diff options
Diffstat (limited to 'spec/lib/gitlab/git/storage/circuit_breaker_spec.rb')
-rw-r--r-- | spec/lib/gitlab/git/storage/circuit_breaker_spec.rb | 329 |
1 files changed, 329 insertions, 0 deletions
diff --git a/spec/lib/gitlab/git/storage/circuit_breaker_spec.rb b/spec/lib/gitlab/git/storage/circuit_breaker_spec.rb new file mode 100644 index 00000000000..c86353abb7c --- /dev/null +++ b/spec/lib/gitlab/git/storage/circuit_breaker_spec.rb @@ -0,0 +1,329 @@ +require 'spec_helper' + +describe Gitlab::Git::Storage::CircuitBreaker, clean_gitlab_redis_shared_state: true, broken_storage: true do + let(:storage_name) { 'default' } + let(:circuit_breaker) { described_class.new(storage_name) } + let(:hostname) { Gitlab::Environment.hostname } + let(:cache_key) { "storage_accessible:#{storage_name}:#{hostname}" } + + before do + # Override test-settings for the circuitbreaker with something more realistic + # for these specs. + stub_storage_settings('default' => { + 'path' => TestEnv.repos_path, + 'failure_count_threshold' => 10, + 'failure_wait_time' => 30, + 'failure_reset_time' => 1800, + 'storage_timeout' => 5 + }, + 'broken' => { + 'path' => 'tmp/tests/non-existent-repositories', + 'failure_count_threshold' => 10, + 'failure_wait_time' => 30, + 'failure_reset_time' => 1800, + 'storage_timeout' => 5 + } + ) + end + + def value_from_redis(name) + Gitlab::Git::Storage.redis.with do |redis| + redis.hmget(cache_key, name) + end.first + end + + def set_in_redis(name, value) + Gitlab::Git::Storage.redis.with do |redis| + redis.hmset(cache_key, name, value) + end.first + end + + describe '.reset_all!' do + it 'clears all entries form redis' do + set_in_redis(:failure_count, 10) + + described_class.reset_all! + + key_exists = Gitlab::Git::Storage.redis.with { |redis| redis.exists(cache_key) } + + expect(key_exists).to be_falsey + end + end + + describe '.for_storage' do + it 'only builds a single circuitbreaker per storage' do + expect(described_class).to receive(:new).once.and_call_original + + breaker = described_class.for_storage('default') + + expect(breaker).to be_a(described_class) + expect(described_class.for_storage('default')).to eq(breaker) + end + end + + describe '#initialize' do + it 'assigns the settings' do + expect(circuit_breaker.hostname).to eq(hostname) + expect(circuit_breaker.storage).to eq('default') + expect(circuit_breaker.storage_path).to eq(TestEnv.repos_path) + expect(circuit_breaker.failure_count_threshold).to eq(10) + expect(circuit_breaker.failure_wait_time).to eq(30) + expect(circuit_breaker.failure_reset_time).to eq(1800) + expect(circuit_breaker.storage_timeout).to eq(5) + end + end + + describe '#perform' do + it 'raises an exception with retry time when the circuit is open' do + allow(circuit_breaker).to receive(:circuit_broken?).and_return(true) + + expect { |b| circuit_breaker.perform(&b) } + .to raise_error(Gitlab::Git::Storage::CircuitOpen) + end + + it 'yields the block' do + expect { |b| circuit_breaker.perform(&b) } + .to yield_control + end + + it 'checks if the storage is available' do + expect(circuit_breaker).to receive(:check_storage_accessible!) + + circuit_breaker.perform { 'hello world' } + end + + it 'returns the value of the block' do + result = circuit_breaker.perform { 'return value' } + + expect(result).to eq('return value') + end + + it 'raises possible errors' do + expect { circuit_breaker.perform { raise Rugged::OSError.new('Broken') } } + .to raise_error(Rugged::OSError) + end + + context 'with the feature disabled' do + it 'returns the block without checking accessibility' do + stub_feature_flags(git_storage_circuit_breaker: false) + + expect(circuit_breaker).not_to receive(:circuit_broken?) + + result = circuit_breaker.perform { 'hello' } + + expect(result).to eq('hello') + end + end + end + + describe '#circuit_broken?' do + it 'is working when there is no last failure' do + set_in_redis(:last_failure, nil) + set_in_redis(:failure_count, 0) + + expect(circuit_breaker.circuit_broken?).to be_falsey + end + + it 'is broken when there was a recent failure' do + Timecop.freeze do + set_in_redis(:last_failure, 1.second.ago.to_f) + set_in_redis(:failure_count, 1) + + expect(circuit_breaker.circuit_broken?).to be_truthy + end + end + + it 'is broken when there are too many failures' do + set_in_redis(:last_failure, 1.day.ago.to_f) + set_in_redis(:failure_count, 200) + + expect(circuit_breaker.circuit_broken?).to be_truthy + end + + context 'the `failure_wait_time` is set to 0' do + before do + stub_storage_settings('default' => { + 'failure_wait_time' => 0, + 'path' => TestEnv.repos_path + }) + end + + it 'is working even when there is a recent failure' do + Timecop.freeze do + set_in_redis(:last_failure, 