debian-mirror-gitlab/spec/lib/feature_spec.rb
2021-10-27 15:23:28 +05:30

596 lines
20 KiB
Ruby

# 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: default_enabled
).tap(&:validate!)
end
let(:default_enabled) { false }
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: :ops) }
.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
context 'when `default_enabled: :yaml` is used in code' do
it 'reads the default from the YAML definition' do
expect(described_class.enabled?(:my_feature_flag, default_enabled: :yaml)).to eq(false)
end
context 'when default_enabled is true in the YAML definition' do
let(:default_enabled) { true }
it 'reads the default from the YAML definition' do
expect(described_class.enabled?(:my_feature_flag, default_enabled: :yaml)).to eq(true)
end
end
context 'when YAML definition does not exist for an optional type' do
let(:optional_type) { described_class::Shared::TYPES.find { |name, attrs| attrs[:optional] }.first }
context 'when in dev or test environment' do
it 'raises an error for dev' do
expect { described_class.enabled?(:non_existent_flag, type: optional_type, default_enabled: :yaml) }
.to raise_error(
Feature::InvalidFeatureFlagError,
"The feature flag YAML definition for 'non_existent_flag' does not exist")
end
end
context 'when in production' do
before do
allow(Gitlab::ErrorTracking).to receive(:should_raise_for_dev?).and_return(false)
end
context 'when database exists' do
before do
allow(Gitlab::Database.main).to receive(:exists?).and_return(true)
end
it 'checks the persisted status and returns false' do
expect(described_class).to receive(:get).with(:non_existent_flag).and_call_original
expect(described_class.enabled?(:non_existent_flag, type: optional_type, default_enabled: :yaml)).to eq(false)
end
end
context 'when database does not exist' do
before do
allow(Gitlab::Database.main).to receive(:exists?).and_return(false)
end
it 'returns false without checking the status in the database' do
expect(described_class).not_to receive(:get)
expect(described_class.enabled?(:non_existent_flag, type: optional_type, default_enabled: :yaml)).to eq(false)
end
end
end
end
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
shared_examples_for 'logging' do
let(:expected_action) { }
let(:expected_extra) { }
it 'logs the event' do
expect(Feature.logger).to receive(:info).with(key: key, action: expected_action, **expected_extra)
subject
end
end
describe '.enable' do
subject { described_class.enable(key, thing) }
let(:key) { :awesome_feature }
let(:thing) { true }
it_behaves_like 'logging' do
let(:expected_action) { :enable }
let(:expected_extra) { { "extra.thing" => "true" } }
end
context 'when thing is an actor' do
let(:thing) { create(:project) }
it_behaves_like 'logging' do
let(:expected_action) { :enable }
let(:expected_extra) { { "extra.thing" => "#{thing.flipper_id}" } }
end
end
end
describe '.disable' do
subject { described_class.disable(key, thing) }
let(:key) { :awesome_feature }
let(:thing) { false }
it_behaves_like 'logging' do
let(:expected_action) { :disable }
let(:expected_extra) { { "extra.thing" => "false" } }
end
context 'when thing is an actor' do
let(:thing) { create(:project) }
it_behaves_like 'logging' do
let(:expected_action) { :disable }
let(:expected_extra) { { "extra.thing" => "#{thing.flipper_id}" } }
end
end
end
describe '.enable_percentage_of_time' do
subject { described_class.enable_percentage_of_time(key, percentage) }
let(:key) { :awesome_feature }
let(:percentage) { 50 }
it_behaves_like 'logging' do
let(:expected_action) { :enable_percentage_of_time }
let(:expected_extra) { { "extra.percentage" => "#{percentage}" } }
end
end
describe '.disable_percentage_of_time' do
subject { described_class.disable_percentage_of_time(key) }
let(:key) { :awesome_feature }
it_behaves_like 'logging' do
let(:expected_action) { :disable_percentage_of_time }
let(:expected_extra) { {} }
end
end
describe '.enable_percentage_of_actors' do
subject { described_class.enable_percentage_of_actors(key, percentage) }
let(:key) { :awesome_feature }
let(:percentage) { 50 }
it_behaves_like 'logging' do
let(:expected_action) { :enable_percentage_of_actors }
let(:expected_extra) { { "extra.percentage" => "#{percentage}" } }
end
end
describe '.disable_percentage_of_actors' do
subject { described_class.disable_percentage_of_actors(key) }
let(:key) { :awesome_feature }
it_behaves_like 'logging' do
let(:expected_action) { :disable_percentage_of_actors }
let(:expected_extra) { {} }
end
end
describe '.remove' do
subject { described_class.remove(key) }
let(:key) { :awesome_feature }
before do
described_class.enable(key)
end
it_behaves_like 'logging' do
let(:expected_action) { :remove }
let(:expected_extra) { {} }
end
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
context 'caching with stale reads from the database', :use_clean_rails_redis_caching, :request_store, :aggregate_failures do
