# frozen_string_literal: true require 'rails_helper' describe EmailMxValidator do describe '#validate' do let(:user) { instance_double(User, email: 'foo@example.com', sign_up_ip: '1.2.3.4', errors: instance_double(ActiveModel::Errors, add: nil)) } let(:resolv_dns_double) { instance_double(Resolv::DNS) } context 'with an e-mail domain that is explicitly allowed' do around do |block| tmp = Rails.configuration.x.email_domains_allowlist Rails.configuration.x.email_domains_allowlist = 'example.com' block.call Rails.configuration.x.email_domains_allowlist = tmp end it 'does not add errors if there are no DNS records' do configure_resolver('example.com') subject.validate(user) expect(user.errors).to_not have_received(:add) end end it 'adds no error if there are DNS records for the e-mail domain' do configure_resolver('example.com', a: resolv_double_a('192.0.2.42')) subject.validate(user) expect(user.errors).to_not have_received(:add) end it 'adds an error if the TagManager fails to normalize domain' do double = instance_double(TagManager) allow(TagManager).to receive(:instance).and_return(double) allow(double).to receive(:normalize_domain).with('example.com').and_raise(Addressable::URI::InvalidURIError) user = instance_double(User, email: 'foo@example.com', errors: instance_double(ActiveModel::Errors, add: nil)) subject.validate(user) expect(user.errors).to have_received(:add) end it 'adds an error if the domain email portion is blank' do user = instance_double(User, email: 'foo@', errors: instance_double(ActiveModel::Errors, add: nil)) subject.validate(user) expect(user.errors).to have_received(:add) end it 'adds an error if the email domain name contains empty labels' do configure_resolver('example..com', a: resolv_double_a('192.0.2.42')) user = instance_double(User, email: 'foo@example..com', sign_up_ip: '1.2.3.4', errors: instance_double(ActiveModel::Errors, add: nil)) subject.validate(user) expect(user.errors).to have_received(:add) end it 'adds an error if there are no DNS records for the e-mail domain' do configure_resolver('example.com') subject.validate(user) expect(user.errors).to have_received(:add) end it 'adds an error if a MX record does not lead to an IP' do configure_resolver('example.com', mx: resolv_double_mx('mail.example.com')) configure_resolver('mail.example.com') subject.validate(user) expect(user.errors).to have_received(:add) end it 'adds an error if the MX record has an email domain block' do EmailDomainBlock.create!(domain: 'mail.example.com') configure_resolver( 'example.com', mx: resolv_double_mx('mail.example.com') ) configure_resolver( 'mail.example.com', a: instance_double(Resolv::DNS::Resource::IN::A, address: '2.3.4.5'), aaaa: instance_double(Resolv::DNS::Resource::IN::AAAA, address: 'fd00::2') ) subject.validate(user) expect(user.errors).to have_received(:add) end end def configure_resolver(domain, options = {}) allow(resolv_dns_double) .to receive(:getresources) .with(domain, Resolv::DNS::Resource::IN::MX) .and_return(Array(options[:mx])) allow(resolv_dns_double) .to receive(:getresources) .with(domain, Resolv::DNS::Resource::IN::A) .and_return(Array(options[:a])) allow(resolv_dns_double) .to receive(:getresources) .with(domain, Resolv::DNS::Resource::IN::AAAA) .and_return(Array(options[:aaaa])) allow(resolv_dns_double) .to receive(:timeouts=) .and_return(nil) allow(Resolv::DNS) .to receive(:open) .and_yield(resolv_dns_double) end def resolv_double_mx(domain) instance_double(Resolv::DNS::Resource::MX, exchange: domain) end def resolv_double_a(domain) Resolv::DNS::Resource::IN::A.new(domain) end end