如何检查Node.JS AWS Lambda数据？

Question

I am new to both Lambda and Node.JS. I originally wanted to write the function in Python, but boss says he'd like it in Node. I am writing an AWS Lambda function to turn off specified EC2 instances at the end of the day. I am having trouble inspecting if describeInstances is grabbing the correct data.

Right now the code shows return String(instances); but I've tried numerous different things such as return instances.response.data; which gives an error about trying to stringify the data or something.

var AWS = require('aws-sdk');
var ec2 = new AWS.EC2();
AWS.config.update({region: 'us-west-2'});

exports.handler = async (event) => {

 var params = {
  Filters: [
     {
    Name: "tag:Parking", 
    Values: [
       "true"
    ]
   }
  ]
 };

var instances = ec2.describeInstances(params, function(err, data) {
   if (err) console.log(err, err.stack); // an error occurred
   else return data; // successful response
 });

 //return Object.getOwnPropertyNames(instances);
 //return instances.response.httpResponse;
 return String(instances);
};

I just want to be able to view a list of the returned EC2 instances to see if I have the correct instances before turning them off.

Answer 1

describeInstances returns an AWS.Request object not the actual results of the operation, which are returned in the callback handler you passed to the describeInstances function.

You can do it like this using async/await syntax

const data = await ec2.describeInstances(params).promise();
return data

Answer 2

You should be able to view the logs in the AWS Console. The easiest way is to go to the Lambda console, select the function in question, click "Monitoring" near the top left, and then "View logs in CloudWatch" just below that to the right.