ons node.js调用http发送消息一直返回403

代码如下，帮忙看下哪里有问题？
var sendMsg=function(msg,cb){

var NEWLINE="\n";
msg=JSON.stringify(msg);
var topic=ali.mq.Topic;
var pid=ali.mq.Producer;
var cmd5=crypto
  .createHash('md5')
  .update(new Buffer(msg, 'utf8'))
  .digest('base64');
var date=(new Date()).getTime();
var signString=topic+NEWLINE+pid+NEWLINE+cmd5+NEWLINE+date;
var sig=signature(signString);
var options = {
  url: ali.mq.URL+'/message/?topic='+topic+'&time='+date+'&tag=http'+'&key=http',
  headers: {
    "AccessKey":ali.mq.AccessKeyId,
    "ProducerID":pid,
    "Signature":sig,       
  },
  method: 'POST',
  body:msg
};
request(options,function (error, response, body) {
  if (error||response.statusCode!==200) {
    return console.error('upload failed:', error||response.statusCode);
  }
  console.log('Upload successful!  Server responded with:', body);

})

}