add server methods getRoomNameById

server/methods/getRoomNameById.js

@@ -0,0 +1,32 @@
+Meteor.methods({
+	getRoomNameById(rid) {
+		check(rid, String);
+
+		if (!Meteor.userId()) {
+			throw new Meteor.Error('error-invalid-user', 'Invalid user', {
+				method: 'getRoomNameById'
+			});
+		}
+
+		const room = RocketChat.models.Rooms.findOneById(rid);
+
+		if (room == null) {
+			throw new Meteor.Error('error-not-allowed', 'Not allowed', {
+				method: 'getRoomNameById'
+			});
+		}
+
+		const user = Meteor.user();
+		if (user && user.username && room.usernames.indexOf(user.username) !== -1) {
+			return room.name;
+		}
+
+		if (room.t !== 'c' || RocketChat.authz.hasPermission(Meteor.userId(), 'view-c-room') !== true) {
+			throw new Meteor.Error('error-not-allowed', 'Not allowed', {
+				method: 'getRoomNameById'
+			});
+		}
+
+		return room.name;
+	}
+});