Script to add users to the ZeusWPI LDAP

add-user.rb

#!/usr/bin/ruby
# Script to add a new user in the Zeus LDAP

require 'fileutils'

# Find a new user id
#
def find_new_user_id
  id = 1200
  while not `getent passwd #{id}`.empty? do id = id + 1 end
  return id
end

# Create an ldif that can be imported intro the database
#
def create_ldif user_name, first_name, last_name, password
  return <<-EOS.gsub(/^ {4}/, "")
    version: 1

    dn: uid=#{user_name},ou=People,dc=zeus,dc=UGent,dc=be
    cn: #{first_name} #{last_name}
    gecos: #{first_name} #{last_name}
    gidnumber: 103
    givenname: #{first_name}
    homedirectory: /home/trial/#{user_name}
    loginshell: /bin/bash
    mail: #{user_name}@zeus.UGent.be
    objectclass: person
    objectclass: organizationalPerson
    objectclass: inetOrgPerson
    objectclass: posixAccount
    objectclass: top
    objectclass: shadowAccount
    shadowlastchange: 14875
    shadowmax: 99999
    shadowwarning: 7
    sn: #{last_name}
    uid: #{user_name}
    uidnumber: #{find_new_user_id}
    userpassword: #{password}
  EOS
end

# Generate a random password
#
def random_password
  chars = ("a".."z").to_a
  newpass = ""
  1.upto(6) do
    |i| newpass << chars[rand(chars.size-1)]
  end
  return newpass
end

# Create a home directory and put a .forward file in it
#
def initialize_home user_name, email
  home_dir = "/home/trial/#{user_name}"
  FileUtils::mkdir_p home_dir
  FileUtils::chown "#{user_name}", "users", home_dir
  File.open "#{home_dir}/.forward", 'w' do |file|
    file.write email
  end
end

# Add a user to the mailing list
#
def add_to_mailing_list user_name
  email = "#{user_name}@zeus.ugent.be"
  `echo "#{email}" | /var/lib/mailman/bin/add_members -w n -r - leden`
end

# Mail a user about his password
#
def send_password_mail user_name, email, password
  mail_body = <<-EOS.gsub(/^ {4}/, "")
    Uw zeus account (#{user_name}) is aangemaakt en uw wachtwoord is ingesteld
    op #{password}. Gelieve in te loggen via ssh op zeus.ugent.be, poort 2222
    en met het commando passwd uw wachtwoord te veranderen. In geval van
    problemen of vragen, mail naar jasper@zeus.ugent.be.
  EOS
  `echo '#{mail_body}' | mail -s "Uw Zeus Account" #{email}`
end

# Simple prompt
#
def prompt title
  print "#{title}: "
  gets.chop
end

# Check if a given user exists
#
def user_exists user_name
  not `id -u #{user_name} 2>/dev/null`.empty?
end

# Main function, sorta
#
def main
  # Get a username
  user_name = prompt "User name"
  if user_exists user_name then
    puts "User #{user_name} already exists."
    exit 1
  end  

  # Read simple fields
  first_name = prompt "First name"
  last_name = prompt "Last name"
  email = prompt "Email"

  # Generate a password
  password = random_password

  # Create the ldif file
  ldif = create_ldif(user_name, first_name, last_name, password)
  File.open "temp.ldif", "w" do |file|
    file.write(ldif)
  end

  # Import the ldif file, then remove it
  `ldapadd -v -x -W -D cn=root,dc=zeus,dc=ugent,dc=be -f temp.ldif`
  FileUtils::rm "temp.ldif"

  # Wait a bit
  puts "Waiting for user..."
  until user_exists user_name do sleep 1 end

  # Various administrative tasks
  initialize_home user_name, email
  add_to_mailing_list user_name
  send_password_mail user_name, email, password
end

# Run
main