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|
require 'rack/test'
require 'active_support/cache'
require 'flipper/adapters/active_support_cache_store'
require 'flipper/adapters/operation_logger'
RSpec.describe Flipper::Middleware::Memoizer do
include Rack::Test::Methods
let(:memory_adapter) { Flipper::Adapters::Memory.new }
let(:adapter) do
Flipper::Adapters::OperationLogger.new(memory_adapter)
end
let(:flipper) { Flipper.new(adapter) }
let(:env) { { 'flipper' => flipper } }
it 'raises if initialized with app and flipper instance' do
expect do
described_class.new(app, flipper)
end.to raise_error(/no longer initializes with a flipper/)
end
it 'raises if initialized with app and block' do
block = -> { flipper }
expect do
described_class.new(app, block)
end.to raise_error(/no longer initializes with a flipper/)
end
RSpec.shared_examples_for 'flipper middleware' do
it 'delegates' do
called = false
app = lambda do |_env|
called = true
[200, {}, nil]
end
middleware = described_class.new(app)
middleware.call(env)
expect(called).to eq(true)
end
it 'clears the local cache with a successful request' do
flipper.adapter.cache['hello'] = 'world'
get '/', {}, 'flipper' => flipper
expect(flipper.adapter.cache).to be_empty
end
it 'clears the local cache even when the request raises an error' do
flipper.adapter.cache['hello'] = 'world'
begin
get '/fail', {}, 'flipper' => flipper
rescue
nil
end
expect(flipper.adapter.cache).to be_empty
end
it 'caches getting a feature for duration of request' do
flipper[:stats].enable
# clear the log of operations
adapter.reset
app = lambda do |_env|
flipper[:stats].enabled?
flipper[:stats].enabled?
flipper[:stats].enabled?
flipper[:stats].enabled?
flipper[:stats].enabled?
flipper[:stats].enabled?
[200, {}, []]
end
middleware = described_class.new(app)
middleware.call(env)
expect(adapter.count(:get)).to be(1)
end
end
context 'with preload: true' do
let(:app) do
# ensure scoped for builder block, annoying...
instance = flipper
middleware = described_class
Rack::Builder.new do
use middleware, preload: true
map '/' do
run ->(_env) { [200, {}, []] }
end
map '/fail' do
run ->(_env) { raise 'FAIL!' }
end
end.to_app
end
include_examples 'flipper middleware'
it 'eagerly caches known features for duration of request' do
flipper[:stats].enable
flipper[:shiny].enable
# clear the log of operations
adapter.reset
app = lambda do |_env|
flipper[:stats].enabled?
flipper[:stats].enabled?
flipper[:shiny].enabled?
flipper[:shiny].enabled?
[200, {}, []]
end
middleware = described_class.new(app, preload: true)
middleware.call(env)
expect(adapter.operations.size).to be(1)
expect(adapter.count(:get_all)).to be(1)
end
it 'caches unknown features for duration of request' do
# clear the log of operations
adapter.reset
app = lambda do |_env|
flipper[:other].enabled?
flipper[:other].enabled?
[200, {}, []]
end
middleware = described_class.new(app, preload: true)
middleware.call(env)
expect(adapter.count(:get)).to be(1)
expect(adapter.last(:get).args).to eq([flipper[:other]])
end
end
context 'with preload specific' do
let(:app) do
# ensure scoped for builder block, annoying...
instance = flipper
middleware = described_class
Rack::Builder.new do
use middleware, preload: %i(stats)
map '/' do
run ->(_env) { [200, {}, []] }
end
map '/fail' do
run ->(_env) { raise 'FAIL!' }
end
end.to_app
end
include_examples 'flipper middleware'
it 'eagerly caches specified features for duration of request' do
# clear the log of operations
adapter.reset
app = lambda do |_env|
flipper[:stats].enabled?
flipper[:stats].enabled?
flipper[:shiny].enabled?
flipper[:shiny].enabled?
[200, {}, []]
end
middleware = described_class.new app, preload: %i(stats)
middleware.call(env)
expect(adapter.count(:get_multi)).to be(1)
expect(adapter.last(:get_multi).args).to eq([[flipper[:stats]]])
end
it 'caches unknown features for duration of request' do
# clear the log of operations
adapter.reset
app = lambda do |_env|
flipper[:other].enabled?
flipper[:other].enabled?
