Add blueprint extension hook and move deprecated 'view' option to it

Signed-off-by: Jordan Hollinger <[email protected]>

Author: jhollinger

lib/blueprinter/extension.rb

@@ -7,6 +7,7 @@ module Blueprinter
   # V2 hook call order:
   #
   # - around_hook (called around any other extension hook)
+  # - blueprint
   # - blueprint_fields
   # - blueprint_setup
   # - around_serialize_object | around_serialize_collection
@@ -27,6 +28,7 @@ module Blueprinter
   class Extension
     HOOKS = %i[
       around_hook
+      blueprint
       blueprint_fields
       blueprint_setup
       around_serialize_object
@@ -67,6 +69,9 @@ def hidden? = false
     # `blueprint_output` hooks. MUST yield!
     # @param context [Blueprinter::V2::Context::Object]
 
+    # blueprint: Returns the blueprint class to render with. The context's "fields" field will be empty.
+    # @param context [Blueprinter::V2::Context::Render]
+
     # blueprint_fields: Returns the fields that should be included in the correct order. Default is all fields in the order
     # in which they were defined.
     # NOTE If there are multiple blueprint_fields hooks, only the last one is called.

lib/blueprinter/extensions.rb

@@ -6,5 +6,6 @@ module Extensions
     autoload :FieldOrder, 'blueprinter/extensions/field_order'
     autoload :MultiJson, 'blueprinter/extensions/multi_json'
     autoload :OpenTelemetry, 'blueprinter/extensions/open_telemetry'
+    autoload :ViewOption, 'blueprinter/extensions/view_option'
   end
 end

lib/blueprinter/extensions/view_option.rb

@@ -0,0 +1,21 @@
+# frozen_string_literal: true
+
+module Blueprinter
+  module Extensions
+    #
+    # An optional, built-in extension for a ":view" option on render.
+    #
+    class ViewOption < Extension
+      # @param ctx [Blueprinter::V2::Context::Render]
+      def blueprint(ctx)
+        if (view = ctx.options[:view])
+          ctx.blueprint.class[view]
+        else
+          ctx.blueprint.class
+        end
+      end
+
+      def hidden? = true
+    end
+  end
+end

lib/blueprinter/v2/base.rb

@@ -1,5 +1,6 @@
 # frozen_string_literal: true
 
+require 'blueprinter/v2/instance_cache'
 require 'blueprinter/v2/render'
 
 module Blueprinter
@@ -87,21 +88,26 @@ def self.render(obj, options = {})
       end
 
       def self.render_object(obj, options = {})
-        # DEPRECATED
-        if options[:view]
-          options = options.dup
-          return self[options.delete(:view)].render_object(obj, options)
-        end
-        Render.new(obj, options, blueprint: self, collection: false)
+        instances = InstanceCache.new
+        blueprint = get_blueprint_class(instances, options)
+        Render.new(obj, options, blueprint:, instances:, collection: false)
       end
 
       def self.render_collection(objs, options = {})
-        # DEPRECATED
-        if options[:view]
-          options = options.dup
-          return self[options.delete(:view)].render_collection(objs, options)
+        instances = InstanceCache.new
+        blueprint = get_blueprint_class(instances, options)
+        Render.new(objs, options, blueprint:, instances:, collection: true)
+      end
+
+      # @api private
+      def self.get_blueprint_class(instances, options)
+        hooks = Hooks.new(extensions.map { |ext| instances.extension ext })
+        if hooks.registered? :blueprint
+          ctx = Context::Render.new(instances.blueprint(self), [], options, 1)
+          hooks.last(:blueprint, ctx) || self
+        else
+          self
         end
-        Render.new(objs, options, blueprint: self, collection: true)
       end
 
       # Apply partials and field exclusions

lib/blueprinter/v2/render.rb

@@ -1,31 +1,29 @@
 # frozen_string_literal: true
 
 require 'blueprinter/v2/serializer'
-require 'blueprinter/v2/instance_cache'
 
 module Blueprinter
   module V2
     class Render
-      def initialize(object, options, blueprint:, collection:)
+      def initialize(object, options, blueprint:, collection:, instances:)
         @object = object
         @options = options.dup.freeze
         @blueprint = blueprint
+        @instances = instances
         @collection = collection
       end
 
       # Serialize the object to a Hash or array of Hashes
       # @return [Hash|Array<Hash>]
       def to_hash
-        instances = InstanceCache.new
-        serializer = instances.serializer(@blueprint, @options, 1)
+        serializer = @instances.serializer(@blueprint, @options, 1)
         serialize serializer
       end
 
