“...I've been working since 2008 with Ruby / Ruby on Rails, love a bit of Elixir / Phoenix and learning Rust. I also poke through other people's code and make PRs for OpenSource Ruby projects that sometimes make it. Currently working for InPay...”

Rob Lacey (contact@robl.me)
Senior Software Engineer, Brighton, UK

TMail and spam filtering

I’ve been musing over the past day or so on how best to assess whether our mailers are sending out messages that are likely to get caught by over zealous spam filters and render our e-mail campaigns useless.

One possible is to run all outbound e-mails through spam assassin, so for standard mailers we can just add a spec to check the content and for form mailers we can use it during validation before the final send off.

class TMail::Mail

  def spam?
    spam_filtered_body = %x[ echo '#{self.encoded}' | /usr/bin/spamassassin ]
    return !! spam_filtered_body.match(/X-Spam-Status:\sYes/)
  end

end

new blog, RedCloth and CodeRay

I’ve decided to go back to writing my own blog software. Simply Mephisto is too much for my needs and playing around with building my own Mephisto plugin just to create a plain old boring static page is just too time consuming. In fact I was able to knock up a new blog in less time.

My main issue with writing my own blog the last time was getting RedCloth to play nicely with CodeRay. Fortunately I stumbled upon the solution on GitHub.

http://github.com/leethal/redcloth-with-coderay/tree/master

It wasn’t quite what I wanted but gave me a good start and a few modifications later we have.

“./config/initializers/redcloth_with_coderay.rb”

module RedclothWithCoderay
  
  SOURCE_TAG_REGEXP = /(<pre><code>(.+?)<\/source>)/m

  # The RedCloth extension that performs the syntax highlighting.
  def refs_syntax_highlighter(text)
    text.gsub!(SOURCE_TAG_REGEXP) do |m|
  
      all_of_it = $~[0]
      lang = ($~[2] || :ruby).to_sym
      code = $~[3].strip

      highlighted = CodeRay.scan(code, lang).html(:wrap => :div, :css => :class, :line_numbers => :inline)

      "<notextile>#{highlighted}</notextile>"
    end
  end

end

RedCloth.class_eval { include RedclothWithCoderay }

“./app/helpers/application_helper.rb”

module ApplicationHelper
  def textilize(text)
    RedCloth.new(text).to_html(:textile, :refs_syntax_highlighter)
  end
end

Typically after getting this to work adding text after any code block was susequently hampered by a bug in RedCloth-4.1.9 which had me stumped for a whole day. I have reverted to RedCloth-4.1.1 in the meantime and its all lovely again.

http://jgarber.lighthouseapp.com/projects/13054/tickets/119-notextile-blocks-included-in-following-paragrap

So woo, it works and there be joy abound. Now to import all my old blog entries and fiddle with the code highlighting to make them work super great.

Accessing TMail::Mail headers

While trying to test TMail::Mail#to header, despite setting the address in full with the recipients name I kept getting just the address back

>> t = TMail::Mail.new
=> #<TMail::Mail port=#<TMail::StringPort:id=0x3ff92369be30> bodyport=nil>
>> t.to = "RobL <someaddress@robl.me>"
=> "RobL <someaddress@robl.me>"
>> t.to
=> ["someaddress@robl.me"]

It seems there are a few ways of grabbing the to address back, to just returns an array of e-mail addresses. to_addrs or [‘to’] actually return the full “to” address.

>> t.to_addrs
=> [#<TMail::Address contact@robl.me>
>> t.to_addrs.first.to_s
=> "RobL <someaddress@robl.me>"
>> t['to'].first.to_s
=> "RobL <someaddress@robl.me>"

ActiveRecord Connection Pool

We’ve been having this irritating problem appearing intermitantly on ferret based searches.

A ActiveRecord::ConnectionTimeoutError occurred in users#search:

  could not obtain a database connection within 5 seconds.  The max pool size is currently 5; consider increasing it.
  (druby:/localhost:9010) /usr/local/lib/ruby/gems/1.8/gems/activerecord-2.2.2/lib/active_record/connection_adapters/abstract/connection_pool.rb:198:in `checkout'

We have 8 mongrels running, so ideally we’ll need at least one connection to the database per mongrel. Since we could conceivably have 8 concurrent connections to the site. You can up the connection pool size by adding the pool connection option to database.yml. A quick check in the console will demonstrate that it is now set

rl@bloodandguts:~/myapp$ ./script/console 
Loading development environment (Rails 2.2.2)
>> ActiveRecord::Base.connection.instance_variable_get(:@config)
=> {:socket=>nil, :username=>"root", :adapter=>"mysql", :host=>"127.0.0.1", :database=>"e_learning_resource_production", :password=>nil, :pool=>8}

However, the problem persisted. I wasn’t aware that ferret itself maintains its own connection to the database so I’ll likely need to change this to 9. In fact we also have backgroundrb running which will also use its own connection. I think the lesson is to account for all the different processes that may be connecting the database at once when setting this option.

development:
  adapter: mysql
  database: blah_development
  username: blah
  password: blah
  host: localhost
  socket: /var/run/mysqld/mysqld.sock
  pool: 8