# frozen_string_literal: true require 'spec_helper' RSpec.describe Gitlab::Redis::MultiStore do using RSpec::Parameterized::TableSyntax let_it_be(:redis_store_class) do Class.new(Gitlab::Redis::Wrapper) do def config_file_name config_file_name = "spec/fixtures/config/redis_new_format_host.yml" Rails.root.join(config_file_name).to_s end def self.name 'Sessions' end end end let_it_be(:primary_db) { 1 } let_it_be(:secondary_db) { 2 } let_it_be(:primary_store) { create_redis_store(redis_store_class.params, db: primary_db, serializer: nil) } let_it_be(:secondary_store) { create_redis_store(redis_store_class.params, db: secondary_db, serializer: nil) } let_it_be(:instance_name) { 'TestStore' } let_it_be(:multi_store) { described_class.new(primary_store, secondary_store, instance_name)} subject { multi_store.send(name, *args) } before do skip_feature_flags_yaml_validation skip_default_enabled_yaml_check end after(:all) do primary_store.flushdb secondary_store.flushdb end context 'when primary_store is nil' do let(:multi_store) { described_class.new(nil, secondary_store, instance_name)} it 'fails with exception' do expect { multi_store }.to raise_error(ArgumentError, /primary_store is required/) end end context 'when secondary_store is nil' do let(:multi_store) { described_class.new(primary_store, nil, instance_name)} it 'fails with exception' do expect { multi_store }.to raise_error(ArgumentError, /secondary_store is required/) end end context 'when instance_name is nil' do let(:instance_name) { nil } let(:multi_store) { described_class.new(primary_store, secondary_store, instance_name)} it 'fails with exception' do expect { multi_store }.to raise_error(ArgumentError, /instance_name is required/) end end context 'when primary_store is not a ::Redis instance' do before do allow(primary_store).to receive(:is_a?).with(::Redis).and_return(false) allow(primary_store).to receive(:is_a?).with(::Redis::Namespace).and_return(false) end it 'fails with exception' do expect { described_class.new(primary_store, secondary_store, instance_name) } .to raise_error(ArgumentError, /invalid primary_store/) end end context 'when primary_store is a ::Redis::Namespace instance' do before do allow(primary_store).to receive(:is_a?).with(::Redis).and_return(false) allow(primary_store).to receive(:is_a?).with(::Redis::Namespace).and_return(true) end it 'fails with exception' do expect { described_class.new(primary_store, secondary_store, instance_name) }.not_to raise_error end end context 'when secondary_store is not a ::Redis instance' do before do allow(secondary_store).to receive(:is_a?).with(::Redis).and_return(false) allow(secondary_store).to receive(:is_a?).with(::Redis::Namespace).and_return(false) end it 'fails with exception' do expect { described_class.new(primary_store, secondary_store, instance_name) } .to raise_error(ArgumentError, /invalid secondary_store/) end end context 'when secondary_store is a ::Redis::Namespace instance' do before do allow(secondary_store).to receive(:is_a?).with(::Redis).and_return(false) allow(secondary_store).to receive(:is_a?).with(::Redis::Namespace).and_return(true) end it 'fails with exception' do expect { described_class.new(primary_store, secondary_store, instance_name) }.not_to raise_error end end context 'with READ redis commands' do let_it_be(:key1) { "redis:{1}:key_a" } let_it_be(:key2) { "redis:{1}:key_b" } let_it_be(:value1) { "redis_value1"} let_it_be(:value2) { "redis_value2"} let_it_be(:skey) { "redis:set:key" } let_it_be(:keys) { [key1, key2] } let_it_be(:values) { [value1, value2] } let_it_be(:svalues) { [value2, value1] } where(:case_name, :name, :args, :value, :block) do 'execute :get command' | :get | ref(:key1) | ref(:value1) | nil 'execute :mget command' | :mget | ref(:keys) | ref(:values) | nil 'execute :mget with block' | :mget | ref(:keys) | ref(:values) | ->(value) { value } 'execute :smembers command' | :smembers | ref(:skey) | ref(:svalues) | nil 'execute :scard command' | :scard | ref(:skey) | 2 | nil end before(:all) do primary_store.multi do |multi| multi.set(key1, value1) multi.set(key2, value2) multi.sadd(skey, value1) multi.sadd(skey, value2) end secondary_store.multi do |multi| multi.set(key1, value1) multi.set(key2, value2) multi.sadd(skey, value1) multi.sadd(skey, value2) end end RSpec.shared_examples_for 'reads correct value' do it 'returns the correct value' do if value.is_a?