       # Serialize the object to a JSON string
       # @return [String]
       def to_json(_arg = nil)
-        instances = InstanceCache.new
-        serializer = instances.serializer(@blueprint, @options, 1)
+        serializer = @instances.serializer(@blueprint, @options, 1)
         result = serialize serializer
         ctx = Context::Result.new(serializer.blueprint, serializer.fields, @options, @object, result, 1)
         serializer.hooks.last(:json, ctx)

spec/extensions/view_option_spec.rb

@@ -0,0 +1,30 @@
+# frozen_string_literal: true
+
+describe Blueprinter::Extensions::ViewOption do
+  let(:instances) { Blueprinter::V2::InstanceCache.new }
+  let(:serializer) { Blueprinter::V2::Serializer.new(blueprint, {}, instances, initial_depth: 1) }
+  let(:context) { Blueprinter::V2::Context::Render }
+  let(:object) { { id: 42, foo: 'Foo', bar: 'Bar' } }
+  let(:blueprint) do
+    Class.new(Blueprinter::V2::Base) do
+      view :foo do
+        field :foo
+        view :bar do
+          field :bar
+        end
+      end
+    end
+  end
+
+  it 'does nothing by default' do
+    ctx = context.new(serializer.blueprint, [], {}, 1)
+    klass = described_class.new.blueprint ctx
+    expect(klass).to be blueprint
+  end
+
+  it 'finds a nested view' do
+    ctx = context.new(serializer.blueprint, [], { view: 'foo.bar' }, 1)
+    klass = described_class.new.blueprint ctx
+    expect(klass).to be blueprint['foo.bar']
+  end
+end

spec/v2/render_spec.rb

@@ -16,9 +16,11 @@
     end
   end
 
+  let(:instances) { Blueprinter::V2::InstanceCache.new }
+
   it 'renders an object to a hash' do
     widget = { name: 'Foo', description: 'About', category: { n: 'Bar' } }
-    render = described_class.new(widget, {}, blueprint: widget_blueprint, collection: false)
+    render = described_class.new(widget, {}, blueprint: widget_blueprint, collection: false, instances:)
 
     expect(render.to_hash).to eq({
       name: 'Foo',
@@ -32,7 +34,7 @@
       { name: 'Foo', description: 'About', category: { n: 'Bar' } },
       { name: 'Foo 2', description: 'About 2', category: { n: 'Bar 2' } },
     ]
-    render = described_class.new(widgets, {}, blueprint: widget_blueprint, collection: true)
+    render = described_class.new(widgets, {}, blueprint: widget_blueprint, collection: true, instances:)
 
     expect(render.to_hash).to eq([
       {
@@ -50,7 +52,7 @@
 
   it 'renders an object to JSON' do
     widget = { name: 'Foo', description: 'About', category: { n: 'Bar' } }
-    render = described_class.new(widget, {}, blueprint: widget_blueprint, collection: false)
+    render = described_class.new(widget, {}, blueprint: widget_blueprint, collection: false, instances:)
 
     expect(render.to_json).to eq({
       name: 'Foo',
@@ -61,7 +63,7 @@
 
   it 'renders a collection to JSON' do
     widget = { name: 'Foo', description: 'About', category: { n: 'Bar' } }
-    render = described_class.new([widget], {}, blueprint: widget_blueprint, collection: true)
+    render = described_class.new([widget], {}, blueprint: widget_blueprint, collection: true, instances:)
 
     expect(render.to_json).to eq([{
       name: 'Foo',
@@ -86,15 +88,15 @@ def json(ctx)
     widget_blueprint.extensions << json_ext.new('A', log)
     widget_blueprint.extensions << json_ext.new('B', log)
 
-    render = described_class.new({ name: 'Foo' }, {}, blueprint: widget_blueprint, collection: false)
+    render = described_class.new({ name: 'Foo' }, {}, blueprint: widget_blueprint, collection: false, instances:)
 
     expect(render.to_json).to eq '{"name":"Foo"}'
     expect(log).to eq ['B: custom json!']
   end
 
   it 'renders to JSON and ignores the arg (for Rails `render json:`)' do
     widget = { name: 'Foo', description: 'About', category: { n: 'Bar' } }
-    render = described_class.new([widget], {}, blueprint: widget_blueprint, collection: true)
+    render = described_class.new([widget], {}, blueprint: widget_blueprint, collection: true, instances:)
 
     expect(render.to_json({ junk: 'junk' })).to eq([{
       name: 'Foo',
@@ -105,7 +107,7 @@ def json(ctx)
 
   it 'responds to to_str with json' do
     widget = { name: 'Foo', description: 'About', category: { n: 'Bar' } }
-    render = described_class.new(widget, {}, blueprint: widget_blueprint, collection: false)
+    render = described_class.new(widget, {}, blueprint: widget_blueprint, collection: false, instances:)
 
     expect(render.to_str).to eq({
       name: 'Foo',
@@ -122,7 +124,7 @@ def json(ctx)
     end
     widget_blueprint.extensions << ext.new
     widget = { name: 'Foo', description: 'About', category: { n: 'Bar' } }
-    render = described_class.new(widget, {}, blueprint: widget_blueprint, collection: false)
+    render = described_class.new(widget, {}, blueprint: widget_blueprint, collection: false, instances:)
 
     expect(render.to_json).to eq({
       name: 'Foo',

spec/v2/rendering_spec.rb

@@ -90,7 +90,8 @@
     })
   end
 
-  it 'renders an object with the deprecated view option' do
+  it 'renders an object using the blueprint hook' do
+    widget_blueprint.extensions << Blueprinter::Extensions::ViewOption.new
     result = widget_blueprint.render_object(widget, { view: :extended }).to_hash
     expect(result).to eq({
       name: 'Foo',
@@ -100,7 +101,8 @@
     })
   end
 
-  it 'renders a collection with the deprecated view option' do
+  it 'renders a collection using the blueprint hook' do
+    widget_blueprint.extensions << Blueprinter::Extensions::ViewOption.new
     result = widget_blueprint.render_collection([widget], { view: :extended }).to_hash
     expect(result).to eq([{
       name: 'Foo',