Intro
OSync is a project to create a free tool for Microsoft Outlook to share calendars. Outlook does not allow its users to share the calendar by default. For this, Microsoft sells a separate product, Microsoft Exchange. When I was in Japan I had the task to enable the local office to share calendars. A long Internet search did not give me any really cheap (or free) products that worked and fitted our goals.
The idea behind the project is based on the (once free)
PIMShare.
But I never got that tool working. Either Outlook crashed or
the user accounts did not work. Quite frustrating. So in the
end I decided to write something on my own. One of many
reasons is, that PIMShare requires a registration. So I did
not know whether they would start to collect money for this
service at some later point. This fear was quite well-founded,
because only a short while after I wrote OSync, they actually
started collecting money for that service.
What I wrote about the quality of the PIMShare product above was true back in March 2004. PIMShare was under heavy development, though and it may have improved a lot.
How it works
Any calendar items to be shared are assigned a special category by the user. Every time the calendar is synchronized, an E-mail is sent out the subscribers with a list of new and deleted items. On the receiving side, this E-mails are processed to create or delete calendar items. The same user can be both receiving and sending site.
The following two Outlook calendar screenshots demonstrate how this looks. The first screenshot is from a user called "pat" and the second one from a user called "tester".
There are several noteworthy points from this example:
- The name of the person who shares the calendar is prepended in the calendar item on the receiving side.
- Repeated events are synchronized as well (see example "Another test").
- Alarms are not synchronized (see example "Just testing").
- All day events work fine (see example "Quaslimodo").
Documentation
See the OSync documentation for details on how to use it.
Project status
The release 0.1 has been published. This is early beta and might still have really nasty bugs. So if you test it and find some problems, feel free to contact me.
There are some known limitations on which I will work in the future:
- OSync always starts Outlook in the background. This should be changed so that OSync only connects to existing Outlook instances but does not start new ones.
- When an event is "unshared" (i.e. the synchronised category is removed from the category list), this change is not propagated to other clients.
Download
OSync is a Python program. There are two possibilities to download it.
- Windows Executable (3.2M)
-
This is a self-contained Windows program with no need to
install Python or anything else. Download, unzip and execute
it.
This executable was created using py2exe. - Python Source code (12K)
- You need Python to run this. Additionally the module win32com must be installed.
History
This project was started on March 18, 2004 with some brainstorming. The current release 0.1 was published on March 26.