postal/app/models/track_certificate.rb

# == Schema Information
#
# Table name: track_certificates
#
#  id                  :integer          not null, primary key
#  domain              :string(255)
#  certificate         :text(65535)
#  intermediaries      :text(65535)
#  key                 :text(65535)
#  expires_at          :datetime
#  renew_after         :datetime
#  verification_path   :string(255)
#  verification_string :string(255)
#  created_at          :datetime         not null
#  updated_at          :datetime         not null
#
# Indexes
#
#  index_track_certificates_on_domain  (domain)
#

class TrackCertificate < ApplicationRecord

  validates :domain, :presence => true, :uniqueness => true

  default_value :key, -> { OpenSSL::PKey::RSA.new(2048).to_s }

  scope :active, -> { where("certificate IS NOT NULL AND expires_at > ?", Time.now) }

  def active?
    certificate.present?
  end

  def get
    verify && issue
  end

  def verify
    authorization = Postal::LetsEncrypt.client.authorize(:domain => self.domain)
    challenge = authorization.http01
    self.verification_path = challenge.filename
    self.verification_string = challenge.file_content
    self.save!
    challenge.request_verification
    checks = 0
    until challenge.verify_status != "pending"
      checks += 1
      return false if checks > 30
      sleep 1
    end

    unless challenge.verify_status == "valid"
      return false
    end

    return true
  rescue Acme::Client::Error => e
    @retries = 0
    if e.is_a?(Acme::Client::Error::BadNonce) && @retries < 5
      @retries += 1
      sleep 1
      verify
    else
      return false
    end
  end

  def issue
    csr = OpenSSL::X509::Request.new
    csr.subject = OpenSSL::X509::Name.new([['CN', self.domain, OpenSSL::ASN1::UTF8STRING]])
    private_key = OpenSSL::PKey::RSA.new(self.key)
    csr.public_key = private_key.public_key
    csr.sign(private_key, OpenSSL::Digest::SHA256.new)
    https_cert = Postal::LetsEncrypt.client.new_certificate(csr)
    self.certificate = https_cert.to_pem
    self.intermediaries = https_cert.chain_to_pem
    self.expires_at = https_cert.x509.not_after
    self.renew_after = (self.expires_at - 1.month) + rand(10).days
    self.save!
    return true
  end

  def certificate_object
    @certificate_object ||= OpenSSL::X509::Certificate.new(self.certificate)
  end

  def intermediaries_array
    @intermediaries_array ||= self.intermediaries.to_s.scan(/-----BEGIN CERTIFICATE-----.+?-----END CERTIFICATE-----/m).map{|c| OpenSSL::X509::Certificate.new(c)}
  end

  def key_object
    @key_object ||= OpenSSL::PKey::RSA.new(self.key)
  end

end