active_model_serializers/test/cache_test.rb

# frozen_string_literal: true

require 'test_helper'
require 'tmpdir'
require 'tempfile'

module ActiveModelSerializers
  class CacheTest < ActiveSupport::TestCase
    class Article < ::Model
      attributes :title
      # To confirm error is raised when cache_key is not set and cache_key option not passed to cache
      undef_method :cache_key
    end
    class ArticleSerializer < ActiveModel::Serializer
      cache only: [:place], skip_digest: true
      attributes :title
    end

    class Author < ::Model
      attributes :id, :name
      associations :posts, :bio, :roles
    end
    # Instead of a primitive cache key (i.e. a string), this class
    # returns a list of objects that require to be expanded themselves.
    class AuthorWithExpandableCacheElements < Author
      # For the test purposes it's important that #to_s for HasCacheKey differs
      # between instances, hence not a Struct.
      class HasCacheKey
        attr_reader :cache_key
        def initialize(cache_key)
          @cache_key = cache_key
        end

        def to_s
          "HasCacheKey##{object_id}"
        end
      end

      def cache_key
        [
          HasCacheKey.new(name),
          HasCacheKey.new(id)
        ]
      end
    end
    class UncachedAuthor < Author
      # To confirm cache_key is set using updated_at and cache_key option passed to cache
      undef_method :cache_key
    end
    class AuthorSerializer < ActiveModel::Serializer
      cache key: 'writer', skip_digest: true
      attributes :id, :name

      has_many :posts
      has_many :roles
      has_one :bio
    end

    class Blog < ::Model
      attributes :name
      associations :writer
    end
    class BlogSerializer < ActiveModel::Serializer
      cache key: 'blog'
      attributes :id, :name

      belongs_to :writer
    end

    class Comment < ::Model
      attributes :id, :body
      associations :post, :author

      # Uses a custom non-time-based cache key
      def cache_key
        "comment/#{id}"
      end
    end
    class CommentSerializer < ActiveModel::Serializer
      cache expires_in: 1.day, skip_digest: true
      attributes :id, :body
      belongs_to :post
      belongs_to :author
    end

    class Post < ::Model
      attributes :id, :title, :body
      associations :author, :comments, :blog
    end
    class PostSerializer < ActiveModel::Serializer
      cache key: 'post', expires_in: 0.1, skip_digest: true
      attributes :id, :title, :body

      has_many :comments
      belongs_to :blog
      belongs_to :author
    end

    class Role < ::Model
      attributes :name, :description, :special_attribute
      associations :author
    end
    class RoleSerializer < ActiveModel::Serializer
      cache only: [:name, :slug], skip_digest: true
      attributes :id, :name, :description
      attribute :friendly_id, key: :slug
      belongs_to :author

      def friendly_id
        "#{object.name}-#{object.id}"
      end
    end
    class InheritedRoleSerializer < RoleSerializer
      cache key: 'inherited_role', only: [:name, :special_attribute]
      attribute :special_attribute
    end

    setup do
      cache_store.clear
      @comment        = Comment.new(id: 1, body: 'ZOMG A COMMENT')
      @post           = Post.new(id: 'post', title: 'New Post', body: 'Body')
      @bio            = Bio.new(id: 1, content: 'AMS Contributor')
      @author         = Author.new(id: 'author', name: 'Joao M. D. Moura')
      @blog           = Blog.new(id: 999, name: 'Custom blog', writer: @author)
      @role           = Role.new(name: 'Great Author')
      @location       = Location.new(lat: '-23.550520', lng: '-46.633309')
      @place          = Place.new(name: 'Amazing Place')
      @author.posts   = [@post]
      @author.roles   = [@role]
      @role.author    = @author
      @author.bio     = @bio
      @bio.author     = @author
      @post.comments  = [@comment]
      @post.author    = @author
      @comment.post   = @post
      @comment.author = @author
      @post.blog      = @blog
      @location.place = @place

