How to make more efficient code in model? - performance

Question

Any idea to refactor the code of the method self.import_data ? It's a method which allow the application to save CSV file in database (with some restriction on the user email). It's supposed to run every day at noon so it has to be quick.
Currently its very long to run when I have a big CSV file. I wonder if there a way to make this code more efficient and win some time (or to avoiding the loop or make less request...). I don't really know what makes the process so long actually and how to correct it.
Here is my model :
class Person < ActiveRecord::Base
has_paper_trail
validates :email, uniqueness: true
require 'csv'
def is_former_email?(update_email)
self.versions.each do |version|
next if version.object.nil?
return true if version.object.include?(update_email)
end
end
def self.import_data
filename = File.join Rails.root, '/vendor/people.csv'
CSV.foreach(filename, headers: true, col_sep: ',') do |row|
firstname, lastname, home_phone_number, mobile_phone_number, email, address = row
person = Person.find_or_create_by(firstname: row["firstname"], lastname: row['lastname'], address: row['address'] )
if person.is_former_email?(row['email']) == true
puts "not allowed"
else
person.update_attributes({firstname: row['firstname'], lastname: row['lastname'], home_phone_number: row['home_phone_number'], mobile_phone_number: row['mobile_phone_number'], address: row['address'], email: row['email']})
end
end
end
end

Answer 1

I was a little refactored your code, but for more efficiently I recommend to use gem activerecord-import and optimize versions model for search previous emails.
class Person < ActiveRecord::Base
require 'csv'
FILE_NAME = File.join Rails.root, '/vendor/people.csv'
validates :email, uniqueness: true
has_paper_trail
def self.import_data
people = CSV.new(File.new(FILE_NAME), headers: true, header_converters: :symbol, converters: :all).to_a.map(&:to_hash)
versions_by_item_id = Version.where(item_type: 'Person').select('item_id, object').group_by(&:item_id)
people.each do |person_params|
person = Person.find_or_create_by(person_params.slice(:firstname, :lastname, :address))
if versions_by_item_id[person.id] && versions_by_item_id[person.id].sum { |v| v.object.to_s }.include?(person_params[:email])
puts 'not allowed'
else
person.update_attributes(person_params.slice(:home_phone_number, :mobile_phone_number, :email))
end
end
end
end