Fine Uploader S3: Refused to get unsafe header "ETag"

Question

I'm trying to upload to S3 with the jQuery fineuploader (v 3.9.1) and have enabled debugging. All of the parts of the upload succeed but then I get an error "Problem asking Amazon to combine the parts!"

I've enabled debug on the console and get the errors [Refused to get unsafe header "ETag"] as well as this from Amazon:

Received response status 400 with body: InvalidPartOne or more of the specified parts could not be found. The part may not have been uploaded, or the specified entity tag may not match the part's entity tag.eTvPFvkXEm07T17tvZvFacR4vn95EUTqXyoPvlLh1a6AADlc94v7H9.a2jcmow1pjfN1xcdw_xMx60APpXn6rGwhHYtzE0NT90Bs0IVqrkaFHW75yRl5E4nfO3Od6rWZnull0CD2DC02D0870E61R4Kpfe66IDvL44Jx9Aoicxgh9Frqd4qr8ILWHbu5YhlqGomxIBOZvfkgy4R4VsYS1

Answer 1

It seems your Amazon S3 CORS XML configuration file is incorrect. Make sure you add <ExposeHeader>ETag</ExposeHeader> to the <CORSRule> section as detailed below,

<?xml version="1.0" encoding="UTF-8"?>
<CORSConfiguration xmlns="http://s3.amazonaws.com/doc/2006-03-01/">
    <CORSRule>
        <AllowedOrigin>*</AllowedOrigin>
        <AllowedMethod>POST</AllowedMethod>
        <AllowedMethod>PUT</AllowedMethod>
        <AllowedMethod>DELETE</AllowedMethod>
        <MaxAgeSeconds>3000</MaxAgeSeconds>
        <ExposeHeader>ETag</ExposeHeader>
        <AllowedHeader>*</AllowedHeader>
    </CORSRule>
</CORSConfiguration>

More information in the documentation on Amazon S3 servers and the official blog post on the same thing.