summaryrefslogtreecommitdiff
path: root/spec/lib/feature_spec.rb
blob: 5dff9dbd99518c78744a3558ad96bca0725a94c6 (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
# frozen_string_literal: true

require 'spec_helper'

RSpec.describe Feature, stub_feature_flags: false do
  before do
    # reset Flipper AR-engine
    Feature.reset
    skip_feature_flags_yaml_validation
  end

  describe '.get' do
    let(:feature) { double(:feature) }
    let(:key) { 'my_feature' }

    it 'returns the Flipper feature' do
      expect_any_instance_of(Flipper::DSL).to receive(:feature).with(key)
        .and_return(feature)

      expect(described_class.get(key)).to be(feature)
    end
  end

  describe '.persisted_names' do
    it 'returns the names of the persisted features' do
      Feature.enable('foo')

      expect(described_class.persisted_names).to contain_exactly('foo')
    end

    it 'returns an empty Array when no features are presisted' do
      expect(described_class.persisted_names).to be_empty
    end

    it 'caches the feature names when request store is active',
      :request_store, :use_clean_rails_memory_store_caching do
      Feature.enable('foo')

      expect(Gitlab::ProcessMemoryCache.cache_backend)
        .to receive(:fetch)
        .once
        .with('flipper/v1/features', expires_in: 1.minute)
        .and_call_original

      2.times do
        expect(described_class.persisted_names).to contain_exactly('foo')
      end
    end

    it 'fetches all flags once in a single query', :request_store do
      Feature.enable('foo1')
      Feature.enable('foo2')

      queries = ActiveRecord::QueryRecorder.new(skip_cached: false) do
        expect(described_class.persisted_names).to contain_exactly('foo1', 'foo2')

        RequestStore.clear!

        expect(described_class.persisted_names).to contain_exactly('foo1', 'foo2')
      end

      expect(queries.count).to eq(1)
    end
  end

  describe '.persisted_name?' do
    context 'when the feature is persisted' do
      it 'returns true when feature name is a string' do
        Feature.enable('foo')

        expect(described_class.persisted_name?('foo')).to eq(true)
      end

      it 'returns true when feature name is a symbol' do
        Feature.enable('foo')

        expect(described_class.persisted_name?(:foo)).to eq(true)
      end
    end

    context 'when the feature is not persisted' do
      it 'returns false when feature name is a string' do
        expect(described_class.persisted_name?('foo')).to eq(false)
      end

      it 'returns false when feature name is a symbol' do
        expect(described_class.persisted_name?(:bar)).to eq(false)
      end
    end
  end

  describe '.all' do
    let(:features) { Set.new }

    it 'returns the Flipper features as an array' do
      expect_any_instance_of(Flipper::DSL).to receive(:features)
        .and_return(features)

      expect(described_class.all).to eq(features.to_a)
    end
  end

  describe '.flipper' do
    context 'when request store is inactive' do
      it 'memoizes the Flipper instance' do
        expect(Flipper).to receive(:new).once.and_call_original

        2.times do
          described_class.send(:flipper)
        end
      end
    end

    context 'when request store is active', :request_store do
      it 'memoizes the Flipper instance' do
        expect(Flipper).to receive(:new).once.and_call_original

        described_class.send(:flipper)
        described_class.instance_variable_set(:@flipper, nil)
        described_class.send(:flipper)
      end
    end
  end

  describe '.enabled?' do
    it 'returns false for undefined feature' do
      expect(described_class.enabled?(:some_random_feature_flag)).to be_falsey
    end

    it 'returns true for undefined feature with default_enabled' do
      expect(described_class.enabled?(:some_random_feature_flag, default_enabled: true)).to be_truthy
    end

    it 'returns false for existing disabled feature in the database' do
      described_class.disable(:disabled_feature_flag)

      expect(described_class.enabled?(:disabled_feature_flag)).to be_falsey
    end

    it 'returns true for existing enabled feature in the database' do
      described_class.enable(:enabled_feature_flag)

      expect(described_class.enabled?(:enabled_feature_flag)).to be_truthy
    end

    it { expect(described_class.send(:l1_cache_backend)).to eq(Gitlab::ProcessMemoryCache.cache_backend) }
    it { expect(described_class.send(:l2_cache_backend)).to eq(Rails.cache) }

    it 'caches the status in L1 and L2 caches',
       :request_store, :use_clean_rails_memory_store_caching do
      described_class.enable(:enabled_feature_flag)
      flipper_key = "flipper/v1/feature/enabled_feature_flag"

      expect(described_class.send(:l2_cache_backend))
        .to receive(:fetch)
        .once
        .with(flipper_key, expires_in: 1.hour)
        .and_call_original

      expect(described_class.send(:l1_cache_backend))
        .to receive(:fetch)
        .once
        .with(flipper_key, expires_in: 1.minute)
        .and_call_original

