如何确保所有功能都已完成执行并在NodeJS中发送响应？

Here is my code:

这是我的代码：

 route.get('/',function(req, res){
 for(var e = 0; e < contactEmailArray.length; e++){
        var currentContact = contactEmailArray[e];
        setSentEmailCount(gmail, currentContact);
        setReceivedEmailCount(gmail, currentContact)
    }
  //send contactEmailArray as response after everything is completed
   });

  function setSentEmailCount(gmailObject, currentContact){
    var s = gmailObject.estimatedMessages ('from:([email protected]) to:('+currentContact.email+')', { fields: []}, function(err, estimatedMessages){
    currentContact.sentEmailCount = estimatedMessages;
    console.log(currentContact.email + ' : ' + currentContact.sentEmailCount);
    sentResponseCount++;
    if(sentResponseCount == countOfContactHavingEmail){
        console.log('sent operation completed');
    }
    console.log('Counter Value : ' + sentResponseCount);
    });
 }

 function setReceivedEmailCount(gmailObject, currentContact){
    var s = gmailObject.estimatedMessages ('from: ('+currentContact.email+') to:([email protected])', { fields: []}, function(err, estimatedMessages){
    currentContact.receivedEmailCount = estimatedMessages;
    console.log(currentContact.email + ' : ' + currentContact.receivedEmailCount + ' received');
    receivedResponseCount++;
    if(sentResponseCount == countOfContactHavingEmail){
        console.log(' received operation completed');
    }
    console.log('Counter Value : ' + receivedResponseCount);
   });
 }
 route.get('/',fun