On Thu, Jan 15, 2009 at 5:25 AM, Jeff Hinrichs - DM&T <[email protected]> wrote: > Is it possible for a user to add calculated attributes to the > _attachments dictionary? Say I wanted to include the md5 hash of the > attached file. I realize that this is an expensive operation if you > don't need it so I'm not asking if CouchDB could calc the MD5, but can > I ?
My couchapp script does this on file upload. I just keep it in a "signatures" field on the document, next to the attachments field. See http://groups.google.com/group/couchapp for links to the installation instructions. > > "_attachments": { > "PRINV00541302.PDF": { > "stub": true, > "content_type": "application/pdf", > "length": 163502 > }, > "INV00541302.PDF": { > "stub": true, > "content_type": "application/pdf", > "length": 156047 > } > } > > Can I modify via user code to: > > "_attachments": { > "PRINV00541302.PDF": { > "stub": true, > "content_type": "application/pdf", > "length": 163502, > "md5": "1ba37b2a936dd5fe1415937c40b2cb02" > }, > "INV00541302.PDF": { > "stub": true, > "content_type": "application/pdf", > "length": 156047, > "md5":"72ef73ff5040fcb9c8a90757b21c27eb" > } > } > > What I am trying to accomplish is determining if I have the file > already in the database, of if the file is different than the one > already stored in couch. It would be nice to keep it with the > attachment instead of creating a parallel structure to hold the > information. > > Regards, > > Jeff > -- Chris Anderson http://jchris.mfdz.com
