猫鼬的承诺不会将数据传递到下一个链

Question

I am querying MongoDB using mongoose with promise. The result is accessible only in the first .then(function(results){ // can send the result from here..}) . But when I manipulate the results and pass it to the next .then() chain it is not accessible. Below is the full function.

exports.getAcl = function(req, res) {

  User.findAsync({}, {
    acl: 1
  })
  .then(function(results){
    var aclList = [];
    results.forEach(function(result,index,arr){
      aclList[result._id] = result;
      if (index === (arr.length - 1)) {
        console.log('I can log the aclList here..', aclList)
        return aclList // But neither able to send it to next chain nor to front end res.send(aclList) 
      }
    })
  })
  .then(function(aclList){
    console.log(aclList) // Loging undefined
    res.status(200).json(aclList); // undefined
  })
  .catch(handleError(res));
}

Please let me know what I am doing wrong here..thanks

Answer 1

Instead of

results.forEach(function(result,index,arr){
  aclList[result._id] = result;
  if (index === (arr.length - 1)) {
    console.log('I can log the aclList here..', aclList)
    return aclList // But neither able to send it to next chain nor to front end res.send(aclList) 
  }
})

try

var resArray = [];
results.forEach(function(result,index){
  aclList[result._id] = result;
  if (index === (arr.length - 1)) {
    newRes.push(aclList);
  }
})
// console.log(resArray) to verify they are there
return resArray;

Bottom line: don't use multiple returns per function (as in forEach ).