/mattermost.go
index 51ad636..0b863fb 100644
--- a/connector/mattermost/mattermost.go
+++ b/connector/mattermost/mattermost.go
@@ -27,6 +27,9 @@ type Mattermost struct {
 	username string
 	teams    map[string]bool
 
+	initial_members int // How many room members (maximum) to load when first joining a channel
+	initial_backlog int // How many previous messages (maximum) to load when first joining a channel
+
 	conn            *matterclient.MMClient
 	handlerStopChan chan bool
 
@@ -66,6 +69,16 @@ func (mm *Mattermost) Configure(c Configuration) error {
 		return err
 	}
 
+	mm.initial_members, err = c.GetInt("initial_members", 1000)
+	if err != nil {
+		return err
+	}
+
+	mm.initial_backlog, err = c.GetInt("initial_backlog", 1000)
+	if err != nil {
+		return err
+	}
+
 	teams, err := c.GetString("teams")
 	if err != nil {
 		return err
@@ -385,7 +398,7 @@ func (mm *Mattermost) initSyncChannel(ch *model.Channel) {
 
 		// Update member list
 		// TODO (when this will be slow, i.e. hundreds of members): do only a diff
-		members, resp := mm.conn.Client.GetChannelMembers(ch.Id, 0, 1000, "")
+		members, resp := mm.conn.Client.GetChannelMembers(ch.Id, 0, mm.initial_members, "")
 		if resp.Error == nil {
 			for _, mem := range *members {
 				if mem.UserId == mm.conn.User.Id {
@@ -405,26 +418,45 @@ func (mm *Mattermost) initSyncChannel(ch *model.Channel) {
 	}
 
 	// Read backlog
-	var backlog *model.PostList
-	var resp *model.Response
 	last_seen_post := mm.handler.CacheGet(fmt.Sprintf("last_seen_%s", ch.Id))
 	if last_seen_post != "" {
-		backlog, resp = mm.conn.Client.GetPostsAfter(ch.Id, last_seen_post, 0, 1000, "")
-		// TODO: if there are more than 1000, loop around
-	} else {
-		backlog, resp = mm.conn.Client.GetPostsForChannel(ch.Id, 0, 1000, "")
-	}
-	if resp.Error == nil {
-		for i := 0; i < len(backlog.Order); i++ {
-			post_id := backlog.Order[len(backlog.Order)-i-1]
-			post := backlog.Posts[post_id]
-			post_time := time.Unix(post.CreateAt/1000, 0)
-			post.Message = fmt.Sprintf("[%s] %s",
-				post_time.Format("2006-01-02 15:04:05 MST"), post.Message)
-			mm.handlePost(ch.Name, post, true)
+		const NUM_PER_PAGE = 100
+		page := 0
+		backlogs := []*model.PostList{}
+		for {
+			backlog, resp := mm.conn.Client.GetPostsAfter(ch.Id, last_seen_post, page, NUM_PER_PAGE, "")
+			if resp.Error == nil {
+				backlogs = append(backlogs, backlog)
+				if len(backlog.Order) == NUM_PER_PAGE {
+					page += 1
+				} else {
+					break
+				}
+			} else {
+				break
+			}
+		}
+		for i := 0; i < len(backlogs); i++ {
+			mm.processBacklog(ch, backlogs[i])
 		}
 	} else {
-		log.Warnf("Could not get channel backlog: %s", resp.Error)
+		backlog, resp := mm.conn.Client.GetPostsForChannel(ch.Id, 0, mm.initial_backlog, "")
+		if resp.Error == nil {
+			mm.processBacklog(ch, backlog)
+		} else {
+			log.Warnf("Could not get channel backlog: %s", resp.Error)
+		}
+	}
+}
+
+func (mm *Mattermost) processBacklog(ch *model.Channel, backlog *model.PostList) {
+	for i := 0; i < len(backlog.Order); i++ {
+		post_id := backlog.Order[len(backlog.Order)-i-1]
+		post := backlog.Posts[post_id]
+		post_time := time.Unix(post.CreateAt/1000, 0)
+		post.Message = fmt.Sprintf("[%s] %s",
+			post_time.Format("2006-01-02 15:04:05 MST"), post.Message)
+		mm.handlePost(ch.Name, post, true)
 	}
 }
 
@@ -569,6 +601,7 @@ func (mm *Mattermost) handlePost(channel_name string, post *model.Post, only_mes
 		}
 
 		mm.handler.Event(msg_ev)
+		mm.handler.CachePut(fmt.Sprintf("last_seen_%s", post.ChannelId), post.Id)
 	} else {
 		interested, roomId := mm.reverseRoomId(post.ChannelId)
 		if !interested {