How To Get Last Modified Timestamp Of An External File?

How to get last modified timestamp of an external file? I'm trying to use using xhr.getResponseHeader('Last-Modified'), and I am getting the pervious modified time, but not the rec

Solution 1:

You can use get response as a Blob, pass Blob to File constructor to get .lastModifiedDate property value

fetch("/path/to/file")
.then(response => response.blob())
.then(blob => {
  const file = new File([blob], blob.name);
  console.log(file.lastModifiedDate, file.lastModified);
});