(Array) # :smembers does not guarantee the order it will return the values (unsorted set) is_expected.to match_array(value) else is_expected.to eq(value) end end end RSpec.shared_examples_for 'fallback read from the secondary store' do let(:counter) { Gitlab::Metrics::NullMetric.instance } before do allow(Gitlab::Metrics).to receive(:counter).and_return(counter) end it 'fallback and execute on secondary instance' do expect(secondary_store).to receive(name).with(*args).and_call_original subject end it 'logs the ReadFromPrimaryError' do expect(Gitlab::ErrorTracking).to receive(:log_exception).with( an_instance_of(Gitlab::Redis::MultiStore::ReadFromPrimaryError), hash_including(command_name: name, instance_name: instance_name) ) subject end it 'increment read fallback count metrics' do expect(counter).to receive(:increment).with(command: name, instance_name: instance_name) subject end include_examples 'reads correct value' context 'when fallback read from the secondary instance raises an exception' do before do allow(secondary_store).to receive(name).with(*args).and_raise(StandardError) end it 'fails with exception' do expect { subject }.to raise_error(StandardError) end end end RSpec.shared_examples_for 'secondary store' do it 'execute on the secondary instance' do expect(secondary_store).to receive(name).with(*args).and_call_original subject end include_examples 'reads correct value' it 'does not execute on the primary store' do expect(primary_store).not_to receive(name) subject end end with_them do describe "#{name}" do before do allow(primary_store).to receive(name).and_call_original allow(secondary_store).to receive(name).and_call_original end context 'with feature flag :use_primary_and_secondary_stores_for_test_store' do before do stub_feature_flags(use_primary_and_secondary_stores_for_test_store: true) end context 'when reading from the primary is successful' do it 'returns the correct value' do expect(primary_store).to receive(name).with(*args).and_call_original subject end it 'does not execute on the secondary store' do expect(secondary_store).not_to receive(name) subject end include_examples 'reads correct value' end context 'when reading from primary instance is raising an exception' do before do allow(primary_store).to receive(name).with(*args).and_raise(StandardError) allow(Gitlab::ErrorTracking).to receive(:log_exception) end it 'logs the exception' do expect(Gitlab::ErrorTracking).to receive(:log_exception).with(an_instance_of(StandardError), hash_including(:multi_store_error_message, instance_name: instance_name, command_name: name)) subject end include_examples 'fallback read from the secondary store' end context 'when reading from primary instance return no value' do before do allow(primary_store).to receive(name).and_return(nil) end include_examples 'fallback read from the secondary store' end context 'when the command is executed within pipelined block' do subject do multi_store.pipelined do multi_store.send(name, *args) end end it 'is executed only 1 time on primary instance' do expect(primary_store).to receive(name).with(*args).once subject end end if params[:block] subject do multi_store.send(name, *args, &block) end context 'when block is provided' do it 'yields to the block' do expect(primary_store).to receive(name).and_yield(value) subject end include_examples 'reads correct value' end end end context 'with feature flag :use_primary_and_secondary_stores_for_test_store' do before do stub_feature_flags(use_primary_and_secondary_stores_for_test_store: false) end context 'with feature flag :use_primary_store_as_default_for_test_store is disabled' do before do stub_feature_flags(use_primary_store_as_default_for_test_store: false) end it_behaves_like 'secondary store' end context 'with feature flag :use_primary_store_as_default_for_test_store is enabled' do before do stub_feature_flags(use_primary_store_as_default_for_test_store: true) end it 'execute on the primary instance' do