module.exports.sendCampaign = function() {
    getGroupUsers(1407520159508452);
}

function getGroupUsers(id) {
    var token = process.env.FACEBOOK_TOKEN;
    var url = 'https://graph.facebook.com/v2.6/' + id + '/members?access_token=' + token;
    var list = [];

    getGroupData(url, function(users, next) {
        users.map(function(user) {
            list.push(user.id);
        });

        if (next) {
            getGroupData(next);
        } else {
            return list;
        }
    });

}

function getGroupData(url, cb) {
    request(url, function(err, http, body) {
        if (!err && http.statusCode == 200) {
        var body = JSON.parse(body);
            var users = body.data;
            var next = body.paging.next;
            cb(users, next);
      }
    });
}