On 2014-03-30 23:10, Fahim Mohammed wrote:
Hi all, Could you please give me some tip / point me in the direction of how i can achieve the following? I need squid to redirect certain download types to a download manager like aria2 or axel - which will download the file using segmented downloading and pass the file to squid or to the user who requested the file. Do hope that the question is clear and that someone will be able to help out. Thanks a bunch :)
Opening certain URLs in an application is a web browser or OS feature. By the time Squid gets the request it is already being processed by whatever client application the end-user has.
Also, you may seriously want to reconsider this proposal. Download managers using "segmented downloading" (I assume that means Range requests or some equivalent?) *break* HTTP in several ways ...
* Other clients downloading those same URLs end up with worse response times as they cannot get HIT responses on an earlier clients full-object request.
* Other clients downloading *other* URLs also get a speed/bandwidth penalty as the download manager forces extra connections through the proxy. The proxy will slow down when it nears TCP socket limits and as its total connection count rises (more work to do == slower per-connection handling for everyone).
* The proxy may un-segment each of the N separate requests made by the download manager in order to fetch the entire object and cache it. Resulting in much more bandwidth consumption on the Proxy<->Server network until the first URL request is cached. Following which the download manager receives multiple responses in the *same* time the proxy could have delivered as HIT. (ie. up to twice as long to deliver the object than normal HTTP/1.1 would have. yay.)
The Axel page has a hint about other problems "It doesn't pass the correct headers from the client to the server yet". To me that reads as meaning that HTTP/1.1 performance features are unlikely to work properly due to header brokenness, possibly even cross-site security issues as well.
Download managers were never a good idea for HTTP protocol fetches. A lot of content generation and delivery work is placed upon the intermediaries and server under normal protocol handling. Increasing that work N-fold to benefit a single client is a bad idea that backfires in some obscure ways.
Amos