expect(primary_store).to receive(name).with(*args).and_call_original subject end include_examples 'reads correct value' it 'does not execute on the secondary store' do expect(secondary_store).not_to receive(name) subject end end end context 'with both primary and secondary store using same redis instance' do let(:primary_store) { create_redis_store(redis_store_class.params, db: primary_db, serializer: nil) } let(:secondary_store) { create_redis_store(redis_store_class.params, db: primary_db, serializer: nil) } let(:multi_store) { described_class.new(primary_store, secondary_store, instance_name)} it_behaves_like 'secondary store' end end end end RSpec.shared_examples_for 'verify that store contains values' do |store| it "#{store} redis store contains correct values", :aggregate_errors do subject redis_store = multi_store.send(store) if expected_value.is_a?(Array) # :smembers does not guarantee the order it will return the values expect(redis_store.send(verification_name, *verification_args)).to match_array(expected_value) else expect(redis_store.send(verification_name, *verification_args)).to eq(expected_value) end end end context 'with WRITE redis commands' do let_it_be(:key1) { "redis:{1}:key_a" } let_it_be(:key2) { "redis:{1}:key_b" } let_it_be(:value1) { "redis_value1"} let_it_be(:value2) { "redis_value2"} let_it_be(:key1_value1) { [key1, value1] } let_it_be(:key1_value2) { [key1, value2] } let_it_be(:ttl) { 10 } let_it_be(:key1_ttl_value1) { [key1, ttl, value1] } let_it_be(:skey) { "redis:set:key" } let_it_be(:svalues1) { [value2, value1] } let_it_be(:svalues2) { [value1] } let_it_be(:skey_value1) { [skey, value1] } let_it_be(:skey_value2) { [skey, value2] } where(:case_name, :name, :args, :expected_value, :verification_name, :verification_args) do 'execute :set command' | :set | ref(:key1_value1) | ref(:value1) | :get | ref(:key1) 'execute :setnx command' | :setnx | ref(:key1_value2) | ref(:value1) | :get | ref(:key2) 'execute :setex command' | :setex | ref(:key1_ttl_value1) | ref(:ttl) | :ttl | ref(:key1) 'execute :sadd command' | :sadd | ref(:skey_value2) | ref(:svalues1) | :smembers | ref(:skey) 'execute :srem command' | :srem | ref(:skey_value1) | [] | :smembers | ref(:skey) 'execute :del command' | :del | ref(:key2) | nil | :get | ref(:key2) 'execute :flushdb command' | :flushdb | nil | 0 | :dbsize | nil end before do primary_store.flushdb secondary_store.flushdb primary_store.multi do |multi| multi.set(key2, value1) multi.sadd(skey, value1) end secondary_store.multi do |multi| multi.set(key2, value1) multi.sadd(skey, value1) end end with_them do describe "#{name}" do let(:expected_args) {args || no_args } before do allow(primary_store).to receive(name).and_call_original allow(secondary_store).to receive(name).and_call_original end context 'with feature flag :use_primary_and_secondary_stores_for_test_store' do before do stub_feature_flags(use_primary_and_secondary_stores_for_test_store: true) end context 'when executing on primary instance is successful' do it 'executes on both primary and secondary redis store', :aggregate_errors do expect(primary_store).to receive(name).with(*expected_args).and_call_original expect(secondary_store).to receive(name).with(*expected_args).and_call_original subject end include_examples 'verify that store contains values', :primary_store include_examples 'verify that store contains values', :secondary_store end context 'when executing on the primary instance is raising an exception' do before do allow(primary_store).to receive(name).with(*expected_args).and_raise(StandardError) allow(Gitlab::ErrorTracking).to receive(:log_exception) end it 'logs the exception and execute on secondary instance', :aggregate_errors do expect(Gitlab::ErrorTracking).to receive(:log_exception).with(an_instance_of(StandardError), hash_including(:multi_store_error_message, command_name: name, instance_name: instance_name)) expect(secondary_store).to receive(name).with(*expected_args).and_call_original subject end include_examples 'verify that store contains values', :secondary_store end context 'when the command is executed within pipelined block' do subject do multi_store.pipelined do