Welcome to mirror list, hosted at ThFree Co, Russian Federation.

multi_store_spec.rb « redis « gitlab « lib « spec - gitlab.com/gitlab-org/gitlab-foss.git - Unnamed repository; edit this file 'description' to name the repository.
summaryrefslogtreecommitdiff
blob: ef8549548d7d6efe76e6d2b68ad7bd04e4733378 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
# 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 pipelined command" 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 pipelined command' do
          RSpec::Matchers.define :pipeline_diff_error_with_stacktrace do |message|
            match do |object|
              expect(object).to be_a(Gitlab::Redis::MultiStore::PipelinedDiffError)
              expect(object.backtrace).not_to be_nil
              expect(object.message).to eq(message)
            end
          end

          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(
                pipeline_diff_error_with_stacktrace(
                  'Pipelined command executed on both stores successfully but results differ between them. ' \
                    "Result from the primary: [#{value1.inspect}]. Result from the secondary: [#{value2.inspect}]."
                ),
                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(
                pipeline_diff_error_with_stacktrace(
                  'Pipelined command executed on both stores successfully but results differ between them. ' \
                    "Result from the primary: [nil]. Result from the secondary: [#{value2.inspect}]."
                ),
                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