      @location_serializer = LocationSerializer.new(@location)
      @bio_serializer      = BioSerializer.new(@bio)
      @role_serializer     = RoleSerializer.new(@role)
      @post_serializer     = PostSerializer.new(@post)
      @author_serializer   = AuthorSerializer.new(@author)
      @comment_serializer  = CommentSerializer.new(@comment)
      @blog_serializer     = BlogSerializer.new(@blog)
    end

    def test_explicit_cache_store
      default_store = Class.new(ActiveModel::Serializer) do
        cache
      end
      explicit_store = Class.new(ActiveModel::Serializer) do
        cache cache_store: ActiveSupport::Cache::FileStore
      end

      assert ActiveSupport::Cache::MemoryStore, ActiveModelSerializers.config.cache_store
      assert ActiveSupport::Cache::MemoryStore, default_store.cache_store
      assert ActiveSupport::Cache::FileStore, explicit_store.cache_store
    end

    def test_inherited_cache_configuration
      inherited_serializer = Class.new(PostSerializer)

      assert_equal PostSerializer._cache_key, inherited_serializer._cache_key
      assert_equal PostSerializer._cache_options, inherited_serializer._cache_options
    end

    def test_override_cache_configuration
      inherited_serializer = Class.new(PostSerializer) do
        cache key: 'new-key'
      end

      assert_equal PostSerializer._cache_key, 'post'
      assert_equal inherited_serializer._cache_key, 'new-key'
    end

    def test_cache_definition
      assert_equal(cache_store, @post_serializer.class._cache)
      assert_equal(cache_store, @author_serializer.class._cache)
      assert_equal(cache_store, @comment_serializer.class._cache)
    end

    def test_cache_key_definition
      assert_equal('post', @post_serializer.class._cache_key)
      assert_equal('writer', @author_serializer.class._cache_key)
      assert_nil(@comment_serializer.class._cache_key)
    end

    def test_cache_key_interpolation_with_updated_at_when_cache_key_is_not_defined_on_object
      uncached_author            = UncachedAuthor.new(name: 'Joao M. D. Moura')
      uncached_author_serializer = AuthorSerializer.new(uncached_author)

      render_object_with_cache(uncached_author)
      key = "#{uncached_author_serializer.class._cache_key}/#{uncached_author_serializer.object.id}-#{uncached_author_serializer.object.updated_at.strftime('%Y%m%d%H%M%S%9N')}"
      key = "#{key}/#{adapter.cache_key}"
      assert_equal(uncached_author_serializer.attributes.to_json, cache_store.fetch(key).to_json)
    end

    def test_cache_key_expansion
      author = AuthorWithExpandableCacheElements.new(id: 10, name: 'hello')
      same_author = AuthorWithExpandableCacheElements.new(id: 10, name: 'hello')
      diff_author = AuthorWithExpandableCacheElements.new(id: 11, name: 'hello')

      author_serializer = AuthorSerializer.new(author)
      same_author_serializer = AuthorSerializer.new(same_author)
      diff_author_serializer = AuthorSerializer.new(diff_author)
      adapter = AuthorSerializer.serialization_adapter_instance

      assert_equal(author_serializer.cache_key(adapter), same_author_serializer.cache_key(adapter))
      refute_equal(author_serializer.cache_key(adapter), diff_author_serializer.cache_key(adapter))
    end

    def test_default_cache_key_fallback
      render_object_with_cache(@comment)
      key = "#{@comment.cache_key}/#{adapter.cache_key}"
      assert_equal(@comment_serializer.attributes.to_json, cache_store.fetch(key).to_json)
    end

    def test_error_is_raised_if_cache_key_is_not_defined_on_object_or_passed_as_cache_option
      article = Article.new(title: 'Must Read')
      e = assert_raises ActiveModel::Serializer::UndefinedCacheKey do
        render_object_with_cache(article)
      end
      assert_match(/ActiveModelSerializers::CacheTest::Article must define #cache_key, or the 'key:' option must be passed into 'ActiveModelSerializers::CacheTest::ArticleSerializer.cache'/, e.message)
    end

    def test_cache_options_definition
      assert_equal({ expires_in: 0.1, skip_digest: true }, @post_serializer.class._cache_options)
      assert_nil(@blog_serializer.class._cache_options)
      assert_equal({ expires_in: 1.day, skip_digest: true }, @comment_serializer.class._cache_options)
    end

    def test_fragment_cache_definition
      assert_equal([:name, :slug], @role_serializer.class._cache_only)
      assert_equal([:content], @bio_serializer.class._cache_except)
    end

    def test_associations_separately_cache
      cache_store.clear
      assert_nil(cache_store.fetch(@post.cache_key))
      assert_nil(cache_store.fetch(@comment.cache_key))

