[coldsync-hackers] ColdSync 1.5.0 snapshot (and RFC)

[Andrew Arensburger <arensb+CShackers@ooblick.com>]

	Just to prove to everyone that I haven't quite disappeared from
the face of the earth, I've just uploaded a new ColdSync snapshot:
http://www.ooblick.com/software/coldsync/coldsync-1.5.0-20001111.tar.gz
	This should be considered alpha-quality software. Don't use it on
important data.

	The main changes are the following:
	- There is a new "-m<mode>" option, which determines in which
	  mode ColdSync will run:
	- "coldsync -ms" (Sync or Standalone mode) is the default.
	  This is the normal sync.
	- "coldsync -mb <dir> [file...]" (Backup mode) reads databases
	  from the Palm and writes them to <dir>. If individual
	  databases are named, only those databases are backed up.
	- "coldsync -mr [file...]" (Restore mode) copies the named
	  files to the Palm, without any modifications. If the file is
	  a directory, installs all of the databases in that
	  directory. This can be used to install new databases.
	- For now, ColdSync does not update the username and userid on
	  the Palm. This will be handled by a future Init mode.
	- Added John-David Smith's Install conduits. These provide a
	  hook for actions to be taken when installing a database.
	  (When you're looking at the code, bear in mind that he wrote
	  the code before I ripped main() apart and rewrote it from
	  scratch. So John-David Smith gets credit for writing this
	  code, and I get the blame for breaking it.)

Request for comments:

* Init mode:

	ColdSync currently suffers from the "Bargle bug", where if you
  reset your Palm, ColdSync thinks that you've erased everything, and
  deletes your backup. In addition, several people have complained
  that, since ColdSync sets your user name and ID to your name and uid
  from /etc/passwd, that this causes problems with HotSync.
	To address both of these issues, I want to do the following:
	- Before a normal sync, ColdSync will check the user name and
	  ID on the Palm. If a username and/or userid have been
	  specified in the appropriate pda {} block, and they don't
	  match what's on the Palm, ColdSync will abort. Also, if the
	  userid is 0, ColdSync will abort (this should prevent the
	  Bargle bug).
	- I want to add an Init mode to allow you to set the username
	  and userid. When you run 'coldsync -mI' (with no other
	  options), ColdSync will connect to the Palm, find an
	  appropriate pda {} block in .coldsyncrc, and set the
	  username and userid from there.
		If it can't find a username or userid in .coldsyncrc,
	  it will default to the current user's name and uid from
	  /etc/passwd.
		Question: how else should one be able to specify the
	  username and userid? Command-line options? Interactive
	  query?
		Bear in mind that all user interaction should happen
	  before ColdSync talks to the Palm, since "keepalive" packets
	  aren't implemented yet, and the user's response could take
	  an arbitrarily long time.

* Install conduits:

	The way Install conduits currently work (or should work) is as
  follows: ColdSync looks at each file in ~/.palm/install in turn, and
  runs all applicable Install conduits defined in .coldsyncrc . An
  Install conduit can modify its input database, upload records
  directly to an existing database on the Palm, add records to
  databases in the backup directory, delete the input database, or
  anything else it likes.
	After the Install conduits have run, ColdSync takes a second
  look at ~/.palm/install, and uploads anything that's still there.
	The intent is to allow Install conduits to control how a given
  database gets installed. For instance, if you want to incorporate
  all of your friend's addresses, you can just plunk his AddressDB.pdb
  into ~/.palm/install , and a conduit will add its contents to
  ~/.palm/backup/AddressDB.pdb, then delete
  ~/.palm/install/AddressDB.pdb .

	Question: Let's say that your site administrator has just
  dropped a copy of the corporate directory in your
  ~/.palm/install/AddressDB.pdb . However, you prefer to use the
  SuperAddressBook application, so you write an Install conduit to
  convert ~/.palm/install/AddressDB.pdb to
  ~/.palm/install/SuperAB.pdb. After ColdSync runs the Install
  conduits for AddressDB.pdb, should it also run the Install conduits
  for SuperAB.pdb ? Or should it assume that if you just created it,
  then you know what you're doing?

	Question: one thought that crossed my mind was that of adding
  another built-in conduit, "[install]", which installs its database,
  and make it a default conduit, so that by default, ColdSync will
  install new files in the normal way. This would allow you to do
  something like:
	conduit install {
		type: Supe/Addr;
		path: /conduits/address-preprocessor;
	}
	conduit install {
		type: Supe/Addr;
		path: [install];
	}
	conduit install {
		type: Supe/Addr;
		path: /conduits/address-postprocessor;
	}
  The danger here is that if you forget to invoke "[install]"
  explicitly after your own conduit, the file will still be there, and
  ColdSync will try to reinstall it the next time you sync.

	Question: currently, if an Install conduit deletes its input
  database, that means that it has taken care of installing it (or
  whatever). What if you have two conduits:
	conduit install {
		type: Foox/Barx;
		path: /conduits/first;
	}
	conduit install {
		type: Foox/Barx;
		path: /conduits/second;
	}
  If /conduits/first deletes its input database, should
  /conduits/second still run?

--
Andrew Arensburger                      This message *does* represent the
arensb@ooblick.com			views of ooblick.com
       Time spent at cons does not count against your lifespan.


-- 
This message was sent through the coldsync-hackers mailing list.  To remove
yourself from this mailing list, send a message to majordomo@thedotin.net
with the words "unsubscribe coldsync-hackers" in the message body.  For more
information on Coldsync, send mail to coldsync-hackers-owner@thedotin.net.