KOffice and RDF: Say it with Style...

This scattered series of posts has been about the RDF support I'm working on for KOffice. The ODF document format lets you store RDF/XML data inside the document file, which in turn lets both a human reader and a computer know about things that comprise an office document. You can refer to a person, place, or time and have the computer know what you are saying without having to resort to heuristics.

Having RDF support in document formats means you can send somebody a single file containing exact information about real world events. The RDF can contain details which can be pulled up in the formatting of the text that you see. For example, for a given contact you might know his phone number, home page, normal business location, email address etc. You might only want to see a small fraction of this information at one place in a document, but perhaps for a header you want to know the postal address too. Stylesheets are what I'm working on right now to let that happen.

At the start of the video below, you can see James, Joyce and Mark. As I click on these contacts, the RDF docker tells me information about them. As you can see, there is more information known to KOffice than is shown in the document (first & last name). However, for Mark, we also know where he is and that is shown in the RDF docker.

James is mentioned in the second paragraph, and the document is talking about giving him a call to verify something. Instead of hunting down his phone number, you can set a semantic stylesheet for that particular reference to him in the document to include is phone number inline in the document text. The added advantage here is that if you edit his phone number via the RDF docker, all the places in the document text that cite the phone number are updated for you. KOffice knows that those digits are James' phone number, so it can modify them for you.

Later on we again cite the event itself, just saying its "next weekend", which isn't an ideal description of when a specific event is happening. Luckily, we have cited the RDF event, so it shows up in the RDF docker and the stylesheets are available to reformat the text. In this case I want to see the summary and when it starts.

I'm working on adding user specified stylesheets now too, as the Format menu shows in the video. When you create a user stylesheet it is also saved in RDF, so the stylesheets you make become part of the document itself. They will be available when some other KOffice user loads the document.

The File/Document Information widget has a new RDF section which lets you see and directly edit the RDF triples if that's your thing, the semantic tab shows you all the higher level things that KOffice has seen in the document, like poeple, places, and events, and finally the stylesheets page lets you nominate how you want things formatted by default. For example, you might want to see a persons name and phone number so setting that to the default lets you then drag and drop some contacts from kaddressbook into the document and you will see the phone number as part of the document text.

Of course, you can drag and drop items from the RDF docker into kaddressbook and korganizer. These pieces of information should be able to be moved into and out of an ODF file using KOffice without thinking about it. You want to add Fred to the text, pick him up from your kaddressbook and drop him into the RDF docker. Your default contact stylesheet is then used to insert some text into the document at the current cursor location showing you the Fred contact. Quick and simple... Lets make RDF something everybody uses but nobody needs to learn about (unless they want to).

KOffice and RDF: Say it with Style... from Ben Martin on Vimeo.

KOffice & RDF: Who, What, When, Where?

As mentioned in a previous post, ODF documents can contain one or more RDF/XML files. These files allow you to unambiguously encode information for both computer and human consumption. So you can describe a person in a way that tells you their phone number and also lets the computer know that these digits are a specific person's home phone number. Common data formats like vcard and ical have some encodings in RDF and soon a KOffice near you will understand these pieces of data from ODF files.

KOffice currently understands some of the FOAF vocabulary (storing contact data), and the rdfical format (for events). There are a few ways to encode longitude and latitude in RDF. The current patch supports two of them, with optional linking to rdfical. This is one of the major strengths of RDF, you can say who, where and when and also link these things together so an event carries not only a time but its location information too.

The below video shows the new RDF docker in aciton. As you click on text that has associated RDF, the docker shows you the interesting information. Frodo and Sam are assoicated with both traditional contact data and a location. The items in the RDF docker let you import them into your system (into kaddressbook or korganizer) or export them to well known desktop formats like vcard and ical. Editing locations is done with Marble and there is only a minimal set of information for contacts and events currently. Note that mid way through when I edit an event, timezones are respected. If the RDF describes an event as being in Tokyo, that timezone offset from your current localtime is respected.

Towards the end of the video I show that contacts can be simply drag and dropped between koffice and kaddressbook. This also works for events to/from Evolution but I had some issues with korganizer for events. D&D makes KOffice and ODF quite a convenient format for transmitting semantic information to colleagues in a single, self describing file.

KOffice & RDF: Who, What, When, Where? from Ben Martin on Vimeo.