      Timecop.freeze(Time.current) do
        render_object_with_cache(@post)

        key = "#{@post.cache_key}/#{adapter.cache_key}"
        assert_equal(@post_serializer.attributes, cache_store.fetch(key))
        key = "#{@comment.cache_key}/#{adapter.cache_key}"
        assert_equal(@comment_serializer.attributes, cache_store.fetch(key))
      end
    end

    def test_associations_cache_when_updated
      Timecop.freeze(Time.current) do
        # Generate a new Cache of Post object and each objects related to it.
        render_object_with_cache(@post)

        # Check if it cached the objects separately
        key = "#{@post.cache_key}/#{adapter.cache_key}"
        assert_equal(@post_serializer.attributes, cache_store.fetch(key))
        key = "#{@comment.cache_key}/#{adapter.cache_key}"
        assert_equal(@comment_serializer.attributes, cache_store.fetch(key))

        # Simulating update on comments relationship with Post
        new_comment            = Comment.new(id: 2567, body: 'ZOMG A NEW COMMENT')
        new_comment_serializer = CommentSerializer.new(new_comment)
        @post.comments         = [new_comment]

        # Ask for the serialized object
        render_object_with_cache(@post)

        # Check if the the new comment was cached
        key = "#{new_comment.cache_key}/#{adapter.cache_key}"
        assert_equal(new_comment_serializer.attributes, cache_store.fetch(key))
        key = "#{@post.cache_key}/#{adapter.cache_key}"
        assert_equal(@post_serializer.attributes, cache_store.fetch(key))
      end
    end

    def test_fragment_fetch_with_virtual_associations
      expected_result = {
        id: @location.id,
        lat: @location.lat,
        lng: @location.lng,
        address: 'Nowhere'
      }

      hash = render_object_with_cache(@location)

      assert_equal(hash, expected_result)
      key = "#{@location.cache_key}/#{adapter.cache_key}"
      assert_equal({ address: 'Nowhere' }, cache_store.fetch(key))
    end

    def test_fragment_cache_with_inheritance
      inherited = render_object_with_cache(@role, serializer: InheritedRoleSerializer)
      base = render_object_with_cache(@role)

      assert_includes(inherited.keys, :special_attribute)
      refute_includes(base.keys, :special_attribute)
    end

    def test_uses_adapter_in_cache_key
      render_object_with_cache(@post)
      key = "#{@post.cache_key}/#{adapter.class.to_s.demodulize.underscore}"
      assert_equal(@post_serializer.attributes, cache_store.fetch(key))
    end

    # Based on original failing test by @kevintyll
    # rubocop:disable Metrics/AbcSize
    def test_a_serializer_rendered_by_two_adapter_returns_differently_fetch_attributes
      Object.const_set(:Alert, Class.new(ActiveModelSerializers::Model) do
        attributes :id, :status, :resource, :started_at, :ended_at, :updated_at, :created_at
      end)
      Object.const_set(:UncachedAlertSerializer, Class.new(ActiveModel::Serializer) do
        attributes :id, :status, :resource, :started_at, :ended_at, :updated_at, :created_at
      end)
      Object.const_set(:AlertSerializer, Class.new(UncachedAlertSerializer) do
        cache
      end)

      alert = Alert.new(
        id: 1,
        status: 'fail',
        resource: 'resource-1',
        started_at: Time.new(2016, 3, 31, 21, 36, 35, 0),
        ended_at: nil,
        updated_at: Time.new(2016, 3, 31, 21, 27, 35, 0),
        created_at: Time.new(2016, 3, 31, 21, 37, 35, 0)
      )

      expected_fetch_attributes = {
        id: 1,
        status: 'fail',
        resource: 'resource-1',
        started_at: alert.started_at,
        ended_at: nil,
        updated_at: alert.updated_at,
        created_at: alert.created_at
      }.with_indifferent_access
      expected_cached_jsonapi_attributes = {
        id: '1',
        type: 'alerts',
        attributes: {
          status: 'fail',
          resource: 'resource-1',
          started_at: alert.started_at,
          ended_at: nil,
          updated_at: alert.updated_at,
          created_at: alert.created_at
        }
      }.with_indifferent_access

