Check file size on S3 without downloading?

I have customer files uploaded to Amazon S3, and I would like to add a feature to count the size of those files for each customer. Is there a way to "peek" into the file size without downloading them? I know you can view from the Amazon control panel but I need to do it pro grammatically.

Solution 1:

Send an HTTP HEAD request to the object. A HEAD request will retrieve the same HTTP headers as a GET request, but it will not retrieve the body of the object (saving you bandwidth). You can then parse out the Content-Length header value from the HTTP response headers.

Solution 2:

Node.js example:

const AWS = require('aws-sdk');
const s3 = new AWS.S3();

function sizeOf(key, bucket) {
    return s3.headObject({ Key: key, Bucket: bucket })
        .promise()
        .then(res => res.ContentLength);
}


// A test
sizeOf('ahihi.mp4', 'output').then(size => console.log(size));

Doc is here.