Merge pull request #342 from Netflix/release-1.5

Release 1.5

Author: shishirmk

README.md

@@ -221,7 +221,7 @@ end
 ```
 
 ### Links Per Object
-Links are defined in FastJsonapi using the `link` method. By default, link are read directly from the model property of the same name. In this example, `public_url` is expected to be a property of the object being serialized.
+Links are defined in FastJsonapi using the `link` method. By default, links are read directly from the model property of the same name. In this example, `public_url` is expected to be a property of the object being serialized.
 
 You can configure the method to use on the object for example a link with key `self` will get set to the value returned by a method called `url` on the movie object.
 
@@ -245,15 +245,38 @@ class MovieSerializer
 end
 ```
 
-### Meta Per Resource
-
-For every resource in the collection, you can include a meta object containing non-standard meta-information about a resource that can not be represented as an attribute or relationship.
+#### Links on a Relationship
 
+You can specify [relationship links](http://jsonapi.org/format/#document-resource-object-relationships) by using the `links:` option on the serializer. Relationship links in JSON API are useful if you want to load a parent document and then load associated documents later due to size constraints (see [related resource links](http://jsonapi.org/format/#document-resource-object-related-resource-links))
 
 ```ruby
 class MovieSerializer
   include FastJsonapi::ObjectSerializer
 
+  has_many :actors, links: {
+    self: :url,
+    related: -> (object) {
+      "https://movies.com/#{object.id}/actors"
+    }
+  }
+end
+```
+
+This will create a `self` reference for the relationship, and a `related` link for loading the actors relationship later. NB: This will not automatically disable loading the data in the relationship, you'll need to do that using the `lazy_load_data` option:
+
+```ruby
+  has_many :actors, lazy_load_data: true, links: {
+    self: :url,
+    related: -> (object) {
+      "https://movies.com/#{object.id}/actors"
+    }
+  }
+```
+
+### Meta Per Resource
+
+For every resource in the collection, you can include a meta object containing non-standard meta-information about a resource that can not be represented as an attribute or relationship.
+```ruby
   meta do |movie|
     {
       years_since_release: Date.current.year - movie.year
@@ -427,9 +450,9 @@ Option | Purpose | Example
 ------------ | ------------- | -------------
 set_type | Type name of Object | ```set_type :movie ```
 key | Key of Object | ```belongs_to :owner, key: :user ```
-set_id | ID of Object | ```set_id :owner_id ```
+set_id | ID of Object | ```set_id :owner_id ``` or ```set_id { |record| "#{record.name.downcase}-#{record.id}" }```
 cache_options | Hash to enable caching and set cache length | ```cache_options enabled: true, cache_length: 12.hours, race_condition_ttl: 10.seconds```
-id_method_name | Set custom method name to get ID of an object | ```has_many :locations, id_method_name: :place_ids ```
+id_method_name | Set custom method name to get ID of an object (If block is provided for the relationship, `id_method_name` is invoked on the return value of the block instead of the resource object) | ```has_many :locations, id_method_name: :place_ids ```
 object_method_name | Set custom method name to get related objects | ```has_many :locations, object_method_name: :places ```
 record_type | Set custom Object Type for a relationship | ```belongs_to :owner, record_type: :user```
 serializer | Set custom Serializer for a relationship | ```has_many :actors, serializer: :custom_actor``` or ```has_many :actors, serializer: MyApp::Api::V1::ActorSerializer```

lib/fast_jsonapi/object_serializer.rb

@@ -1,8 +1,10 @@
 # frozen_string_literal: true
 
+require 'active_support/time'
 require 'active_support/json'
 require 'active_support/concern'
 require 'active_support/inflector'
+require 'active_support/core_ext/numeric/time'
 require 'fast_jsonapi/attribute'
 require 'fast_jsonapi/relationship'
 require 'fast_jsonapi/link'
@@ -72,6 +74,7 @@ def serialized_json
 
     def process_options(options)
       @fieldsets = deep_symbolize(options[:fields].presence || {})
+      @params = {}
 
       return if options.blank?
 
@@ -117,7 +120,7 @@ def inherited(subclass)
         subclass.transform_method = transform_method
         subclass.cache_length = cache_length
         subclass.race_condition_ttl = race_condition_ttl
-        subclass.data_links = data_links
+        subclass.data_links = data_links.dup if data_links.present?
         subclass.cached = cached
         subclass.set_type(subclass.reflected_record_type) if subclass.reflected_record_type
         subclass.meta_to_serialize = meta_to_serialize
@@ -143,7 +146,11 @@ def set_key_transform(transform_name)
         self.transform_method = mapping[transform_name.to_sym]
 
         # ensure that the record type is correctly transformed
-        set_type(reflected_record_type) if reflected_record_type
+        if record_type
+          set_type(record_type)
+        elsif reflected_record_type
+          set_type(reflected_record_type)
+        end
       end
 
       def run_key_transform(input)
@@ -163,8 +170,8 @@ def set_type(type_name)
         self.record_type = run_key_transform(type_name)
       end
 
-      def set_id(id_name)
-        self.record_id = id_name
+      def set_id(id_name = nil, &block)
+        self.record_id = block || id_name
       end
 
       def cache_options(cache_options)
@@ -250,7 +257,9 @@ def create_relationship(base_key, relationship_type, options, block)
