APIv4 post /channels/ids (#5845)

* APIv4 post /channels/ids

* updated enpoint as /teams/{team_id}/channels/ids

api4/channel.go

@@ -19,8 +19,9 @@ func InitChannel() {
 	BaseRoutes.Channels.Handle("/direct", ApiSessionRequired(createDirectChannel)).Methods("POST")
 	BaseRoutes.Channels.Handle("/members/{user_id:[A-Za-z0-9]+}/view", ApiSessionRequired(viewChannel)).Methods("POST")
 
-	BaseRoutes.Team.Handle("/channels", ApiSessionRequired(getPublicChannelsForTeam)).Methods("GET")
-	BaseRoutes.Team.Handle("/channels/search", ApiSessionRequired(searchChannelsForTeam)).Methods("POST")
+	BaseRoutes.ChannelsForTeam.Handle("", ApiSessionRequired(getPublicChannelsForTeam)).Methods("GET")
+	BaseRoutes.ChannelsForTeam.Handle("/ids", ApiSessionRequired(getPublicChannelsByIdsForTeam)).Methods("POST")
+	BaseRoutes.ChannelsForTeam.Handle("/search", ApiSessionRequired(searchChannelsForTeam)).Methods("POST")
 	BaseRoutes.User.Handle("/teams/{team_id:[A-Za-z0-9]+}/channels", ApiSessionRequired(getChannelsForTeamForUser)).Methods("GET")
 
 	BaseRoutes.Channel.Handle("", ApiSessionRequired(getChannel)).Methods("GET")
@@ -322,6 +323,38 @@ func getPublicChannelsForTeam(c *Context, w http.ResponseWriter, r *http.Request
 	}
 }
 
+func getPublicChannelsByIdsForTeam(c *Context, w http.ResponseWriter, r *http.Request) {
+	c.RequireTeamId()
+	if c.Err != nil {
+		return
+	}
+
+	channelIds := model.ArrayFromJson(r.Body)
+	if len(channelIds) == 0 {
+		c.SetInvalidParam("channel_ids")
+		return
+	}
+
+	for _, cid := range channelIds {
+		if len(cid) != 26 {
+			c.SetInvalidParam("channel_id")
+			return
+		}
+	}
+
+	if !app.SessionHasPermissionToTeam(c.Session, c.Params.TeamId, model.PERMISSION_VIEW_TEAM) {
+		c.SetPermissionError(model.PERMISSION_VIEW_TEAM)
+		return
+	}
+
+	if channels, err := app.GetPublicChannelsByIdsForTeam(c.Params.TeamId, channelIds); err != nil {
+		c.Err = err
+		return
+	} else {
+		w.Write([]byte(channels.ToJson()))
+	}
+}
+
 func getChannelsForTeamForUser(c *Context, w http.ResponseWriter, r *http.Request) {
 	c.RequireUserId().RequireTeamId()
 	if c.Err != nil {