Decompose ActiveRecord script into methods

Ruby
1

If I commend out the def and end lines for the “all” method, the script
runs fine. However, the goal is to decompose the script into several
methods, which fails with:

thufir@ARRAKIS:~/projects/aggregator$
thufir@ARRAKIS:~/projects/aggregator$ ruby rss2mysql.rb
rss2mysql.rb:19: class definition in method body
thufir@ARRAKIS:~/projects/aggregator$

The script is adapted from:

Practical Ruby Gems
http://www.apress.com/book/view/9781590598115
Chapter 5

require ‘rubygems’
require ‘active_record’
require ‘feed_tools’
require ‘yaml’

def all

  db = YAML.load_file("database.yml")
ActiveRecord::Base.establish_connection(
    :adapter  => db["adapter"],
    :host   => db["host"],
    :username => db["username"],
    :password => db["password"],
    :database => db["database"])

class Items < ActiveRecord::Base
end

If the table doesn’t exist, we’ll create it.

unless Items.table_exists?
ActiveRecord::Schema.define do
create_table :items do |t|
t.column :title, :string
t.column :content, :string
t.column :source, :string
t.column :url, :string
t.column :timestamp, :timestamp
t.column :keyword_id, :integer
t.column :guid, :string
t.column :html, :string
end
end
end

feed_url = ‘Slashdot’

feed=FeedTools::Feed.open(feed_url)
feed.items.each do |feed_item|
unless (Items.find_by_title(feed_item.title)
or Items.find_by_url(feed_item.link)
or Items.find_by_guid(feed_item.guid))
puts “processing item ‘#{feed_item.title}’ - new”

Items.new do |newitem|
   newitem.title=feed_item.title.gsub(/<[^>]*>/, '')
   newitem.guid=feed_item.guid
   if feed_item.publisher.name
       newitem.source=feed_item.publisher.name
   end
   newitem.url=feed_item.link
   newitem.content=feed_item.description
   newitem.timestamp=feed_item.published
   newitem.save
end

else
puts “processing item ‘#{feed_item.title}’ - old”
end
end

end #end all

thanks,

Thufir

2

On Tue, Sep 22, 2009 at 4:45 PM, Thufir [email protected] wrote:

If I commend out the def and end lines for the “all” method, the script
runs fine. However, the goal is to decompose the script into several
methods, which fails with:

thufir@ARRAKIS:~/projects/aggregator$
thufir@ARRAKIS:~/projects/aggregator$ ruby rss2mysql.rb
rss2mysql.rb:19: class definition in method body
thufir@ARRAKIS:~/projects/aggregator$

The error message tells you exactly what is wrong:

class Items < ActiveRecord::Base
end

You can’t have a class declaration like this inside a method body.

Instead of making a single method around the whole script, make at
least 2 methods, one which covers the code before the class
declaration, then one which covers the code after it. Or move the
class definition to the top of the file, before def all.

thanks,

Thufir

–
Paul S.
http://www.nomadicfun.co.uk

[email protected]

3

On Wed, 23 Sep 2009 00:54:23 +0900, Paul S. wrote:

top of the file, before def all.
Ah, before the class, that makes sense. I suppose what I was wanting
was
to declare the class in a separate file and then “require ‘Items.rb’”,
how would that work?

thanks,

Thufir