discourse/app/models/screened_email.rb

83 lines
2.3 KiB
Ruby

require_dependency 'screening_model'
# A ScreenedEmail record represents an email address that is being watched,
# typically when creating a new User account. If the email of the signup form
# (or some other form) matches a ScreenedEmail record, an action can be
# performed based on the action_type.
class ScreenedEmail < ActiveRecord::Base
include ScreeningModel
default_action :block
validates :email, presence: true, uniqueness: true
before_save :downcase_email
def downcase_email
self.email = email.downcase
end
def self.block(email, opts={})
find_by_email(Email.downcase(email)) || create(opts.slice(:action_type, :ip_address).merge({email: email}))
end
def self.should_block?(email)
screened_emails = ScreenedEmail.order(created_at: :desc).limit(100)
distances = {}
screened_emails.each { |se| distances[se.email] = levenshtein(se.email.downcase, email.downcase) }
max_distance = SiteSetting.levenshtein_distance_spammer_emails
screened_email = screened_emails.select { |se| distances[se.email] <= max_distance }
.sort { |se| distances[se.email] }
.first
screened_email.record_match! if screened_email
screened_email && screened_email.action_type == actions[:block]
end
def self.levenshtein(first, second)
matrix = [(0..first.length).to_a]
(1..second.length).each do |j|
matrix << [j] + [0] * (first.length)
end
(1..second.length).each do |i|
(1..first.length).each do |j|
if first[j-1] == second[i-1]
matrix[i][j] = matrix[i-1][j-1]
else
matrix[i][j] = [
matrix[i-1][j],
matrix[i][j-1],
matrix[i-1][j-1],
].min + 1
end
end
end
return matrix.last.last
end
end
# == Schema Information
#
# Table name: screened_emails
#
# id :integer not null, primary key
# email :string(255) not null
# action_type :integer not null
# match_count :integer default(0), not null
# last_match_at :datetime
# created_at :datetime
# updated_at :datetime
# ip_address :inet
#
# Indexes
#
# index_screened_emails_on_email (email) UNIQUE
# index_screened_emails_on_last_match_at (last_match_at)
#