      # Assert attributes are serialized correctly
      serializable_alert = serializable(alert, serializer: AlertSerializer, adapter: :attributes)
      attributes_serialization = serializable_alert.as_json.with_indifferent_access
      assert_equal expected_fetch_attributes, alert.attributes
      assert_equal alert.attributes, attributes_serialization
      attributes_cache_key = serializable_alert.adapter.serializer.cache_key(serializable_alert.adapter)
      assert_equal attributes_serialization, cache_store.fetch(attributes_cache_key).with_indifferent_access

      serializable_alert = serializable(alert, serializer: AlertSerializer, adapter: :json_api)
      jsonapi_cache_key = serializable_alert.adapter.serializer.cache_key(serializable_alert.adapter)
      # Assert cache keys differ
      refute_equal attributes_cache_key, jsonapi_cache_key
      # Assert (cached) serializations differ
      jsonapi_serialization = serializable_alert.as_json
      assert_equal alert.status, jsonapi_serialization.fetch(:data).fetch(:attributes).fetch(:status)
      serializable_alert = serializable(alert, serializer: UncachedAlertSerializer, adapter: :json_api)
      assert_equal serializable_alert.as_json, jsonapi_serialization

      cached_serialization = cache_store.fetch(jsonapi_cache_key).with_indifferent_access
      assert_equal expected_cached_jsonapi_attributes, cached_serialization
    ensure
      Object.send(:remove_const, :Alert)
      Object.send(:remove_const, :AlertSerializer)
      Object.send(:remove_const, :UncachedAlertSerializer)
    end
    # rubocop:enable Metrics/AbcSize

    def test_uses_file_digest_in_cache_key
      render_object_with_cache(@blog)
      file_digest = Digest::MD5.hexdigest(File.open(__FILE__).read)
      key = "#{@blog.cache_key}/#{adapter.cache_key}/#{file_digest}"
      assert_equal(@blog_serializer.attributes, cache_store.fetch(key))
    end

    def test_cache_digest_definition
      file_digest = Digest::MD5.hexdigest(File.open(__FILE__).read)
      assert_equal(file_digest, @post_serializer.class._cache_digest)
    end

    def test_object_cache_keys
      serializable = ActiveModelSerializers::SerializableResource.new([@comment, @comment])
      include_directive = JSONAPI::IncludeDirective.new('*', allow_wildcard: true)

      actual = ActiveModel::Serializer.object_cache_keys(serializable.adapter.serializer, serializable.adapter, include_directive)

      assert_equal 3, actual.size
      expected_key = "comment/1/#{serializable.adapter.cache_key}"
      assert actual.any? { |key| key == expected_key }, "actual '#{actual}' should include #{expected_key}"
      expected_key = %r{post/post-\d+}
      assert actual.any? { |key| key =~ expected_key }, "actual '#{actual}' should match '#{expected_key}'"
      expected_key = %r{author/author-\d+}
      assert actual.any? { |key| key =~ expected_key }, "actual '#{actual}' should match '#{expected_key}'"
    end

    # rubocop:disable Metrics/AbcSize
    def test_fetch_attributes_from_cache
      serializers = ActiveModel::Serializer::CollectionSerializer.new([@comment, @comment])

      Timecop.freeze(Time.current) do
        render_object_with_cache(@comment)

        options = {}
        adapter_options = {}
        adapter_instance = ActiveModelSerializers::Adapter::Attributes.new(serializers, adapter_options)
        serializers.serializable_hash(adapter_options, options, adapter_instance)
        cached_attributes = options.fetch(:cached_attributes).with_indifferent_access

        include_directive = ActiveModelSerializers.default_include_directive
        manual_cached_attributes = ActiveModel::Serializer.cache_read_multi(serializers, adapter_instance, include_directive).with_indifferent_access
        assert_equal manual_cached_attributes, cached_attributes