           cached: options[:cached],
           polymorphic: fetch_polymorphic_option(options),
           conditional_proc: options[:if],
-          transform_method: @transform_method
+          transform_method: @transform_method,
+          links: options[:links],
+          lazy_load_data: options[:lazy_load_data]
         )
       end
 

lib/fast_jsonapi/relationship.rb

@@ -1,6 +1,6 @@
 module FastJsonapi
   class Relationship
-    attr_reader :key, :name, :id_method_name, :record_type, :object_method_name, :object_block, :serializer, :relationship_type, :cached, :polymorphic, :conditional_proc, :transform_method
+    attr_reader :key, :name, :id_method_name, :record_type, :object_method_name, :object_block, :serializer, :relationship_type, :cached, :polymorphic, :conditional_proc, :transform_method, :links, :lazy_load_data
 
     def initialize(
       key:,
@@ -14,7 +14,9 @@ def initialize(
       cached: false,
       polymorphic:,
       conditional_proc:,
-      transform_method:
+      transform_method:,
+      links:,
+      lazy_load_data: false
     )
       @key = key
       @name = name
@@ -28,14 +30,19 @@ def initialize(
       @polymorphic = polymorphic
       @conditional_proc = conditional_proc
       @transform_method = transform_method
+      @links = links || {}
+      @lazy_load_data = lazy_load_data
     end
 
     def serialize(record, serialization_params, output_hash)
       if include_relationship?(record, serialization_params)
         empty_case = relationship_type == :has_many ? [] : nil
-        output_hash[key] = {
-          data: ids_hash_from_record_and_relationship(record, serialization_params) || empty_case
-        }
+
+        output_hash[key] = {}
+        unless lazy_load_data
+          output_hash[key][:data] = ids_hash_from_record_and_relationship(record, serialization_params) || empty_case
+        end
+        add_links_hash(record, serialization_params, output_hash) if links.present?
       end
     end
 
@@ -96,6 +103,12 @@ def fetch_id(record, params)
       record.public_send(id_method_name)
     end
 
+    def add_links_hash(record, params, output_hash)
+      output_hash[key][:links] = links.each_with_object({}) do |(key, method), hash|
+        Link.new(key: key, method: method).serialize(record, params, hash)\
+      end
+    end
+
     def run_key_transform(input)
       if self.transform_method.present?
         input.to_s.send(*self.transform_method).to_sym

lib/fast_jsonapi/serialization_core.rb

@@ -86,9 +86,10 @@ def record_hash(record, fieldset, params = {})
       end
 
       def id_from_record(record)
-         return record.send(record_id) if record_id
-         raise MandatoryField, 'id is a mandatory field in the jsonapi spec' unless record.respond_to?(:id)
-         record.id
+        return record_id.call(record) if record_id.is_a?(Proc)
+        return record.send(record_id) if record_id
+        raise MandatoryField, 'id is a mandatory field in the jsonapi spec' unless record.respond_to?(:id)
+        record.id
       end
 
       # Override #to_json for alternative implementation

lib/fast_jsonapi/version.rb

@@ -1,3 +1,3 @@
 module FastJsonapi
-  VERSION = "1.4"
+  VERSION = "1.5"
 end

spec/lib/extensions/active_record_spec.rb

@@ -71,3 +71,85 @@ class Account < ActiveRecord::Base
     File.delete(@db_file) if File.exist?(@db_file)
   end
 end
+
+describe 'active record has_one through' do
+  # Setup DB
+  before(:all) do
+    @db_file = "test_two.db"
+
+    # Open a database
+    db = SQLite3::Database.new @db_file
+
+    # Create tables
+    db.execute_batch <<-SQL
+      create table forests (
+        id int primary key,
+        name varchar(30)
+      );
+
+      create table trees (
+        id int primary key,
+        forest_id int,
+        name varchar(30),
+
+        FOREIGN KEY (forest_id) REFERENCES forests(id)
+      );
+
+      create table fruits (
+        id int primary key,
+        tree_id int,
+        name varchar(30),
+
+        FOREIGN KEY (tree_id) REFERENCES trees(id)
+      );
+    SQL
+
+    # Insert records
+    db.execute_batch <<-SQL
+      insert into forests values (1, 'sherwood');
+      insert into trees values (2, 1,'pine');
+      insert into fruits values (3, 2, 'pine nut');
+
+      insert into fruits(id,name) values (4,'apple');
+    SQL
+  end
+
+  # Setup Active Record
+  before(:all) do
+    class Forest < ActiveRecord::Base
+      has_many :trees
+    end
+
+    class Tree < ActiveRecord::Base
+      belongs_to :forest
+    end
+
+    class Fruit < ActiveRecord::Base
+      belongs_to :tree
+      has_one :forest, through: :tree
+    end
+
+    ActiveRecord::Base.establish_connection(
+      :adapter => 'sqlite3',
+      :database  => @db_file
+    )
+  end
+
+  context 'revenue' do
+    it 'has an forest_id' do
+      expect(Fruit.find(3).respond_to?(:forest_id)).to be true
+      expect(Fruit.find(3).forest_id).to eq 1
+      expect(Fruit.find(3).forest.name).to eq "sherwood"
+    end
+
+    it 'has nil if tree id not available' do
+      expect(Fruit.find(4).respond_to?(:tree_id)).to be true
+      expect(Fruit.find(4).forest_id).to eq nil
+    end
+  end
+
+  # Clean up DB
+  after(:all) do
+    File.delete(@db_file) if File.exist?(@db_file)
+  end
+end

spec/lib/object_serializer_attribute_param_spec.rb

@@ -15,7 +15,7 @@ def viewed?(user)
 
       class MovieSerializer
         attribute :viewed do |movie, params|
-          params ? movie.viewed?(params[:user]) : false
+          params[:user] ? movie.viewed?(params[:user]) : false
         end
 
         attribute :no_param_attribute do |movie|