OAA wrapper for handling calendar files

Andreas Wallentin

G�teborg University Department of Linguistics under the TALK project

December 2004

OAA wrapper for handling calendar(iCal,KOrganizer) files

This OAA wrapper handles files for calendar applications such as iCal and KOrganizer. It builds new calendar files or updates existing ones. The wrapper does not interact with a database, instead it saves the necessary information as a binary file. From this binary file one can build new calendar files in VCalendar format (*.ics). If the use has existing calendar files, the wrapper can take one of those and load it into the application, giving the user the chance to update it.

Over all functionality

The user uses OAA when updating his calendar files. These files are then used in other stand alone calendar applications. As default suffix to these file we will use .ics''. When using this wrapper, a default database is used. The database is updated automatically every time an entry is added or deleted. The binary database file will be placed in, logically from the directory of the java call, dbs/db.sav.

So far the user can add events, todos and alarms into the calendar using the add/3 and add/4 methods. In the near future there will only be events to add, using the addEvent/5 method. When adding to the database an Id number is also added automatically into the entry. This is used to simplify the delete method. When the user has added his information, the database entries will look like the following examples: entry( event(Summary,Id,startDate(StartDate),endDate(EndDate)) ) or entry( todo(Summary,Id,startDate(StartDate)) ) For format of the input, see the solvables below.

The wrapper will probably not be able to parse all type of calendar files. The ones used, both when parsing and generating, are very simple with less information that is customary. However, the parser is to be updated shortly.

For additional information, see the API for the wrapper classes or the source files. There will be examples of test runs further down.

These are the solvables that are available to the wrapper:

• add(+Type,+Summary,+StartDate)
• add(+Type,+Summary,+StartDate,+StopDate)
• addEvent(+Type,+Summary,+StartDatime,+EndDatime,+Location)
• entry(?X)
• delete(+Id)
• buildCal(+CalendarFileName)
• buildDb(+ExistingCalendarFileName)

The add solvable comes in three versions. The first, add(Type,Summary,StartDate), is handling the todos and alarms. What this solvable needs is representation of what type it is (todo or alarm), summary of the entry and a start date. All representation must be strings, even the date. The date format takes the YearMonthDay and the time of day which will look like YYYYMMDDTHHMM, that is, '20041215T1530'. The add/4 solvable will naturally look the same, only adding an end time as the fourth argument.

As mentioned earlier the addEvent solvable is not used yet. This will be used when the application only will handle events in a calendar. This solvable will differ slightly from the add solvable. The type needed here is what kind of event it is. That is, meeting, birthday, appointment and so forth. The summary is the same as before, just a reminder for the user what he is supposed to do. As last argument a location of the event is required. The biggest difference will be the time representation. The representation used here will be like the prolog predicate datime/6, datime(YYYY,MM,DD,HH,MM,SS).

Since it uses a database like structure, the user is able to search for entries. The search method is so far rather simple, using the built-in unification when using OAA. The entry/1 solvable is used to search the database. As argument the user must provide what he is looking for. If the user is is looking for all entries in the database, he uses the all entries'' search, entry(X). The user can also search for all events or todos in the same way with a method call like entry(event(Summary,Id,StartDate,EndDate)). Since the database uses unification, all entries that are an event will be returned. Naturally when using unification the user can provide more information if he wants specific entries. The search entry(todo(_,_,'20041215T123000')) is searching for all todos that are to start 12:30 the 15th of December, 2004.

In addition to adding entries, the user is also able to delete entries from the database. This is a very simple delete function using the delete(X) solvable where X is the ID number of the entry to delete. The ID number is shown when the user is searching for an entry. For example, if the user makes the query entry(todo(Summary,ID,'20041215T123000')), he will get an answer like entry(todo('summary here',id(3),'20041215T123000')).

The buildCal(CalendarFileName) solvable is rather straight forward. When calling this solvable the user must give string representing the name of the *.ics file. The application will convert the database entries to text strings, writing them to the file.

The last solvable is buildDb(ExistingCalendarFileName). This is used when the user want so update his existing calendar files. The user must give the name of an existing file. The application parses the calendar file, making a database of with corresponding entries. Then the user is free to update his calendar and, perhaps, building a new calendar file.

How to start the agent

Extract the icalAgent.tar file and it should be enough to get started.

How to start the wrapper with the following call:

java -cp calendar_agent.jar:ical4j.jar:$CLASSPATH FindAgent

It is assumed that the $CLASSPATH variable contains paths to all jar files necessary for running OAA and so forth. The ical4j.jar file must be in the same directory you start the program, or be in a correct path.

If you want to handle test some files, there are some calendar files in the 'icsFiles' directory.

Test run examples

Starts with building a database from an existing file:

• oaa_Solve(buildDb('test.ics'), [])

Checks all entries. The result is displayed (now) in the debugger window:

• oaa_Solve(entry(X), [])

If the user wants to see all todos:

• oaa_Solve(entry(todo(_,_,_)), [])

The user wants to see all event starting a certain time:

• oaa_Solve(entry(event(_,_,startdate('20041215T153000'),_)), [])

Adding a new TODO to the database:

• oaa_Solve(add(todo,'testing todo','20041215T153000'), [])

Building a calendar file from the existing database:

• oaa_Solve(buildCal('test2.ics'), [])

Deleting an entry, with ID no 2, from the database:

• oaa_Solve(delete(2), [])