What 'Content-Type' header to use when serving gzipped files?

Question

I'm serving gzipped copies of my css / javascript files. As per a tutorial, I set the content-type as application/gzip when serving these files. However, chrome doesn't seem to un-gzip these files, and for the javascript files I get a lot of 'illegal character' errors. If I view source, I still see the files as compressed, rather than uncompressed.

My question is, what should I set as the content type for these files, in order for the browser to interpret them correctly as gzipped css / js files, and un-gzip them? If I just set text/javascript or text/css, will the browser still interpret them correctly?

Edit: Full response headers:

HTTP/1.1 200 OK
x-amz-id-2: UIBkZT/MuFxsmn+3nVOzEO63rRY99l3traCbMExUgSdGHUrOIPtNp34h1+ujYKmt
x-amz-request-id: 19346C9B01D8FC62
Date: Mon, 12 May 2014 03:59:51 GMT
Content-Encoding: gzip
Last-Modified: Mon, 12 May 2014 02:24:54 GMT
ETag: "561080b5e19f6daea2e74fd5a0623c79"
Accept-Ranges: bytes
Content-Type: application/x-gzip
Content-Length: 5153
Server: AmazonS3

Dibbell

Answer 1

Compressed content in the response is indicated in the Content-Encoding. The Content-Type should remain the same, that is, it should reflect the underlying media type that is compressed.

Content-Type: application/javascript
Content-Encoding: gzip

See sections 14.11 Content-Encoding and 3.5 Content Codings of RFC 2616 for more information.

Mease

I'm already doing that, but it still seems to be not interpreting the script correctly. I've edited to put the full headers in the question – Dibbell

It gives the error Uncaught SyntaxError: Unexpected token ILLEGAL on line 1, and when I check it, I see that it has the file name at that line, e.g �� aRjquery-1.7.1.min.js�}. I compressed the files using gzip -9, do I need to gzip using a lower setting? Or do I need to delete the filenames from the start of file? – Dibbell

OK, I see the expected Content-Encoding, but the Content-Type should reflect the underlying media type that is compressed. Try changing application/x-gzip back to application/javascript. – Mease

I also see AmazonS3 is the server. Perhaps #5442511 is also relevant. – Mease