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What is better for optimizing the load time of pages on the iPhone: minifying or packing your javascript?

Interesting

• Selenium removes the If-Modified-Since header. This gets in your way if you are testing ETags.

• Speaking of ETags - they are awesome. See Ryan Daigle's article for code.

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Just how slow is Mongrel when serving static images?

The answer is - pretty slow. The reason for the question was that Google's crawler tends to keep a single connection open and fire lots and lots of http requests over a period of several hours. With a standard Nginx/Mongrel setup, this would tie up a mongrel for this entire period.

A proposed solution to this problem is to use HAProxy between Nginx and Mongrel.

Interesting

• With RMagick 2.9.1 and ImageMagick 6.4.6.9 (or so), you get a 1x1 pixel image if you crop and then resize an image to be bigger:

image.crop!().resize!()

• Pivotal Tracker is a finalist for a Jolt award in project management. Good luck Tracker!

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How do you make a Mac not sleep?

Use the Energy Saver section of the System Preferences.

Interesting

• RubyMine 749 is out. Many of the existing bugs have been fixed, but a few new ones have been found. Notably, running specs with a "#" character in the describe string has problems.

• The USPS has a nifty web service for addresses. The zip code lookup (which gives you zip+4) and the address standardization services were found to be useful.

Interesting

• Rails 2.2.2 is released!

• Even Rails 2.2.2 isn't always threadsafe. I found this out by running a script with JRuby from the command line. The script loaded the Rails environment and then launched two threads that simply tried to resolve an ActiveRecord class constant. Fireworks (in the form of LoadError) ensued deep inside of const_missing. I'll post the full example later today.

• Tsearch2 is now built into Postgres (as of 8.3). This means you must remove the metadata from your tables, since Postgres now stores it in a separate place.

Interesting

• Until a recent commit, Polonium defined a method on Module named deprecate, which (at least in our case) overrode the method of the same name defined in Rails. This caused some code in Rails to blow up at class loading time when trying to call Rails' deprecate method with the wrong number of arguments.

  We changed the name of Polonium's method so it wouldn't clash with Rails, and checked this into the master branch of Polonium on GitHub.

• As of Rails 2.1, ActiveRecord support partial updates, which means that it's smarter about what fields get updated in the SQL UPDATE statement issued by save. If you haven't updated any fields in the object, no update will happen at all, no AR callbacks will fire, etc. If you depend on these things to happen even when not updating any fields, you can call will_change! on the model object. It was floated that a force_save method might be helpful.

• It is often claimed that Symbol#to_proc is to slow to use in production code. But a clever Rubyist out there found a way to speed it up by 4x.

• The test run for one of our projects here runs in 223 seconds on OSX, but in in 157s on Ubuntu. We'd like to figure out why (we're pretty sure we're using the MySQL Gem rather than the built-in MySQL driver that comes with Rails)

• Git4Idea is now available through the IntelliJ Plugin manager. No more hand installation!

• ActiveRecord::Base#to_param must return a String if you override it. If you return an Integer you will get a weird "Can't convert Fixnum to String" exception somewhere deep in the routing code. You can't even tell where the exception is coming from due to the routing code's bizarreness.

Help!

• Has anybody successfully used the drag-and-drop functionality included in the newer versions of Selenium? It doesn't appear to work - the mouse events never seem to get fired.

Interesting

• If you're messing with the solr.war inside of the solr_runner plugin, beware that the webapps directory (in which it sits) is scanned by Jetty for .war files, and that when your use 'rake solr_runner:start', you might not be running off the .war file you think you are. When we started SOLR this way, we saw some output from Jetty that indicated that it was unpacking and using the wrong .war file from that directory (in our case, it apparently used solr.war.new!).

  The moral of the story is, if you want to swap in a new version of solr.war, just move it on top of the existing one, and don't put any other files in there.

Help!

• Does anybody know anything about Lucene scoring using a document boost?

  We see an exponential relationship between document boost and the fieldNorm component of the score for each term. Can anybody explain this?

Help!

• How do I turn off coloring in the RSpec runner?

  The answer: don't put

  --color

  in your spec/spec.opts file.

Interesting

• There's an easy way to merge hashes in Javascript, using either JQuery or Prototype.

  For JQuery:

  $.extend(target, hash1, hash2, ...)

  For Prototype:

  Object.extend(target, hash)

  JQuery's syntax is a bit nicer since you can merge any number of hashes into the target hash.

  This is handy for grabbing JSON off the wire and merging it into an existing or "default" object.

  You can use this to merge prototypes, achieving a type of "inheritance" (or what passes for such in Javascript). But be careful, since the rightmost hash wins - IE, its properties overide properties by the same name in the target.