diff options
Diffstat (limited to 'spec/lib/gitlab/database/load_balancing/resolver_spec.rb')
-rw-r--r-- | spec/lib/gitlab/database/load_balancing/resolver_spec.rb | 80 |
1 files changed, 80 insertions, 0 deletions
diff --git a/spec/lib/gitlab/database/load_balancing/resolver_spec.rb b/spec/lib/gitlab/database/load_balancing/resolver_spec.rb new file mode 100644 index 00000000000..0051cf50255 --- /dev/null +++ b/spec/lib/gitlab/database/load_balancing/resolver_spec.rb @@ -0,0 +1,80 @@ +# frozen_string_literal: true + +require 'spec_helper' + +RSpec.describe Gitlab::Database::LoadBalancing::Resolver do + describe '#resolve' do + let(:ip_addr) { IPAddr.new('127.0.0.2') } + + context 'when nameserver is an IP' do + it 'returns an IPAddr object' do + service = described_class.new('127.0.0.2') + + expect(service.resolve).to eq(ip_addr) + end + end + + context 'when nameserver is not an IP' do + subject { described_class.new('localhost').resolve } + + it 'looks the nameserver up in the hosts file' do + allow_next_instance_of(Resolv::Hosts) do |instance| + allow(instance).to receive(:getaddress).with('localhost').and_return('127.0.0.2') + end + + expect(subject).to eq(ip_addr) + end + + context 'when nameserver is not in the hosts file' do + it 'looks the nameserver up in DNS' do + resource = double(:resource, address: ip_addr) + packet = double(:packet, answer: [resource]) + + allow_next_instance_of(Resolv::Hosts) do |instance| + allow(instance).to receive(:getaddress).with('localhost').and_raise(Resolv::ResolvError) + end + + allow(Net::DNS::Resolver).to receive(:start) + .with('localhost', Net::DNS::A) + .and_return(packet) + + expect(subject).to eq(ip_addr) + end + + context 'when nameserver is not in DNS' do + it 'raises an exception' do + allow_next_instance_of(Resolv::Hosts) do |instance| + allow(instance).to receive(:getaddress).with('localhost').and_raise(Resolv::ResolvError) + end + + allow(Net::DNS::Resolver).to receive(:start) + .with('localhost', Net::DNS::A) + .and_return(double(:packet, answer: [])) + + expect { subject }.to raise_exception( + described_class::UnresolvableNameserverError, + 'could not resolve localhost' + ) + end + end + + context 'when DNS does not respond' do + it 'raises an exception' do + allow_next_instance_of(Resolv::Hosts) do |instance| + allow(instance).to receive(:getaddress).with('localhost').and_raise(Resolv::ResolvError) + end + + allow(Net::DNS::Resolver).to receive(:start) + .with('localhost', Net::DNS::A) + .and_raise(Net::DNS::Resolver::NoResponseError) + + expect { subject }.to raise_exception( + described_class::UnresolvableNameserverError, + 'no response from DNS server(s)' + ) + end + end + end + end + end +end |