      2.times do
        expect(described_class.enabled?(:enabled_feature_flag)).to be_truthy
      end
    end

    it 'returns the default value when the database does not exist' do
      fake_default = double('fake default')
      expect(ActiveRecord::Base).to receive(:connection) { raise ActiveRecord::NoDatabaseError, "No database" }

      expect(described_class.enabled?(:a_feature, default_enabled: fake_default)).to eq(fake_default)
    end

    context 'cached feature flag', :request_store do
      let(:flag) { :some_feature_flag }

      before do
        described_class.send(:flipper).memoize = false
        described_class.enabled?(flag)
      end

      it 'caches the status in L1 cache for the first minute' do
        expect do
          expect(described_class.send(:l1_cache_backend)).to receive(:fetch).once.and_call_original
          expect(described_class.send(:l2_cache_backend)).not_to receive(:fetch)
          expect(described_class.enabled?(flag)).to be_truthy
        end.not_to exceed_query_limit(0)
      end

      it 'caches the status in L2 cache after 2 minutes' do
        Timecop.travel 2.minutes do
          expect do
            expect(described_class.send(:l1_cache_backend)).to receive(:fetch).once.and_call_original
            expect(described_class.send(:l2_cache_backend)).to receive(:fetch).once.and_call_original
            expect(described_class.enabled?(flag)).to be_truthy
          end.not_to exceed_query_limit(0)
        end
      end

      it 'fetches the status after an hour' do
        Timecop.travel 61.minutes do
          expect do
            expect(described_class.send(:l1_cache_backend)).to receive(:fetch).once.and_call_original
            expect(described_class.send(:l2_cache_backend)).to receive(:fetch).once.and_call_original
            expect(described_class.enabled?(flag)).to be_truthy
          end.not_to exceed_query_limit(1)
        end
      end
    end

    context 'with an individual actor' do
      let(:actor) { stub_feature_flag_gate('CustomActor:5') }
      let(:another_actor) { stub_feature_flag_gate('CustomActor:10') }

      before do
        described_class.enable(:enabled_feature_flag, actor)
      end

      it 'returns true when same actor is informed' do
        expect(described_class.enabled?(:enabled_feature_flag, actor)).to be_truthy
      end

      it 'returns false when different actor is informed' do
        expect(described_class.enabled?(:enabled_feature_flag, another_actor)).to be_falsey
      end

      it 'returns false when no actor is informed' do
        expect(described_class.enabled?(:enabled_feature_flag)).to be_falsey
      end
    end

    context 'with invalid actor' do
      let(:actor) { double('invalid actor') }

      context 'when is dev_or_test_env' do
        it 'does raise exception' do
          expect { described_class.enabled?(:enabled_feature_flag, actor) }
            .to raise_error /needs to include `FeatureGate` or implement `flipper_id`/
        end
      end
    end

    context 'validates usage of feature flag with YAML definition' do
      let(:definition) do
        Feature::Definition.new('development/my_feature_flag.yml',
          name: 'my_feature_flag',
          type: 'development',
          default_enabled: false
        ).tap(&:validate!)
      end

      before do
        stub_env('LAZILY_CREATE_FEATURE_FLAG', '0')

        allow(Feature::Definition).to receive(:valid_usage!).and_call_original
        allow(Feature::Definition).to receive(:definitions) do
          { definition.key => definition }
        end
      end

      it 'when usage is correct' do
        expect { described_class.enabled?(:my_feature_flag) }.not_to raise_error
      end

      it 'when invalid type is used' do
        expect { described_class.enabled?(:my_feature_flag, type: :licensed) }
          .to raise_error(/The `type:` of/)
      end

      it 'when invalid default_enabled is used' do
        expect { described_class.enabled?(:my_feature_flag, default_enabled: true) }
          .to raise_error(/The `default_enabled:` of/)
      end
    end
  end

  describe '.disable?' do
    it 'returns true for undefined feature' do
      expect(described_class.disabled?(:some_random_feature_flag)).to be_truthy
    end

    it 'returns false for undefined feature with default_enabled' do
      expect(described_class.disabled?(:some_random_feature_flag, default_enabled: true)).to be_falsey
    end

    it 'returns true for existing disabled feature in the database' do
      described_class.disable(:disabled_feature_flag)

      expect(described_class.disabled?(:disabled_feature_flag)).to be_truthy
    end

    it 'returns false for existing enabled feature in the database' do
      described_class.enable(:enabled_feature_flag)

      expect(described_class.disabled?(:enabled_feature_flag)).to be_falsey
    end
  end

  describe '.remove' do
    context 'for a non-persisted feature' do
      it 'returns nil' do
        expect(described_class.remove(:non_persisted_feature_flag)).to be_nil
      end
    end

    context 'for a persisted feature' do
      it 'returns true' do
        described_class.enable(:persisted_feature_flag)

        expect(described_class.remove(:persisted_feature_flag)).to be_truthy
      end
    end
  end

  describe Feature::Target do
    describe '#targets' do
      let(:project) { create(:project) }
      let(:group) { create(:group) }
      let(:user_name) { project.owner.username }

      subject { described_class.new(user: user_name, project: project.full_path, group: group.full_path) }

      it 'returns all found targets' do
        expect(subject.targets).to be_an(Array)
        expect(subject.targets).to eq([project.owner, project, group])
      end
    end
  end
end