        assert_equal cached_attributes["#{@comment.cache_key}/#{adapter_instance.cache_key}"], Comment.new(id: 1, body: 'ZOMG A COMMENT').attributes
        assert_equal cached_attributes["#{@comment.post.cache_key}/#{adapter_instance.cache_key}"], Post.new(id: 'post', title: 'New Post', body: 'Body').attributes

        writer = @comment.post.blog.writer
        writer_cache_key = writer.cache_key
        assert_equal cached_attributes["#{writer_cache_key}/#{adapter_instance.cache_key}"], Author.new(id: 'author', name: 'Joao M. D. Moura').attributes
      end
    end
    # rubocop:enable Metrics/AbcSize

    def test_cache_read_multi_with_fragment_cache_enabled
      post_serializer = Class.new(ActiveModel::Serializer) do
        cache except: [:body]
      end

      serializers = ActiveModel::Serializer::CollectionSerializer.new([@post, @post], serializer: post_serializer)

      Timecop.freeze(Time.current) do
        # Warming up.
        options = {}
        adapter_options = {}
        adapter_instance = ActiveModelSerializers::Adapter::Attributes.new(serializers, adapter_options)
        serializers.serializable_hash(adapter_options, options, adapter_instance)

        # Should find something with read_multi now
        options = {}
        serializers.serializable_hash(adapter_options, options, adapter_instance)
        cached_attributes = options.fetch(:cached_attributes)

        include_directive = ActiveModelSerializers.default_include_directive
        manual_cached_attributes = ActiveModel::Serializer.cache_read_multi(serializers, adapter_instance, include_directive)

        refute_equal 0, cached_attributes.size
        refute_equal 0, manual_cached_attributes.size
        assert_equal manual_cached_attributes, cached_attributes
      end
    end

    def test_serializer_file_path_on_nix
      path = '/Users/git/emberjs/ember-crm-backend/app/serializers/lead_serializer.rb'
      caller_line = "#{path}:1:in `<top (required)>'"
      assert_equal caller_line[ActiveModel::Serializer::CALLER_FILE], path
    end

    def test_serializer_file_path_on_windows
      path = 'c:/git/emberjs/ember-crm-backend/app/serializers/lead_serializer.rb'
      caller_line = "#{path}:1:in `<top (required)>'"
      assert_equal caller_line[ActiveModel::Serializer::CALLER_FILE], path
    end

    def test_serializer_file_path_with_space
      path = '/Users/git/ember js/ember-crm-backend/app/serializers/lead_serializer.rb'
      caller_line = "#{path}:1:in `<top (required)>'"
      assert_equal caller_line[ActiveModel::Serializer::CALLER_FILE], path
    end

    def test_serializer_file_path_with_submatch
      # The submatch in the path ensures we're using a correctly greedy regexp.
      path = '/Users/git/ember js/ember:123:in x/app/serializers/lead_serializer.rb'
      caller_line = "#{path}:1:in `<top (required)>'"
      assert_equal caller_line[ActiveModel::Serializer::CALLER_FILE], path
    end

    def test_digest_caller_file
      contents = "puts 'AMS rocks'!"
      dir = Dir.mktmpdir('space char')
      file = Tempfile.new('some_ruby.rb', dir)
      file.write(contents)
      path = file.path
      caller_line = "#{path}:1:in `<top (required)>'"
      file.close
      assert_equal ActiveModel::Serializer.digest_caller_file(caller_line), Digest::MD5.hexdigest(contents)
    ensure
      file.unlink
      FileUtils.remove_entry dir
    end

    def test_warn_on_serializer_not_defined_in_file
      called = false
      serializer = Class.new(ActiveModel::Serializer)
      assert_output(nil, /_cache_digest/) do
        serializer.digest_caller_file('')
        called = true
      end
      assert called
    end

    def test_cached_false_without_cache_store
      cached_serializer = build_cached_serializer do |serializer|
        serializer._cache = nil
      end
      refute cached_serializer.class.cache_enabled?
    end

    def test_cached_true_with_cache_store_and_without_cache_only_and_cache_except
      cached_serializer = build_cached_serializer do |serializer|
        serializer._cache = Object
      end
      assert cached_serializer.class.cache_enabled?
    end