0.seconds.ago.to_f) + set_in_redis(:failure_count, 1) + + expect(circuit_breaker.circuit_broken?).to be_falsey + end + end + end + end + + describe "storage_available?" do + context 'the storage is available' do + it 'tracks that the storage was accessible an raises the error' do + expect(circuit_breaker).to receive(:track_storage_accessible) + + circuit_breaker.storage_available? + end + + it 'only performs the check once' do + expect(Gitlab::Git::Storage::ForkedStorageCheck) + .to receive(:storage_available?).once.and_call_original + + 2.times { circuit_breaker.storage_available? } + end + end + + context 'storage is not available' do + let(:storage_name) { 'broken' } + + it 'tracks that the storage was inaccessible' do + expect(circuit_breaker).to receive(:track_storage_inaccessible) + + circuit_breaker.storage_available? + end + end + end + + describe '#check_storage_accessible!' do + it 'raises an exception with retry time when the circuit is open' do + allow(circuit_breaker).to receive(:circuit_broken?).and_return(true) + + expect { circuit_breaker.check_storage_accessible! } + .to raise_error do |exception| + expect(exception).to be_kind_of(Gitlab::Git::Storage::CircuitOpen) + expect(exception.retry_after).to eq(30) + end + end + + context 'the storage is not available' do + let(:storage_name) { 'broken' } + + it 'raises an error' do + expect(circuit_breaker).to receive(:track_storage_inaccessible) + + expect { circuit_breaker.check_storage_accessible! } + .to raise_error do |exception| + expect(exception).to be_kind_of(Gitlab::Git::Storage::Inaccessible) + expect(exception.retry_after).to eq(30) + end + end + end + end + + describe '#track_storage_inaccessible' do + around do |example| + Timecop.freeze { example.run } + end + + it 'records the failure time in redis' do + circuit_breaker.track_storage_inaccessible + + failure_time = value_from_redis(:last_failure) + + expect(Time.at(failure_time.to_i)).to be_within(1.second).of(Time.now) + end + + it 'sets the failure time on the breaker without reloading' do + circuit_breaker.track_storage_inaccessible + + expect(circuit_breaker).not_to receive(:get_failure_info) + expect(circuit_breaker.last_failure).to eq(Time.now) + end + + it 'increments the failure count in redis' do + set_in_redis(:failure_count, 10) + + circuit_breaker.track_storage_inaccessible + + expect(value_from_redis(:failure_count).to_i).to be(11) + end + + it 'increments the failure count on the breaker without reloading' do + set_in_redis(:failure_count, 10) + + circuit_breaker.track_storage_inaccessible + + expect(circuit_breaker).not_to receive(:get_failure_info) + expect(circuit_breaker.failure_count).to eq(11) + end + end + + describe '#track_storage_accessible' do + it 'sets the failure count to zero in redis' do + set_in_redis(:failure_count, 10) + + circuit_breaker.track_storage_accessible + + expect(value_from_redis(:failure_count).to_i).to be(0) + end + + it 'sets the failure count to zero on the breaker without reloading' do + set_in_redis(:failure_count, 10) + + circuit_breaker.track_storage_accessible + + expect(circuit_breaker).not_to receive(:get_failure_info) + expect(circuit_breaker.failure_count).to eq(0) + end + + it 'removes the last failure time from redis' do + set_in_redis(:last_failure, Time.now.to_i) + + circuit_breaker.track_storage_accessible + + expect(circuit_breaker).not_to receive(:get_failure_info) + expect(circuit_breaker.last_failure).to be_nil + end + + it 'removes the last failure time from the breaker without reloading' do + set_in_redis(:last_failure, Time.now.to_i) + + circuit_breaker.track_storage_accessible + + expect(value_from_redis(:last_failure)).to be_empty + end + + it 'wont connect to redis when there are no failures' do + expect(Gitlab::Git::Storage.redis).to receive(:with).once + .and_call_original + expect(circuit_breaker).to receive(:track_storage_accessible) + .and_call_original + + circuit_breaker.track_storage_accessible + end + end + + describe '#no_failures?' do + it 'is false when a failure was tracked' do + set_in_redis(:last_failure, Time.now.to_i) + set_in_redis(:failure_count, 1) + + expect(circuit_breaker.no_failures?).to be_falsey + end + end + + describe '#last_failure' do + it 'returns the last failure time' do + time = Time.parse("2017-05-26 17:52:30") + set_in_redis(:last_failure, time.to_i) + + expect(circuit_breaker.last_failure).to eq(time) + end + end + + describe '#failure_count' do + it 'returns the failure count' do + set_in_redis(:failure_count, 7) + + expect(circuit_breaker.failure_count).to eq(7) + end + end + + describe '#cache_key' do + it 'includes storage and host' do + expect(circuit_breaker.cache_key).to eq(cache_key) + end + end +end |