debian-mirror-gitlab/spec/lib/gitlab/json_cache_spec.rb
2019-02-15 15:39:39 +05:30

401 lines
11 KiB
Ruby

# frozen_string_literal: true
require 'spec_helper'
describe Gitlab::JsonCache do
let(:backend) { double('backend').as_null_object }
let(:namespace) { 'geo' }
let(:key) { 'foo' }
let(:expanded_key) { "#{namespace}:#{key}:#{Rails.version}" }
let(:broadcast_message) { create(:broadcast_message) }
subject(:cache) { described_class.new(namespace: namespace, backend: backend) }
describe '#active?' do
context 'when backend respond to active? method' do
it 'delegates to the underlying cache implementation' do
backend = double('backend', active?: false)
cache = described_class.new(namespace: namespace, backend: backend)
expect(cache.active?).to eq(false)
end
end
context 'when backend does not respond to active? method' do
it 'returns true' do
backend = double('backend')
cache = described_class.new(namespace: namespace, backend: backend)
expect(cache.active?).to eq(true)
end
end
end
describe '#cache_key' do
context 'when namespace is not defined' do
it 'expands out the key with Rails version' do
cache = described_class.new(cache_key_with_version: true)
cache_key = cache.cache_key(key)
expect(cache_key).to eq("#{key}:#{Rails.version}")
end
end
context 'when cache_key_with_version is true' do
it 'expands out the key with namespace and Rails version' do
cache = described_class.new(namespace: namespace, cache_key_with_version: true)
cache_key = cache.cache_key(key)
expect(cache_key).to eq("#{namespace}:#{key}:#{Rails.version}")
end
end
context 'when cache_key_with_version is false' do
it 'expands out the key with namespace' do
cache = described_class.new(namespace: namespace, cache_key_with_version: false)
cache_key = cache.cache_key(key)
expect(cache_key).to eq("#{namespace}:#{key}")
end
end
context 'when namespace is nil, and cache_key_with_version is false' do
it 'returns the key' do
cache = described_class.new(namespace: nil, cache_key_with_version: false)
cache_key = cache.cache_key(key)
expect(cache_key).to eq(key)
end
end
end
describe '#expire' do
it 'expires the given key from the cache' do
cache.expire(key)
expect(backend).to have_received(:delete).with(expanded_key)
end
end
describe '#read' do
it 'reads the given key from the cache' do
cache.read(key)
expect(backend).to have_received(:read).with(expanded_key)
end
it 'returns the cached value when there is data in the cache with the given key' do
allow(backend).to receive(:read)
.with(expanded_key)
.and_return("true")
expect(cache.read(key)).to eq(true)
end
it 'returns nil when there is no data in the cache with the given key' do
allow(backend).to receive(:read)
.with(expanded_key)
.and_return(nil)
expect(cache.read(key)).to be_nil
end
context 'when the cached value is a hash' do
it 'parses the cached value' do
allow(backend).to receive(:read)
.with(expanded_key)
.and_return(broadcast_message.to_json)
expect(cache.read(key, BroadcastMessage)).to eq(broadcast_message)
end
it 'returns nil when klass is nil' do
allow(backend).to receive(:read)
.with(expanded_key)
.and_return(broadcast_message.to_json)
expect(cache.read(key)).to be_nil
end
it 'gracefully handles bad cached entry' do
allow(backend).to receive(:read)
.with(expanded_key)
.and_return('{')
expect(cache.read(key, BroadcastMessage)).to be_nil
end
it 'gracefully handles an empty hash' do
allow(backend).to receive(:read)
.with(expanded_key)
.and_return('{}')
expect(cache.read(key, BroadcastMessage)).to be_a(BroadcastMessage)
end
it 'gracefully handles unknown attributes' do
allow(backend).to receive(:read)
.with(expanded_key)
.and_return(broadcast_message.attributes.merge(unknown_attribute: 1).to_json)
expect(cache.read(key, BroadcastMessage)).to be_nil
end
end
context 'when the cached value is an array' do
it 'parses the cached value' do
allow(backend).to receive(:read)
.with(expanded_key)
.and_return([broadcast_message].to_json)
expect(cache.read(key, BroadcastMessage)).to eq([broadcast_message])
end
it 'returns an empty array when klass is nil' do
allow(backend).to receive(:read)
.with(expanded_key)
.and_return([broadcast_message].to_json)
expect(cache.read(key)).to eq([])
end
it 'gracefully handles bad cached entry' do
allow(backend).to receive(:read)
.with(expanded_key)
.and_return('[')
expect(cache.read(key, BroadcastMessage)).to be_nil
end
it 'gracefully handles an empty array' do
allow(backend).to receive(:read)
.with(expanded_key)
.and_return('[]')
expect(cache.read(key, BroadcastMessage)).to eq([])
end
it 'gracefully handles unknown attributes' do
allow(backend).to receive(:read)
.with(expanded_key)
.and_return([{ unknown_attribute: 1 }, broadcast_message.attributes].to_json)
expect(cache.read(key, BroadcastMessage)).to eq([broadcast_message])
