Re: metastore
- From
Julian Phillips <julian@quantumfyre.co.uk>
- Date
- Oct 2, 2007, 23:32 UTC
- Message-ID
- <Pine.LNX.4.64.0710030018240.4087@reaper.quantumfyre.co.uk>
- In-Reply-To
- <20071002211518.GA10445@hardeman.nu>
On Tue, 2 Oct 2007, David Härdeman wrote:
Show 38 quoted lines
> On Tue, Oct 02, 2007 at 10:04:56PM +0200, David Kastrup wrote: >> David Härdeman <david@hardeman.nu> writes: >> >> > On Tue, Oct 02, 2007 at 08:53:01PM +0100, martin f krafft wrote: >> > > also sprach David Härdeman <david@hardeman.nu> [2007.09.19.2016 +0100]: >> > > > But I agree, if any changes were made to git, I'd advocate adding >> > > > arbitrary attributes to files (much like xattrs) in name=value >> > > > pairs, then any extended metadata could be stored in those >> > > > attributes and external scripts/tools could use them in some way >> > > > that makes sense...and also make sure to only update them when it >> > > > makes sense. >> > > >> > > So where would those metdata be stored in your opinion? >> > >> > I'm not sufficiently versed in the internals of git to have an >> > informed opinion :) >> >> I think we have something like a length count for file names in index >> and/or tree. We could just put the (sorted) attributes after a NUL >> byte in the file name and include them in the count. It would also >> make those artificially longer file names work more or less when >> sorting them for deltification. > > Or perhaps the index format could be extended to include a new field for > value=name pairs instead of overloading the name field. > > But as I said, I have no idea how feasible it would be to change git to > support another arbitrary length field in the index/tree file. > >> However, this requires implementing _policies_: it must be possible to >> specify per repository exactly what will and what won't get tracked, >> or one will get conflicts that are not necessary or appropriate. > > I think the opposite approach would be better. Let git provide set/get/delete > attribute operations and leave it at that. Then external programs can do what > they want with that data and add/remove/modify tags as necessary (and also > include the smarts to not, e.g. remove the permissions on all files if the > git repo is checked out to a FAT fs).
You need more than that. You need to be able to log, blame etc on the attributes. One of the big annoyances of Subversion properties is being unable to find out when or why a property value was changed.
I still don't see why the attributes need to be stored in git directly - particularly if you are going to use an external program to actually apply any settings - why not store the attributes as normal file (or files) of some sort tracked by git? You could use any number of methods - e.g. use an sqlite database stored in the root of your tree, or a .<name>.props file alongside each path that you have properties for. You could even write a system that uses such a method and was then SCM agnostic, allowing you to keep your attribute tracking system if/when something better than git comes along - or simply share it with less-fortunate souls stuck in an inferior system.
-- Julian --- A strong conviction that something must be done is the parent of many bad measures. -- Daniel Webster