public Builder SetGroupIds(IEnumerable <string> ids)
            {
                var groups = new List <TGroupsFetch.Types.GroupFetch>();

                foreach (var id in ids)
                {
                    var g = new TGroupsFetch.Types.GroupFetch();
                    g.GroupId = id;
                    groups.Add(g);
                }
                message.payload = new Envelope {
                    GroupsFetch = new TGroupsFetch {
                        Groups = { groups }
                    }
                };
                return(this);
            }
            public Builder SetNames(IEnumerable <string> names)
            {
                var groups = new List <TGroupsFetch.Types.GroupFetch>();

                foreach (var name in names)
                {
                    var g = new TGroupsFetch.Types.GroupFetch();
                    g.Name = name;
                    groups.Add(g);
                }
                message.payload = new Envelope {
                    GroupsFetch = new TGroupsFetch {
                        Groups = { groups }
                    }
                };
                return(this);
            }