let(:actor) { stub_feature_flag_gate('CustomActor:5') }
let(:another_actor) { stub_feature_flag_gate('CustomActor:10') }
# This is a bit unpleasant. For these tests we want to simulate stale reads
# from the database (due to database load balancing). A simple way to do
# that is to stub the response on the adapter Flipper uses for reading from
# the database. However, there isn't a convenient API for this. We know that
# the ActiveRecord adapter is always at the 'bottom' of the chain, so we can
# find it that way.
let(:active_record_adapter) do
adapter = described_class.flipper
loop do
break adapter unless adapter.instance_variable_get(:@adapter)
adapter = adapter.instance_variable_get(:@adapter)
end
end
it 'gives the correct value when enabling for an additional actor' do
described_class.enable(:enabled_feature_flag, actor)
initial_gate_values = active_record_adapter.get(described_class.get(:enabled_feature_flag))
# This should only be enabled for `actor`
expect(described_class.enabled?(:enabled_feature_flag, actor)).to be(true)
expect(described_class.enabled?(:enabled_feature_flag, another_actor)).to be(false)
expect(described_class.enabled?(:enabled_feature_flag)).to be(false)
# Enable for `another_actor` and simulate a stale read
described_class.enable(:enabled_feature_flag, another_actor)
allow(active_record_adapter).to receive(:get).once.and_return(initial_gate_values)
# Should read from the cache and be enabled for both of these actors
expect(described_class.enabled?(:enabled_feature_flag, actor)).to be(true)
expect(described_class.enabled?(:enabled_feature_flag, another_actor)).to be(true)
expect(described_class.enabled?(:enabled_feature_flag)).to be(false)
end
it 'gives the correct value when enabling for percentage of time' do
described_class.enable_percentage_of_time(:enabled_feature_flag, 10)
initial_gate_values = active_record_adapter.get(described_class.get(:enabled_feature_flag))
# Test against `gate_values` directly as otherwise it would be non-determistic
expect(described_class.get(:enabled_feature_flag).gate_values.percentage_of_time).to eq(10)
# Enable 50% of time and simulate a stale read
described_class.enable_percentage_of_time(:enabled_feature_flag, 50)
allow(active_record_adapter).to receive(:get).once.and_return(initial_gate_values)
# Should read from the cache and be enabled 50% of the time
expect(described_class.get(:enabled_feature_flag).gate_values.percentage_of_time).to eq(50)
end
it 'gives the correct value when disabling the flag' do
described_class.enable(:enabled_feature_flag, actor)
described_class.enable(:enabled_feature_flag, another_actor)
initial_gate_values = active_record_adapter.get(described_class.get(:enabled_feature_flag))
# This be enabled for `actor` and `another_actor`
expect(described_class.enabled?(:enabled_feature_flag, actor)).to be(true)
expect(described_class.enabled?(:enabled_feature_flag, another_actor)).to be(true)
expect(described_class.enabled?(:enabled_feature_flag)).to be(false)
# Disable for `another_actor` and simulate a stale read
described_class.disable(:enabled_feature_flag, another_actor)
allow(active_record_adapter).to receive(:get).once.and_return(initial_gate_values)
# Should read from the cache and be enabled only for `actor`
expect(described_class.enabled?(:enabled_feature_flag, actor)).to be(true)
expect(described_class.enabled?(:enabled_feature_flag, another_actor)).to be(false)
expect(described_class.enabled?(:enabled_feature_flag)).to be(false)
end
it 'gives the correct value when deleting the flag' do
described_class.enable(:enabled_feature_flag, actor)
initial_gate_values = active_record_adapter.get(described_class.get(:enabled_feature_flag))
# This should only be enabled for `actor`
expect(described_class.enabled?(:enabled_feature_flag, actor)).to be(true)
expect(described_class.enabled?(:enabled_feature_flag)).to be(false)
# Remove and simulate a stale read
described_class.remove(:enabled_feature_flag)
allow(active_record_adapter).to receive(:get).once.and_return(initial_gate_values)
# Should read from the cache and be disabled everywhere
expect(described_class.enabled?(:enabled_feature_flag, actor)).to be(false)
expect(described_class.enabled?(:enabled_feature_flag)).to be(false)
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