wanderwort

Because programming really sucks on german keyboards I ordered the international / english one this time. Despite the advancement in general hacking I really like to write some german texts without going through ‘press-key-for-10-seconds-while-holding-that-other-key’ mess.

That was the reason for writing this Layout using Ukelele.

Find it within the according Github Gist

(more…)

Keeping track of postgres activity in real-time is easy:

Postgres automatically tries to fetch it’s password from different sources:

Either save your password in an environment variable (which might be security issue)

$ export PGPASSWORD=#your-psql-password#

2. Or save it in ~/.pgpass

And use Unix’ watch to get contents from pg_stat_activity every 2 seconds:

$ watch "echo \"SELECT * FROM pg_stat_activity;\" | psql #your-database#"

Done. (Thanks Lee!)

One might want to set up dynamic attachment dimensions (or other styles) when generating images with thoughtbot’s paperclip. Styles in paperclip are basically represented in the :styles hash of has_attached_file:

class File
  has_attached_file(
    :attachment,
    :styles => { :thumb => "100x100" }
  )
end

Building a related size model in rails might look the following:

class File < ActiveRecord::Base
  has_many :sizes, :class_name => "FileSize", :dependent => :destroy
 
  has_attached_file(
    :attachment,
    :styles => # styles through FileSize model
  )
 
  def styles
   self.sizes.inject({ :thumb => "100x100" }) do |sizes, size|
      sizes[:"#{size.id}"] = "#{size.width}x#{size.height}"; sizes
    end
  end
end
 
class FileSize < ActiveRecord::Base
  belongs_to :file
end

Using a Proc we can fetch sizes from our FileSize model:

  has_attached_file(
    :attachment,
    :styles => Proc.new { |clip| clip.instance.styles }
  )

Clip is the Paperclip instance which holds an instance-method to get back to the calling Class.

As a last issue one might want to reprocess / regenerated images after creating or destroying sizes:

class FileSize < ActiveRecord::Base
  belongs_to :file
 
  after_create  :reprocess
  after_destroy :reprocess
 
  private
 
  def reprocess
    self.file.attachment.reprocess!
  end
end