CODEWITHSUNDEEP
httpcachingamazon-s3
Geo
Geo

Reputation: 96957

Why is my browser doing a request if I've configured the expires and cache control headers?

This is an example response from my amazon bucket. 

$ curl -I http://amazon_bucket/image.jpg
HTTP/1.1 200 OK
x-amz-id-2: Tmr9SynKe8ztlB/Jix1hNrclwyc/k4NVHyqK3B0vNKUoPFIxfzwALi0XQRwEjhzO
x-amz-request-id: DCFDBCF510988AFB
Date: Wed, 27 Mar 2013 13:06:34 GMT
Cache-Control: public, max-age=2629000
Expires: Wed, 26 Mar 2014 23:00:00 GMT
Last-Modified: Wed, 27 Mar 2013 13:00:19 GMT
ETag: "52dd53ea738c7824b3f67cfea6a3af2a"
Accept-Ranges: bytes
Content-Type: image/jpeg
Content-Length: 627046
Server: AmazonS3

I would expect the browser to cache the image and serve it from cache. Instead, when I reload the page, my browser does a request, which yield a 304 not modified response. Why is it acting like must-revalidate option was passed? Why isn't the browser serving the image directly from cache? The options I've configured on the image, from my S3 client are these:

Cache-Control: public, max-age=2629000
Expires: Wed, 26 Mar 2014 23:00:00 GMT

Is there some other option I should be passing to the S3 files? It might be a dumb answer, but I see that the requests my browser makes to get these pictures all have the following headers:

Cache-Control:no-cache
Pragma:no-cache

Why is my browser sending those?

Upvotes: 0

Views: 191

Answers (1)

Geo
Geo

Reputation: 96957

I was hitting refresh, and apparently, this always triggers an If-Modified-Since request. If you visit the page normally, the asset is served from browser cache.

Upvotes: 2

Related Questions