Only download list-files if they've been modified.

[GoogleCodeExporter]

To help decrease the bandwidth costs associated with list providers
(iblocklist, bluetack, etc.), we should look into trying to download
list-files only if they've been marked as changed on the server.

In theory this should be doable by having PeerBlock check the HTTP Header
of the file prior to downloading it, but this requires that a server
correctly support that.  We need to be careful to make sure we test this
against as many blocklist-servers as we can find, and make sure that we can
handle the case where this is NOT being set as well, just in case.

See
(http://stackoverflow.com/questions/204886/can-i-use-http-header-to-check-if-a-d
ynamic-page-has-been-changed)
for some discussion of a possible implementation of this.

Original issue reported on code.google.com by peerbloc...@gmail.com on 8 Oct 2009 at 1:14

[GoogleCodeExporter]

Has this already been implemented? I'm managing a personal list with some 
colleagues on 
Google Docs, using the "export as txt" function to link Peer Block to the 
dynamic file. 
This worked wonderfully but I recently made some additions but Peer Block 
constantly 
states "no update needed".

If you need reference, the address we use is 
http://docs.google.com/MiscCommands?
command=saveasdoc&docID=0AR5f6sit0gtIZGRtOWcya3dfM2Y1NDQ1amhy&exportFormat=txt

Original comment by e.lammer...@gmail.com on 17 Oct 2009 at 2:02

[GoogleCodeExporter]

"Peer Block constantly states "no update needed"."

PeerBlock checks for list-updates no more often than once every 12 hours, even 
if
you're manually telling it to update lists via the "Check Updates" button.  
What I'd
imagine was happening for you was simply that PeerBlock had already recently 
checked
for updates to this file, and refused to check again in order to keep us from
hammering on list-hosting servers.

Original comment by peerbloc...@gmail.com on 30 Oct 2009 at 2:25

[GoogleCodeExporter]

Looks like this functionality was already implemented, way back in the PG2 days 
of
the code.  My bad for adding this before checking on that.

Original comment by peerbloc...@gmail.com on 8 Jan 2010 at 4:20

• Changed state: Invalid