Kobby GSoC: Connections and Browsing support
Its been a couple weeks since I last blogged about Kobby, and much has happened since then. In my last post I was having issues implementing a Qt socket event plugin for libinfinity, but thanks to some advice from Armin Burgmeier I was able to get this working very quickly. Since then, I have created and then added some features to the Connection Manager for Kobby to make it a little more user friendly (see below)
After getting this worked out I started on the next big step, browsing support in libinfinitymm, which not only includes traversing the directory tree of the Infinote server, but also creating and removing nodes. While looking through the infinote repository I noticed an awesome test application which creates a sort of interactive shell with the server using the client library, so I decided a great way to go about testing my C++ bindings for the Client Browser portion of libinfinity would be to replicate this test, which I just completed this afternoon. Hopefully, I will be able to implement a GUI for this by monday (meaning more screenshots) now that all the backend issues seem to be out of the way.
GSoC Phase 2: Kobby Development
After over a month of working on a C++ wrapper for the infinote libraries I was finally able to start development of the collaborative editing KTextEditor plugin this week. Its amazing what getting to see some of your development work in action, no matter how little, can do for inspiration. This week I plan on completing the session management interface and all its appendages (join session dialog, create session dialog, etc…) and hopefully will have functionality for users to connect to infinote servers by the weeks end. For those of you wondering what I’m referring to by session management: The infinote libraries allow for a set of documents, which comprise a session, to be hosted on a server and be collaboratively edited simultaneously. The Kobby session manager will allow users to join any number of sessions, keeping track of the documents in each editing session and opening/closing them when joining/leaving an infinote session. This brings up some design issues: Because a session could have a large number of documents, downloading and opening all the documents upon joining a session doesn’t seem like a good idea. The options I see are (a) creating a document management interface to select documents to open off the infinote server or (b) having a lazy-opening implementation where documents on the server are added to the editing session, but are not pulled off the server until they are actually selected by the user (anyone know for sure if this is possible?). For now, I’m going to take the document manager interface route, but the lazy implementation sounds like a tempting project, maybe worthy of an option in the configuration interface.
Introducing libinfinitymm
Now that exams are over I have been able to spend the past week getting to really work on my GSOC project. In this time I created a c++ wrapper for libinfnity, which is the library my project will be using. The git repository can be found on Gitorious. Libinfinity has a very flexible object oriented design (the online docs are AWOL, so heres my copy), and should make the rest of my project pretty straightforward. In order to implement the collaborative editing component you need to just supply an object which implements InfTextBuffer (now Infinity::TextBuffer), so making a Kate Document implement this interface should be a breeze compared to the glib/gmmproc funk I’ve been dealing with the past week. For the rest of the week I have a fair amount of testing/code scrubbing to get done, but hopefully not long after i’ll have some results to show off 
Now, back to coding.
Wrapping libinfinity
This week I have been working on creating a C++ wrapper for libinfinity. The library uses a gobject API and is very extensible, so ditching it in favor of a non-glib library would be a real waste. Luckily, there are tools like gmmproc (an internal glibmm tool) which auto-generates the C++ classes to wrap gobject based libraries, given that you don’t mind using the gtkmm source code as your documentation. Aside from having a fun time dissecting various libraries to figure out how to use gmmproc, the application is absolutely awesome. The tool reads from definition files (which can also be auto-generated from other glibmm/pygtk tools) which store data on the library’s object names, their member functions, parameters, etc. and parses .hg and .ccg files which contain C++ code with macros (such as _WRAP_METHOD) into source files which are fed to the compiler. Some documentation can be found in the gtkmm book: http://www.gtkmm.org/docs/gtkmm-2.4/docs/tutorial/html/chapter-wrapping-c-libraries.html. After getting the hang of the tool usage, wrapping the library is a breeze, so a usable version will be on its way very soon.
Kobby, Collaborative Editing
For this year’s Google Summer of Code I will be creating a KTextEditor plugin which allows for collaborative document editing. The proposal abstract can be found at http://code.google.com/soc/2008/kde/appinfo.html?csaid=9433F3446323A693.
The goal of this project is to bring in editor collaboration to KDE. This will allow users to share document trees and watch remote modifications made to them in real time. More so, in order to do this users will no longer have look outside of the editor or IDE. While I have had this project in mind it is amazing how many times I wish I had an editor with the ability to do this, mostly while sitting at a cafe trying to help out someone with a piece of code. This alone has me very excited to get this project working.
Luckily, a very powerful library for all the backend work exists, libinfinity (git://git.0×539.de/git/infinote.git). This library handles all the network communication and security, synchronization, and document hosting, while providing me with a nice TextBuffer interface to glue my plugin to. Writing this plugin will be the meat of my work this summer. Aside from that, I will be adding some nifty client-side features such as document re-visioning, and hopefully adding user access control to the library.
For now, I’m left trying to clear off my plate as much as possible before schools end so I can really devote a couple months to developing an open source project.