multi_store.send(name, *args) end end it 'is executed only 1 time on each instance', :aggregate_errors do expect(primary_store).to receive(name).with(*expected_args).once expect(secondary_store).to receive(name).with(*expected_args).once subject end include_examples 'verify that store contains values', :primary_store include_examples 'verify that store contains values', :secondary_store end end context 'with feature flag :use_primary_and_secondary_stores_for_test_store is disabled' do before do stub_feature_flags(use_primary_and_secondary_stores_for_test_store: false) end context 'with feature flag :use_primary_store_as_default_for_test_store is disabled' do before do stub_feature_flags(use_primary_store_as_default_for_test_store: false) end it 'executes only on the secondary redis store', :aggregate_errors do expect(secondary_store).to receive(name).with(*expected_args) expect(primary_store).not_to receive(name).with(*expected_args) subject end include_examples 'verify that store contains values', :secondary_store end context 'with feature flag :use_primary_store_as_default_for_test_store is enabled' do before do stub_feature_flags(use_primary_store_as_default_for_test_store: true) end it 'executes only on the primary_redis redis store', :aggregate_errors do expect(primary_store).to receive(name).with(*expected_args) expect(secondary_store).not_to receive(name).with(*expected_args) subject end include_examples 'verify that store contains values', :primary_store end end end end end RSpec.shared_examples_for 'pipelined command' do |name| let_it_be(:key1) { "redis:{1}:key_a" } let_it_be(:value1) { "redis_value1"} let_it_be(:value2) { "redis_value2"} let_it_be(:expected_value) { value1 } let_it_be(:verification_name) { :get } let_it_be(:verification_args) { key1 } before do primary_store.flushdb secondary_store.flushdb end describe "command execution in a transaction" do let(:counter) { Gitlab::Metrics::NullMetric.instance } before do allow(Gitlab::Metrics).to receive(:counter).with( :gitlab_redis_multi_store_pipelined_diff_error_total, 'Redis MultiStore pipelined command diff between stores' ).and_return(counter) end subject do multi_store.send(name) do |redis| redis.set(key1, value1) end end context 'with feature flag :use_primary_and_secondary_stores_for_test_store' do before do stub_feature_flags(use_primary_and_secondary_stores_for_test_store: true) end context 'when executing on primary instance is successful' do it 'executes on both primary and secondary redis store', :aggregate_errors do expect(primary_store).to receive(name).and_call_original expect(secondary_store).to receive(name).and_call_original subject end include_examples 'verify that store contains values', :primary_store include_examples 'verify that store contains values', :secondary_store end context 'when executing on the primary instance is raising an exception' do before do allow(primary_store).to receive(name).and_raise(StandardError) allow(Gitlab::ErrorTracking).to receive(:log_exception) end it 'logs the exception and execute on secondary instance', :aggregate_errors do expect(Gitlab::ErrorTracking).to receive(:log_exception).with(an_instance_of(StandardError), hash_including(:multi_store_error_message, command_name: name)) expect(secondary_store).to receive(name).and_call_original subject end include_examples 'verify that store contains values', :secondary_store end describe 'return values from a transaction' do subject do multi_store.send(name) do |redis| redis.get(key1) end end context 'when the value exists on both and are equal' do before do primary_store.set(key1, value1) secondary_store.set(key1, value1) end it 'returns the value' do expect(Gitlab::ErrorTracking).not_to receive(:log_exception) expect(subject).to eq([value1]) end end context 'when the value exists on both but differ' do before do primary_store.set(key1, value1) secondary_store.set(key1, value2) end it 'returns the value from the secondary store, logging an error' do expect(Gitlab::ErrorTracking).to receive(:log_exception).with( an_instance_of(Gitlab::Redis::MultiStore::PipelinedDiffError), hash_including(command_name: name, instance_name: instance_name) ).and_call_original