HTTP_ConditionalGet
Notes
How to distinguish 200 and 304 responses
For these pages all 200 responses are sent in chunks a second apart, so you
should notice that 304 responses are quicker. You can also use HTTP sniffers
like Fiddler (win) and
LiveHTTPHeaders (Firefox add-on)
to verify headers and content being sent.
Browser notes
- Opera
- Opera has a couple behaviors against the HTTP spec: Manual refreshes (F5)
prevents the ETag/If-Modified-Since headers from being sent; it only sends
them when following a link or bookmark. Also, Opera will not honor the
must-revalidate
Cache-Control value unless max-age
is set. To get Opera to follow the spec, ConditionalGet will send Opera max-age=0
(if one is not already set).
- Safari
- ETag validation is unsupported, but Safari supports HTTP/1.0 validation via
If-Modified-Since headers as long as the cache is explicitly marked
"public" or "private" ("private" is default in ConditionalGet).