[squid-users] Support for detecting "if-modified" using SHA digest or similar?

  Hi, I am plotting a hierarchical cache with a proxy at the client end
of a slow expensive satellite internet connection, and another on the
fast cheap internet side (goal is to optimise traffic passing through
the slow link). I would specifically like to address the issue that
many (smaller, dynamic) sites do not properly support if-modified type
headers and always send the same content each time..

I think the only way this can be solved is if the client end cache
notices it has a cached version of a resource, adds it's own
"if-modified-sha" header stating which content it's got, the upstream
proxy then may need to fetch the object again, but if the upstream finds
the content actually is the same then it commutes the response to a 304
(Something like a dynamic proxy generated e-tag really)

Someone may tell me this is already in an RFC? If so great. If not,
could someone advise how difficult this feature might be to add to Squid
3.1? Bonus marks if it doesn't break streaming resources...

Any other ways to achieve the same effect?

Thanks

Ed W
Received on Thu Jul 22 2010 - 17:06:23 MDT