Pretty code snippets for the masses

In my last blog entry I pointed out a tool called Coderay for generating syntax-highlighted html for blog posts. Two train rides later and I've launched an application that should make life a whole lot easier for folks who want pretty code on their blog.

I give you Spotlight:

http://spotlight.heroku.com/

In other news, heroku is awesome.

I can stop whining about syntax highlighting for my blog

I've been googling off and on in what turned out to be a rather futile attempt at figuring out how to get the cute syntax highlighting you see on a lot of the major rails blogs working. Via The Rails Way I discovered the feature was apparently related to Mephisto, for which I promptly downloaded the source.

A few minutes later I found what I was looking for:

http://rubyforge.org/projects/coderay/

Debugging ERB Rendering In Rails

I had a helluva time figuring out that attempting to output a scriptlet that begins a block segment causes ERB to generate bad ruby code. Here's an example:

1 <%= tag_with_body do %><%end%>

What I really needed was a way to dump the generated ruby code from ERB. Turns out you can. On the last line of my controller action I added the following:

1 puts @__erbout

will_paginate remotely

I've patched the awesome will_paginate plugin from Mislav Marohnic to support rails' link_to_remote helper. Now you can easily tell will_paginate that it should update an element in the DOM instead of doing a full request cycle:

1 <%= will_paginate @pages, :update => "story_box", :params=> {}%>

I submitted a patch to Mislav, but I can't tell you when or if it'll get into the official release. For the more adventurous hackers out there here's a messier but more concise version of the patched code:

monkeypatch the page_link_or_span method in will_paginate/lib/will_paginate/view_helpers.rb:

 1 def page_link_or_span(page, span_class = 'current', text = nil)
 2   text ||= page.to_s
 3   if page and page != current_page
 4     if update = @options[:update]
 5       @template.link_to_remote text, :update => update, :url =>    url_options(page)
 6     else
 7       @template.link_to text, url_options(page)
 8     end
 9   else
10     @template.content_tag :span, text, :class => span_class
11   end
12 end

Spring IOC in JRuby - life outside the container

If you're a JRuby aficionado you probably read about the Spring IOC Plugin for rails, but what if you want to get spring IOC running outside a servlet container? Here's how.

Now, the first important thing I learned is that spring uses the Java Thread's context class loader to load its resources. If you're using JRuby's $CLASSPATH to set up your test environment this poses a problem. So, first thing I override the current Thread's context class loader at the end of my test.rb environment file:

require 'java'
require 'jruby'

java.lang.Thread.current_thread.context_class_loader = JRuby.runtime.getJRubyClassLoader

Now we can move on to Spring. We can't use the WebApplicationContext that the Spring plugin uses because it'll (obviously) complain that there isn't a servlet context. So let's fall back on the ClassPathXmlApplicationContext. Add this wherever you'd like to hook in and replace the spring context from the plugin:

config = ["classpath:applicationContext.xml",
          "classpath:applicationContext-service.xml"]
ctx = ClassPathXmlApplicationContext.new(config.to_java(:string))

And there you go! Provided you've configured the $CLASSPATH correctly you should be on your way.