Convert from GnuCash Sqlite format to ledger/hledger format

gnucashsqlite2ledger.rb

#!/bin/env ruby
# (C) 2015 Thomas R. Koll, <info@ananasblau.com>
# Licensed under WTFPL

# In GnuCash save your file as sqlite3 and pass the filename as argument to this script
# The script only requires active_record to be installed

require 'active_record'

ActiveRecord::Base.establish_connection(
    :adapter => "sqlite3",
    :database  => ARGV[0]
)

class Account < ActiveRecord::Base
  self.primary_key = 'guid'
  has_many :splits
  belongs_to :parent, class_name: 'Account', foreign_key: 'parent_guid'
end

class Transaction < ActiveRecord::Base
  self.primary_key = 'guid'
  has_many :splits, foreign_key: 'tx_guid'
end

class Split < ActiveRecord::Base
  self.primary_key = 'guid'
  belongs_to :account, foreign_key: 'account_guid'
end

accounts = {}
Account.all.each do |account|
  next if account.parent.nil?
  name = [account.name]
  accounts[account.guid] = name
  while account.parent
    account = account.parent
    unless account.parent.nil?
      name.unshift(account.name)
    end
  end
end
accounts.each_pair{|k,v| accounts[k] = v.join(':') }

Transaction.all.to_a.each do |transaction|
  puts "%s %s" % [Date.parse(transaction.post_date).to_s("%Y/%m/%d"), transaction.description]
  transaction.splits.each do |split|
    account = accounts[split.account_guid]
    puts ("    %s    %s" % [account, split.value_num / split.value_denom.to_f]).gsub(/\.0$/, '')
  end
  puts ""
end