Thank you, Matt, for inspecting that and for the continued explanation. If I have a local and S3 file pair and the local file is modified such that size is not modified, but its date is, a sync with aws cli would copy that modified local file over the existing s3 counterpart (due to the source file having a newer mtime when compared to S3 LastModified), but a sync with s3cmd --no-check-md5 (which I unfortunately often have to use) would not.
Is this statement accurate? Mike On Apr 14, 2014, at 6:51 PM, Matt Domsch <m...@domsch.com> wrote: > aws-cli (after a quick perusal of their source code) uses the LastModified > value (set by S3 to be the time the upload of the object occurred) on objects > in S3, which is obtainable from the <ListBucket> XML, without doing a HEAD > call. They then go on to calculate the difference between LastModified and > stat.mtime(), accounting for time zone differences. local files use > stat.mtime. > > aws-cli then proceeds to compare the two values; if LastModified is newer > than stat.mtime, syncing local->remote is skipped (the remote is newer than > local); likewise on download, if LastModified is older than the local file, > it too is skipped. > > Neither tool sets LastModified = stat.mtime on upload (nor can they). s3cmd > gets around this by setting stat.mtime into the file's metadata when > --preserve (the default) is used, but then would have to use a HEAD or GET > call to get it back. s3cmd does update the local on-disk mtime and atime > when downloading (GETting), because we get the header back, and that's free > then. Likewise, aws-cli sets both mtime and atime = LastModified on download. > > So aside from aws-cli skipping over newer files in destination, I think their > behavior is identical. > > > > > > ------------------------------------------------------------------------------ > Learn Graph Databases - Download FREE O'Reilly Book > "Graph Databases" is the definitive new guide to graph databases and their > applications. Written by three acclaimed leaders in the field, > this first edition is now available. Download your free book today! > http://p.sf.net/sfu/NeoTech_______________________________________________ > S3tools-general mailing list > S3tools-general@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/s3tools-general -- wag...@wagnerone.com "Never fall into the trap of judging that which you don't understand as nonsense. That error can destroy you."-Feist ------------------------------------------------------------------------------ Start Your Social Network Today - Download eXo Platform Build your Enterprise Intranet with eXo Platform Software Java Based Open Source Intranet - Social, Extensible, Cloud Ready Get Started Now And Turn Your Intranet Into A Collaboration Platform http://p.sf.net/sfu/ExoPlatform _______________________________________________ S3tools-general mailing list S3tools-general@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/s3tools-general