expect(counter).to receive(:increment).with(command: name, instance_name: instance_name) expect(subject).to eq([value2]) end end context 'when the value does not exist on the primary but it does on the secondary' do before do secondary_store.set(key1, value2) end it 'returns the value from the secondary store, logging an error' do expect(Gitlab::ErrorTracking).to receive(:log_exception).with( an_instance_of(Gitlab::Redis::MultiStore::PipelinedDiffError), hash_including(command_name: name, instance_name: instance_name) ) expect(counter).to receive(:increment).with(command: name, instance_name: instance_name) expect(subject).to eq([value2]) end end context 'when the value does not exist in either' do it 'returns nil without logging an error' do expect(Gitlab::ErrorTracking).not_to receive(:log_exception) expect(counter).not_to receive(:increment) expect(subject).to eq([nil]) end end end end context 'with feature flag :use_primary_and_secondary_stores_for_test_store is disabled' do before do stub_feature_flags(use_primary_and_secondary_stores_for_test_store: false) end context 'with feature flag :use_primary_store_as_default_for_test_store is disabled' do before do stub_feature_flags(use_primary_store_as_default_for_test_store: false) end it 'executes only on the secondary redis store', :aggregate_errors do expect(secondary_store).to receive(name) expect(primary_store).not_to receive(name) subject end include_examples 'verify that store contains values', :secondary_store end context 'with feature flag :use_primary_store_as_default_for_test_store is enabled' do before do stub_feature_flags(use_primary_store_as_default_for_test_store: true) end it 'executes only on the primary_redis redis store', :aggregate_errors do expect(primary_store).to receive(name) expect(secondary_store).not_to receive(name) subject end include_examples 'verify that store contains values', :primary_store end end end end describe '#multi' do include_examples 'pipelined command', :multi end describe '#pipelined' do include_examples 'pipelined command', :pipelined end context 'with unsupported command' do let(:counter) { Gitlab::Metrics::NullMetric.instance } before do primary_store.flushdb secondary_store.flushdb allow(Gitlab::Metrics).to receive(:counter).and_return(counter) end let_it_be(:key) { "redis:counter" } subject { multi_store.incr(key) } it 'responds to missing method' do expect(multi_store).to receive(:respond_to_missing?).and_call_original expect(multi_store.respond_to?(:incr)).to be(true) end it 'executes method missing' do expect(multi_store).to receive(:method_missing) subject end context 'when command is not in SKIP_LOG_METHOD_MISSING_FOR_COMMANDS' do it 'logs MethodMissingError' do expect(Gitlab::ErrorTracking).to receive(:log_exception).with( an_instance_of(Gitlab::Redis::MultiStore::MethodMissingError), hash_including(command_name: :incr, instance_name: instance_name) ) subject end it 'increments method missing counter' do expect(counter).to receive(:increment).with(command: :incr, instance_name: instance_name) subject end end context 'when command is in SKIP_LOG_METHOD_MISSING_FOR_COMMANDS' do subject { multi_store.info } it 'does not log MethodMissingError' do expect(Gitlab::ErrorTracking).not_to receive(:log_exception) subject end it 'does not increment method missing counter' do expect(counter).not_to receive(:increment) subject end end context 'with feature flag :use_primary_store_as_default_for_test_store is enabled' do before do stub_feature_flags(use_primary_store_as_default_for_test_store: true) end it 'fallback and executes only on the secondary store', :aggregate_errors do expect(primary_store).to receive(:incr).with(key).and_call_original expect(secondary_store).not_to receive(:incr) subject end it 'correct value is stored on the secondary store', :aggregate_errors do subject expect(secondary_store.get(key)).to be_nil expect(primary_store.get(key)).to eq('1') end end context 'with feature flag :use_primary_store_as_default_for_test_store is disabled' do before do stub_feature_flags(use_primary_store_as_default_for_test_store: false) end it 'fallback and executes only on the secondary store', :aggregate_errors