[200, {}, []]
end
middleware = described_class.new app, preload: %i(stats)
middleware.call(env)
expect(adapter.count(:get)).to be(1)
expect(adapter.last(:get).args).to eq([flipper[:other]])
end
end
context 'with multiple instances' do
let(:app) do
# ensure scoped for builder block, annoying...
instance = flipper
middleware = described_class
Rack::Builder.new do
use middleware, preload: %i(stats)
# Second instance should be a noop
use middleware, preload: true
map '/' do
run ->(_env) { [200, {}, []] }
end
map '/fail' do
run ->(_env) { raise 'FAIL!' }
end
end.to_app
end
def get(uri, params = {}, env = {}, &block)
silence { super(uri, params, env, &block) }
end
include_examples 'flipper middleware'
it 'does not call preload in second instance' do
expect(flipper).not_to receive(:preload_all)
output = get '/', {}, 'flipper' => flipper
expect(output).to match(/Flipper::Middleware::Memoizer appears to be running twice/)
expect(adapter.count(:get_multi)).to be(1)
expect(adapter.last(:get_multi).args).to eq([[flipper[:stats]]])
end
end
context 'when an app raises an exception' do
it 'resets memoize' do
begin
app = ->(_env) { raise }
middleware = described_class.new(app)
middleware.call(env)
rescue RuntimeError
expect(flipper.memoizing?).to be(false)
end
end
end
context 'with flipper setup in env' do
let(:app) do
# ensure scoped for builder block, annoying...
instance = flipper
middleware = described_class
Rack::Builder.new do
use middleware
map '/' do
run ->(_env) { [200, {}, []] }
end
map '/fail' do
run ->(_env) { raise 'FAIL!' }
end
end.to_app
end
include_examples 'flipper middleware'
end
context 'with Flipper setup in env' do
it 'caches getting a feature for duration of request' do
Flipper.configure do |config|
config.adapter do
memory = Flipper::Adapters::Memory.new
Flipper::Adapters::OperationLogger.new(memory)
end
end
Flipper.enable(:stats)
Flipper.adapter.reset # clear the log of operations
app = lambda do |_env|
Flipper.enabled?(:stats)
Flipper.enabled?(:stats)
Flipper.enabled?(:stats)
[200, {}, []]
end
middleware = described_class.new(app)
middleware.call('flipper' => Flipper)
expect(Flipper.adapter.count(:get)).to be(1)
end
end
context 'defaults to Flipper' do
it 'caches getting a feature for duration of request' do
Flipper.configure do |config|
config.default do
memory_adapter = Flipper::Adapters::Memory.new
logged_adapter = Flipper::Adapters::OperationLogger.new(memory_adapter)
Flipper.new(logged_adapter)
end
end
Flipper.enable(:stats)
Flipper.adapter.reset # clear the log of operations
app = lambda do |_env|
Flipper.enabled?(:stats)
Flipper.enabled?(:stats)
Flipper.enabled?(:stats)
[200, {}, []]
end
middleware = described_class.new(app)
middleware.call({})
expect(Flipper.adapter.count(:get)).to be(1)
end
end
context 'with preload:true' do
let(:options) { {preload: true} }
let(:app) do
# ensure scoped for builder block, annoying...
middleware = described_class
opts = options
Rack::Builder.new do
use middleware, opts
map '/' do
run ->(_env) { [200, {}, []] }
end
map '/fail' do
run ->(_env) { raise 'FAIL!' }
end
end.to_app
end
context 'and unless option' do
before do
options[:unless] = ->(request) { request.path.start_with?("/assets") }
end
it 'does NOT preload if request matches unless block' do
expect(flipper).to receive(:preload_all).never
get '/assets/foo.png', {}, 'flipper' => flipper
end
it 'does preload if request does NOT match unless block' do
expect(flipper).to receive(:preload_all).once
get '/some/other/path', {}, 'flipper' => flipper
end
end
context 'and if option' do
before do
options[:if] = ->(request) { !request.path.start_with?("/assets") }
end
it 'does NOT preload if request does not match if block' do
expect(flipper).to receive(:preload_all).never
get '/assets/foo.png', {}, 'flipper' => flipper
end
it 'does preload if request matches if block' do
expect(flipper).to receive(:preload_all).once
get '/some/other/path', {}, 'flipper' => flipper
end
end
end
context 'with preload:true and caching adapter' do
let(:app) do
app = lambda do |_env|
flipper[:stats].enabled?
flipper[:stats].enabled?
flipper[:shiny].enabled?
flipper[:shiny].enabled?
[200, {}, []]
end
described_class.new(app, preload: true)
end
it 'eagerly caches known features for duration of request' do
memory = Flipper::Adapters::Memory.new
logged_memory = Flipper::Adapters::OperationLogger.new(memory)
cache = ActiveSupport::Cache::MemoryStore.new
cache.clear
cached = Flipper::Adapters::ActiveSupportCacheStore.new(logged_memory, cache, expires_in: 10)
logged_cached = Flipper::Adapters::OperationLogger.new(cached)
memo = {}
flipper = Flipper.new(logged_cached)
flipper[:stats].enable
flipper[:shiny].enable
# clear the log of operations
logged_memory.reset
logged_cached.reset
get '/', {}, 'flipper' => flipper
expect(logged_cached.count(:get_all)).to be(1)
expect(logged_memory.count(:get_all)).to be(1)
get '/', {}, 'flipper' => flipper
expect(logged_cached.count(:get_all)).to be(2)
expect(logged_memory.count(:get_all)).to be(1)
get '/', {}, 'flipper' => flipper
expect(logged_cached.count(:get_all)).to be(3)
expect(logged_memory.count(:get_all)).to be(1)
end
end
end
|
