Check file size on S3 without downloading?

Question

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.

Answer 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.

Answer 2

You can also do a listing of the contents of the bucket. The metadata in the listing contains the file sizes of all of the objects. This is how it's implemented in the AWS SDK for PHP.