Just did a quick search. Looks like you can put an MD5 checksum into the headers with Apache quite easily: http://httpd.apache.org/docs/2.2/mod/core.html#contentdigest
Haven't played with it yet, but the doco does indicate a bit of a performance hit as it doesn't cache the checksums... Not suprising since content could be dynamically generated. Greg On Jul 1, 8:17 pm, David Schmitt <da...@dasz.at> wrote: > Robin Sheat wrote: > > On Wednesday 01 July 2009 14:14:36 Greg wrote: > >> The main question would be in terms of how to detect file changes > >> without a full transfer - HTTP does provide some mechanisms for > >> checking this, but I'm not sure if they would be adequate if scripting > >> responses through HTTP... > > > I use S3 as a file source for my larger files, it allows contents to be > > verified by MD5. My code for this is available here: > >https://code.launchpad.net/~eythian/+junk/ec2facts > > it's pretty basic, but gets the job done. > > > I mention this because a similar approach should be usable when backing with > > HTTP and Apache. You could either do a HEAD request with > > 'If-Modified-Since', > > and ensure that when you save the file, you update the file timestamp to > > that > > supplied by apache, or check to see if apache will provide the MD5 (or > > whatever) hash of the file contents. If the HEAD request indicates that > > there > > is an updated version, then you pull it down using wget or similar. > > The two classical approaches to this are either properly configured ETag > support or using the checksum as part of the filename and never refetch > a file unless its filename has changed. > > Regards, DavidS --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Puppet Users" group. To post to this group, send email to puppet-users@googlegroups.com To unsubscribe from this group, send email to puppet-users+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/puppet-users?hl=en -~----------~----~----~----~------~----~------~--~---