    def test_cached_false_with_cache_store_and_with_cache_only
      cached_serializer = build_cached_serializer do |serializer|
        serializer._cache = Object
        serializer._cache_only = [:name]
      end
      refute cached_serializer.class.cache_enabled?
    end

    def test_cached_false_with_cache_store_and_with_cache_except
      cached_serializer = build_cached_serializer do |serializer|
        serializer._cache = Object
        serializer._cache_except = [:content]
      end
      refute cached_serializer.class.cache_enabled?
    end

    def test_fragment_cached_false_without_cache_store
      cached_serializer = build_cached_serializer do |serializer|
        serializer._cache = nil
        serializer._cache_only = [:name]
      end
      refute cached_serializer.class.fragment_cache_enabled?
    end

    def test_fragment_cached_true_with_cache_store_and_cache_only
      cached_serializer = build_cached_serializer do |serializer|
        serializer._cache = Object
        serializer._cache_only = [:name]
      end
      assert cached_serializer.class.fragment_cache_enabled?
    end

    def test_fragment_cached_true_with_cache_store_and_cache_except
      cached_serializer = build_cached_serializer do |serializer|
        serializer._cache = Object
        serializer._cache_except = [:content]
      end
      assert cached_serializer.class.fragment_cache_enabled?
    end

    def test_fragment_cached_false_with_cache_store_and_cache_except_and_cache_only
      cached_serializer = build_cached_serializer do |serializer|
        serializer._cache = Object
        serializer._cache_except = [:content]
        serializer._cache_only = [:name]
      end
      refute cached_serializer.class.fragment_cache_enabled?
    end

    def test_fragment_fetch_with_virtual_attributes
      author          = Author.new(name: 'Joao M. D. Moura')
      role            = Role.new(name: 'Great Author', description: nil)
      role.author     = [author]
      role_serializer = RoleSerializer.new(role)
      adapter_instance = ActiveModelSerializers::Adapter.configured_adapter.new(role_serializer)
      expected_result = {
        id: role.id,
        description: role.description,
        slug: "#{role.name}-#{role.id}",
        name: role.name
      }
      cache_store.clear

      role_hash = role_serializer.fetch_attributes_fragment(adapter_instance)
      assert_equal(role_hash, expected_result)

      role.id = 'this has been updated'
      role.name = 'this was cached'

      role_hash = role_serializer.fetch_attributes_fragment(adapter_instance)
      assert_equal(expected_result.merge(id: role.id), role_hash)
    end

    def test_fragment_fetch_with_except
      adapter_instance = ActiveModelSerializers::Adapter.configured_adapter.new(@bio_serializer)
      expected_result = {
        id: @bio.id,
        rating: nil,
        content: @bio.content
      }
      cache_store.clear

      bio_hash = @bio_serializer.fetch_attributes_fragment(adapter_instance)
      assert_equal(expected_result, bio_hash)

      @bio.content = 'this has been updated'
      @bio.rating = 'this was cached'

      bio_hash = @bio_serializer.fetch_attributes_fragment(adapter_instance)
      assert_equal(expected_result.merge(content: @bio.content), bio_hash)
    end

    def test_fragment_fetch_with_namespaced_object
      @spam            = Spam::UnrelatedLink.new(id: 'spam-id-1')
      @spam_serializer = Spam::UnrelatedLinkSerializer.new(@spam)
      adapter_instance = ActiveModelSerializers::Adapter.configured_adapter.new(@spam_serializer)
      @spam_hash       = @spam_serializer.fetch_attributes_fragment(adapter_instance)
      expected_result = {
        id: @spam.id
      }
      assert_equal(@spam_hash, expected_result)
    end

    private

    def cache_store
      ActiveModelSerializers.config.cache_store
    end

    def build_cached_serializer
      serializer = Class.new(ActiveModel::Serializer)
      serializer._cache_key = nil
      serializer._cache_options = nil
      yield serializer if block_given?
      serializer.new(Object)
    end

    def render_object_with_cache(obj, options = {})
      @serializable_resource = serializable(obj, options)
      @serializable_resource.serializable_hash
    end

    def adapter
      @serializable_resource.adapter
    end
  end
end