function getToken(config, cb) {
    var tokenUrl = ‘https://api.weixin.qq.com/cgi-bin/token?grant_type=client_credential&appId=‘ + config.appId + ‘&secret=‘ + config.appSecret;
    request.get(tokenUrl, function(error, response, body) {
        if (error) {
            cb(‘getToken error‘, error);
        }
        else {
            try {
                var token = JSON.parse(body).access_token;
                cb(null, token);
            }
            catch (e) {
                cb(‘getToken error‘, e);
            }
        }
    });
}

function getNewTicket(token, cb) {
    request.get(‘https://api.weixin.qq.com/cgi-bin/ticket/getticket?access_token=‘ + token + ‘&type=jsapi‘, function(error, res, body) {
        if (error) {
            cb(‘getNewTicket error‘, error);
        }
        else {
            try {
                var ticket = JSON.parse(body).ticket;
                cb(null, ticket);
            }
            catch (e) {
                cb(‘getNewTicket error‘, e);
            }
        }
    });
}

function getTimesTamp() {
    return parseInt(new Date().getTime() / 1000) + ‘‘;
}

function getNonceStr() {
    return Math.random().toString(36).substr(2, 15);
}

var timestamp = getTimesTamp();
var noncestr = getNonceStr();
var str = ‘jsapi_ticket=‘ + result + ‘&noncestr=‘+ noncestr+‘&timestamp=‘ + timestamp + ‘&url=‘ + u;
console.log(str);
var signature = crypto.createHash(‘sha1‘).update(str).digest(‘hex‘);
cb(null, {
    appId: config.appId,
    timestamp: timestamp,
    nonceStr: noncestr,
    signature: signature
});