Hi there,

I'm currently trying to think through how to implement IKeyReference for files on the filesystem. The end goal is to be able to use the intids service on these files, so that they can be cataloged.

The simplistic approach to implement key references for files is simply to use the filesystem path as key reference: the path is easy to determine, and it's easy to resolve back to the file.

Unfortunately this doesn't work in the case where the files can be moved on the filesystem.

I foresee two scenarios in which files could be moved: one through a web UI (sending out the appropriate IObjectMovedEvent and so on). The other is on the filesystem, were files could be moved during, for instance, an SVN update (the idea is to be able to store the file data in SVN but expose it as Zope-ish objects).

The scenario of the UI is more important to me so let's forget about non-UI moves for a moment.

Suddenly, using a filesystem path for IKeyReference becomes broken. When a file moves, the keyreference breaks.

One solution would be to create a special index that lists to all the appropriate move events and updates the paths. This would be somewhat similar to the way the ZCatalog maintains itself. It just seems annoying to have to write an index to be able to index. :) Getting this right is somewhat tricky.

Another approach involves storing unique ids of some kind inside the files themselves. This would be a possibility, but of course a move shouldn't require a full directory walk in order to find the file of a particular id again. It would help with filesystem level moves somewhat but I said I wasn't going to worry about them. It would still require the creation of a separate index.

Now I'm hoping I'm missing some kind of strategy and perhaps someone will have a luminous idea to make this work without the creation of a separate index. Or if not, at least I can give up looking and just go and write that index. Does anyone have any suggestions?



Zope3-dev mailing list
Unsub: http://mail.zope.org/mailman/options/zope3-dev/archive%40mail-archive.com

Reply via email to