end
end
end
describe '#write' do
it 'writes value to the cache with the given key' do
cache.write(key, true)
expect(backend).to have_received(:write).with(expanded_key, "true", nil)
end
it 'writes a string containing a JSON representation of the value to the cache' do
cache.write(key, broadcast_message)
expect(backend).to have_received(:write)
.with(expanded_key, broadcast_message.to_json, nil)
end
it 'passes options the underlying cache implementation' do
cache.write(key, true, expires_in: 15.seconds)
expect(backend).to have_received(:write)
.with(expanded_key, "true", expires_in: 15.seconds)
end
it 'passes options the underlying cache implementation when options is empty' do
cache.write(key, true, {})
expect(backend).to have_received(:write)
.with(expanded_key, "true", {})
end
it 'passes options the underlying cache implementation when options is nil' do
cache.write(key, true, nil)
expect(backend).to have_received(:write)
.with(expanded_key, "true", nil)
end
end
describe '#fetch', :use_clean_rails_memory_store_caching do
let(:backend) { Rails.cache }
it 'requires a block' do
expect { cache.fetch(key) }.to raise_error(LocalJumpError)
end
it 'passes options the underlying cache implementation' do
expect(backend).to receive(:write)
.with(expanded_key, "true", expires_in: 15.seconds)
cache.fetch(key, expires_in: 15.seconds) { true }
end
context 'when the given key does not exist in the cache' do
context 'when the result of the block is truthy' do
it 'returns the result of the block' do
result = cache.fetch(key) { true }
expect(result).to eq(true)
end
it 'caches the value' do
expect(backend).to receive(:write).with(expanded_key, "true", {})
cache.fetch(key) { true }
end
end
context 'when the result of the block is false' do
it 'returns the result of the block' do
result = cache.fetch(key) { false }
expect(result).to eq(false)
end
it 'caches the value' do
expect(backend).to receive(:write).with(expanded_key, "false", {})
cache.fetch(key) { false }
end
end
context 'when the result of the block is nil' do
it 'returns the result of the block' do
result = cache.fetch(key) { nil }
expect(result).to eq(nil)
end
it 'caches the value' do
expect(backend).to receive(:write).with(expanded_key, "null", {})
cache.fetch(key) { nil }
end
end
end
context 'when the given key exists in the cache' do
context 'when the cached value is a hash' do
before do
backend.write(expanded_key, broadcast_message.to_json)
end
it 'parses the cached value' do
result = cache.fetch(key, as: BroadcastMessage) { 'block result' }
expect(result).to eq(broadcast_message)
end
it "returns the result of the block when 'as' option is nil" do
result = cache.fetch(key, as: nil) { 'block result' }
expect(result).to eq('block result')
end
it "returns the result of the block when 'as' option is not informed" do
result = cache.fetch(key) { 'block result' }
expect(result).to eq('block result')
end
end
context 'when the cached value is a array' do
before do
backend.write(expanded_key, [broadcast_message].to_json)
end
it 'parses the cached value' do
result = cache.fetch(key, as: BroadcastMessage) { 'block result' }
expect(result).to eq([broadcast_message])
end
it "returns an empty array when 'as' option is nil" do
result = cache.fetch(key, as: nil) { 'block result' }
expect(result).to eq([])
end
it "returns an empty array when 'as' option is not informed" do
result = cache.fetch(key) { 'block result' }
expect(result).to eq([])
end
end
context 'when the cached value is true' do
before do
backend.write(expanded_key, "true")
end
it 'returns the cached value' do
result = cache.fetch(key) { 'block result' }
expect(result).to eq(true)
end
it 'does not execute the block' do
expect { |block| cache.fetch(key, &block) }.not_to yield_control
end
it 'does not write to the cache' do
expect(backend).not_to receive(:write)
cache.fetch(key) { 'block result' }
end
end
context 'when the cached value is false' do
before do
backend.write(expanded_key, "false")
end
it 'returns the cached value' do
result = cache.fetch(key) { 'block result' }
expect(result).to eq(false)
end
it 'does not execute the block' do
expect { |block| cache.fetch(key, &block) }.not_to yield_control
end
it 'does not write to the cache' do
expect(backend).not_to receive(:write)
cache.fetch(key) { 'block result' }
end
end
context 'when the cached value is nil' do
before do
backend.write(expanded_key, "null")
end
it 'returns the result of the block' do
result = cache.fetch(key) { 'block result' }
expect(result).to eq('block result')
end
it 'writes the result of the block to the cache' do
expect(backend).to receive(:write)
.with(expanded_key, 'block result'.to_json, {})
cache.fetch(key) { 'block result' }
end
end
end
end
end