do expect(secondary_store).to receive(:incr).with(key).and_call_original expect(primary_store).not_to receive(:incr) subject end it 'correct value is stored on the secondary store', :aggregate_errors do subject expect(primary_store.get(key)).to be_nil expect(secondary_store.get(key)).to eq('1') end end context 'when the command is executed within pipelined block' do subject do multi_store.pipelined do multi_store.incr(key) end end it 'is executed only 1 time on each instance', :aggregate_errors do expect(primary_store).to receive(:incr).with(key).once expect(secondary_store).to receive(:incr).with(key).once subject end it "both redis stores are containing correct values", :aggregate_errors do subject expect(primary_store.get(key)).to eq('1') expect(secondary_store.get(key)).to eq('1') end end end describe '#to_s' do subject { multi_store.to_s } context 'with feature flag :use_primary_and_secondary_stores_for_test_store is enabled' do before do stub_feature_flags(use_primary_and_secondary_stores_for_test_store: true) end it 'returns same value as primary_store' do is_expected.to eq(primary_store.to_s) end end context 'with feature flag :use_primary_and_secondary_stores_for_test_store is disabled' do before do stub_feature_flags(use_primary_and_secondary_stores_for_test_store: false) end context 'with feature flag :use_primary_store_as_default_for_test_store is enabled' do before do stub_feature_flags(use_primary_store_as_default_for_test_store: true) end it 'returns same value as primary_store' do is_expected.to eq(primary_store.to_s) end end context 'with feature flag :use_primary_store_as_default_for_test_store is disabled' do before do stub_feature_flags(use_primary_store_as_default_for_test_store: false) end it 'returns same value as primary_store' do is_expected.to eq(secondary_store.to_s) end end end end describe '#is_a?' do it 'returns true for ::Redis::Store' do expect(multi_store.is_a?(::Redis::Store)).to be true end end describe '#use_primary_and_secondary_stores?' do context 'with feature flag :use_primary_and_secondary_stores_for_test_store is enabled' do before do stub_feature_flags(use_primary_and_secondary_stores_for_test_store: true) end it 'multi store is disabled' do expect(multi_store.use_primary_and_secondary_stores?).to be true end end context 'with feature flag :use_primary_and_secondary_stores_for_test_store is disabled' do before do stub_feature_flags(use_primary_and_secondary_stores_for_test_store: false) end it 'multi store is disabled' do expect(multi_store.use_primary_and_secondary_stores?).to be false end end context 'with empty DB' do before do allow(Feature::FlipperFeature).to receive(:table_exists?).and_return(false) end it 'multi store is disabled' do expect(multi_store.use_primary_and_secondary_stores?).to be false end end context 'when FF table guard raises' do before do allow(Feature::FlipperFeature).to receive(:table_exists?).and_raise end it 'multi store is disabled' do expect(multi_store.use_primary_and_secondary_stores?).to be false end end end describe '#use_primary_store_as_default?' do context 'with feature flag :use_primary_store_as_default_for_test_store is enabled' do before do stub_feature_flags(use_primary_store_as_default_for_test_store: true) end it 'multi store is disabled' do expect(multi_store.use_primary_store_as_default?).to be true end end context 'with feature flag :use_primary_store_as_default_for_test_store is disabled' do before do stub_feature_flags(use_primary_store_as_default_for_test_store: false) end it 'multi store is disabled' do expect(multi_store.use_primary_store_as_default?).to be false end end context 'with empty DB' do before do allow(Feature::FlipperFeature).to receive(:table_exists?).and_return(false) end it 'multi store is disabled' do expect(multi_store.use_primary_and_secondary_stores?).to be false end end context 'when FF table guard raises' do before do allow(Feature::FlipperFeature).to receive(:table_exists?).and_raise end it 'multi store is disabled' do expect(multi_store.use_primary_and_secondary_stores?).to be false end end end def create_redis_store(options, extras = {}) ::Redis::Store.new(options.merge(extras)) end end