Horde SyncML Roadmap

Things that need to be worked on

Bugs/Limitations in SyncML

• Splitting a long data entry (like a 60k memo) into multiple messages is not supported when sending data to the client. However it is supported when the client sends split data.
  • When doing a SlowSync, the Server could handle a replace request by the client better than just converting it into an add: the server should check if this client sent element exists on the server. If so: replace, otherwise add.

Bugs Limitation in Horde Apps

These bugs are not directly in the SyncML module but in the various Horde applications that store the data

• Kronolith can't properly deal with more complex recurring events
  • Turba can currently sync only the default data source due to a bug in the way it stores its history

Possible Extensions

• Allow customizations which calendars/addressbooks should be synced. Maybe allow merging of more than one data source (think of private and shared calendar) (Apple has a really cool feature for multiple calendars in a palm device: Each category in the palm is one subscribed calendar in iCal. Maybe a feature like this would be great to have overlayed/group calendards)
  • Proper conflict resolution. current policy is: client wins. (As the client send it changes first.)
  • Fancy features like 'delete old entries from client calendar/todo list' etc. to save space on client.

Other stuff:

Testing Suite

The SyncML Conformance Test Suite can be downloaded from sourceforge: http://sourceforge.net/projects/oma-scts/

SyncMLConformanceTestSuite shows which test we currently pass or fail.

Cleaning up when testing

You can clear all session files (assuming the default backend) with rm -f /tmp/sess_*.

You'll have a lot of entries in the datatree with a group_uid of 'horde.history'. You will lose information from more than syncing by clearing them out, but you can do so. It is also useful to clear out horde.log and /tmp/sync to get a better feel for what is from the current sync attempt and what is not.

Links

• SyncMLDevicesFileFormats
  • SyncMLCreateTestCases: information on SyncML test cases

Debugging info

Once the current code makes it to CVS people should give it a try and check if it works. If not, the xml in /tmp/sync/, the horde log and the php error log should be helpful. If you can provide a patch to make it work: great!

Otherwise mail the offending xml and/or logs to the list. I'll have a look at it.

As many phones/pdas/whater should be thrown at the code. I'm especially interested to see the <devinf> device information section that the phones sends in its initial packet. This gets stored in /tmp/sync/syncml_client_0.xml when you start with an empty /tmp/sync/ dir.

Make sure to modify the <cred>...</cred> part in the SyncML header if it exists. It contains your username and password.

I'll try to come up with a brief "how to help with debugging" and add it to the installation docs. Otherwise we might get lots of "just installed the horde rpm and SyncML doesn't work with my XXYY phone! pls hlp!!!! I'm new to linux!!!!!" messages :-)

Data Issues

Another area where I expect problems are the various implementations of the text/x-vcalendar,vcard,... formats flying around. Basically something like

BEGIN:VNOTE

VERSION:1.1

BODY: Here's a quick note

END:VNOTE

SyncML itself doesn't understand these things: it just passes them around between the phone and the external horde api "as they come".

If you have tricky stuff like recurring events, inline photos or other exotic data in the file (or got them "treated" by Outlook), horde or your phone might quickly get a hickup. So we need to test as many of these formats as we can get our hands on.

This is more of a general horde issue than about SyncML. You can test the behaviour by trying to import/export files with this ical/vcard data into kronolith/nag/turba using their respective import/export menu entries. That should use the same codebase.

Right now as I'm writing this, I've noticed Jan creating a framework/iCalendar/tests/charset1.phpt test file. Excellent!

Timestamp and Horde API Issues

a) currently the horde api only supports listBy($action,$ts) to retrieve $actions since timestamp $ts. The SyncML protocol requires that the ending timestamp of the sync timeframe to be exchanged _before_ the actual syncing starts. So we need an additional parameter: listby($action,$ts,$ts_end)

b) the SyncML works as follows:

1) the clients sends its changes to the server

2) the server sends its changes to the client.

so when in step 2), the horde api is called with a request like "give me all changes in horde since the last sync", you get the changes induced by the client in step 1) as well. You have to somehow "tag" them to avoid echoing (and thus duplicatinging) them back to the client. Simply storing the guids in the session is not sufficient: the changes are made _after_ the end timestamp (see a)) of the current sync so you'll dupe them in the next sync. My current implementation deals with this as follows: directly after a client induced change is done in horde, state.php's gettsforAction is called to find out the biggest=latest ts for the given guid. If the horde api would provide me with this info directly (maybe just store it in a static var and provide a getLastTS() method in Driver), that would be great and eliminate costly and redundant DataTree calls. Similar in listBy where you get a list of guids but still need to retrieve the latest History timestamps for these guids manually using the DataTree so you can check out if the changes are a result of a client request or not. If listBy would return an assoc array $guid->ts that would help a lot (and solve a) as well).

Using a Palm simulator to test the Synthesis client

1. Download Palm simulator (for version 5.4) from http://www.palmos.com/dev/tools/simulator/ (free registration required).
   1. Unzip somewhere, start debug/PalmSim_54_dbg.exe, select a suitable ROM (included in debug dir)
   2. Right-click on Simulator and click Settings > Communications > Redirect SocketLib Calls to Host TCP/IP
   3. Download and unzip synthesis client for PalmOS from http://www.synthesis.ch/
   4. Install simulator by dragging the enclosed .rpc file into the simulator window.
   5. Start & configure the Synthesis client. Start a sync run.