Building with Rake (Jim Weirich)

I did manage to squeeze in a single slide showing the creating of a GEM file from a GemSpec. This was a teaser from the RubyGem folk that Rich elaborated on later in his talk.

Toward a Refactoring Framework for FreeRide (Hal Fulton)

Hal shared some of his ideas for a Refactoring framework for FreeRide. He has been experimenting with the Scientilla editor widget and has some (very) rudimentary refactoring and code assists running. Truthfully, Hal was limited by the lack of a good Ruby-based parser for Ruby. Without that, a full featured rectoring browser will have to wait.

The discussion that followed Hal’s talk centered on the need for a good Ruby parser. There was some talk about Ripper, which is a port of the original parse.y file from the Ruby source base, but replaces explicit parse actions with a callback/event based mechanism to allow something other than the Ruby interpreter to use it. FreeRide is using this parser and there is some hope that it will be integrated back into the Ruby source tree so there will be only one parser. I can think of serveral projects that would benefit from this.

Ruby and the Java Debug Wire Protocol (Rich Kilmer)

I don’t think Rich could decide what topic he wanted to present at the conference this year. The main thrust of his presentation was about using Ruby to control Java VM via the Java Debug Wire Protocol. Rich uses a ruby based monitoring script to control the execution of over 100 (large) JVMs.

One thing that I found particularly interesting was how Rich generated the code for the low level debug packets. The JDWP is a binary protocol, with around 70 different packet types. There is an HTML writeup from SUM detailing all these different packet types. Rich transformed (by hand) the descriptions of the packets in HTML to more or less isomorphic Ruby code. In other words, He described the packets using Ruby instead of HTML. He then wrote a generated that loaded the Ruby descriptions of the packets and generated code to parse, send and receive the packets. The Ruby description and generator were several hundred lines of code, but the final generated code base was well over 1500 lines. Not a bad trade-off.

I’ve been thinking about Ruby as a declarative language for a bit. See onestepback.org/articles/buildingwithrake/appa.html for some of my thoughts in the area.

When Rich got to the demo portion of his talk, he pulled up a terminal window and tried to run his program which immediately failed because one of the Ruby JDWP libraries were not installed. "Oh look" says Rich in a mock serious voice, "I’ve got a GEM for that library here." Rich runs the GEM which installs the library. He then tries the demo again, but it fails because it is requiring the wrong version of the library. Rich fixes the version problem and the demo runs without a hitch.

What you missed if you blinked was that Rich inserted a mini-demo of the RubyGems project into the middle of his Ruby-JDWP demo. Although sneaky, the next part of the demo should he had even more tricks up his sleeve.

The demo consited of a JVM running some Java-2D demos and a GUI listing the JVM threads and command buttons to start and stop individual threads or the entire JVM. The GUI was implemented by Ruby code, and although I couldn’t place the toolkit used to generate it, I didn’t really think too much about it.

After the demo, Rich revealed that the GUI was done using the Alph project (Rich had been dropping hints about Alph all weekend long). The GUI was drawn in a Flash component and communicated with a controlling Ruby script that specified the components and buttons to appear on the page and then handled the callbacks when those buttons were clicked. The Flash portion of the GUI is a single file that implements all the components, but lets the Ruby script completely control it. You need the proprietary MacroMedia development kit to create that Flash file, but once created it can be used by any Ruby script. In other words, you can develope your GUI completely in Flash without using the proprietary Flash development kit. Cool!

Why is it named Alph? It comes from the poem:

  In Xanadu, did Kubla Khan
  A stately pleasure dome decree
  Where Alph the sacred river, ran
  Through caverns measureless to man
  Down to a sunless sea.

Rich was thinking of a GUI Utopia, and Alph the river runs right through that utopia. One of my favorite quotes from Rich during the talk:

"This is pretty much the fun thing you do in Open Source, is think of names." — Rich Kilmer

Post Conference Activities

The presentation portion of the conference ended around 11:30. Lunch was to be served at noon, so I hustled up to my room to check out of the hotel. After lunch, several of us decided to head to the airport to take advantage of the WIFI network, even though our flights were not scheduled for several hours.

At the airport, Chad and Rich put some final touches on the RubyGems code and checked it into RubyForge CVS tree. I did some cleanup on Rake and as soon as they check RubyGems in, I updated the copy on my laptop and generated a GEM for Rake 0.2.9. I then uploaded the GEM to the file area of RubyForge allowing me to claim the first GEM enabled application on RubyForge (we are ignoring for the moment that I forgot to use a "require_gem" in the source, so the fact that the Rake GEM won’t work out of the box is a small blight on that claim).

Rich and Chad’s flight was about a half an hour before mine, so after they left I hung around the ruby-lang IRC channel and answered some questions on RubyGems. I even started the gem_server on my laptop and allowed a couple people to download the Rake GEM directly through the gem_server before I to pack up to make a plane. What a great way to cap off the whole weekend.

Late Update: Presentation Source

Ryan Davis is hosting all the 2003 RubyConf presentations. You can find them at www.zenspider.com/Languages/Ruby/RubyConf2003.html