Rails has come a long way quickly, but one of the biggest problems with our favorite MVC framework is support for multiple databases.

Sure you can use self.table_name and/or establish_connection to force a model to point to a table in a different db, but try running a freaking test with fixtures for the offshoot models, and you'll see what I'm talking about.

Even more depressing is SQLite3's lack of cross-database query join support, making this statement impossible:

has_and_belongs_to_many :blocked_users,
:class_name => 'User', :join_table => :blocked_users,
:foreign_key => "user_id", :association_foreign_key => "blocked_user_id"

Here's the kicker: All of our apps are multi-database apps, so that means no more SQLite allowed for us, and I really loved it until now.

If I'm wrong, let me know. I'd love to go back to using SQLite for local development. Same for an easy way to load fixtures.

I wrote a script tonight to curl several URLs, but sleep for 2 minutes in between each request. I piggybacked on a little script written by programmer John McCann from NYC. Here's what the code looks like:

#!/usr/bin/env ruby
RAILS_ROOT = File.expand_path(File.dirname(__FILE__) + '/..')

require File.join(RAILS_ROOT, "config/environment")

puts "writing curl script..."

t1 = Time.now

foos = Foo.find_by_sql("select distinct bar from foos;")

curls = foos.map! {|foo| "curl 'https://some.api.com?data=%7Bfoobar%3A#{foo.bar}%7D&key=12345'\n"}

curl_script = curls.join("sleep 120\n")

File.open("curl.sh", "w") {|f| f <<>

t2 = Time.now

puts "curl script written in " + (t2 - t1).to_s + " seconds"

What's fun about this script is that it was a new challenge for me on a couple fronts. I learned about encoding curl requests (%7Bfoobar%3A#{foo.bar}%7D produces {foobar:[value_of_foo.bar]}). After clumsily grabbing all objects and filtering after the query, I refactored the SQL to just grab distinct values from the db. I learned that the "w" attribute of the File.open class method either creates a file or sets its byte count to 0 if it already exists. And finally I learned about the "sleep" function which takes an integer parameter representing the number of seconds to wait until the next line is executed - this was especially helpful in not hammering the service I was accessing.

So not a major script, but pretty fun and interesting nonetheless.

In Conclusion,

I heart curl.