Get name of service broker in service offering request

[#172379562](https://www.pivotaltracker.com/story/show/172379562)

Author: pivotal-marcela-campo

app/controllers/v3/service_offerings_controller.rb

@@ -3,6 +3,7 @@
 require 'fetchers/service_plan_visibility_fetcher'
 require 'presenters/v3/service_offering_presenter'
 require 'messages/service_offerings_list_message'
+require 'messages/service_offerings_show_message'
 require 'messages/metadata_update_message'
 require 'messages/purge_message'
 require 'actions/service_offering_delete'
@@ -52,7 +53,13 @@ def show
     service_offering_not_found! if service_offering.nil?
     service_offering_not_found! unless visible_to_current_user?(service: service_offering)
 
-    presenter = Presenters::V3::ServiceOfferingPresenter.new(service_offering)
+    message = ServiceOfferingsShowMessage.from_params(query_params)
+    invalid_param!(message.errors.full_messages) unless message.valid?
+
+    decorators = []
+    decorators << FieldServiceOfferingServiceBrokerDecorator.new(message.fields) if FieldServiceOfferingServiceBrokerDecorator.match?(message.fields)
+
+    presenter = Presenters::V3::ServiceOfferingPresenter.new(service_offering, decorators: decorators)
     render status: :ok, json: presenter.to_json
   end
 

app/messages/service_offerings_show_message.rb

@@ -0,0 +1,16 @@
+module VCAP::CloudController
+  class ServiceOfferingsShowMessage < BaseMessage
+    register_allowed_keys [:fields]
+
+    validates_with NoAdditionalParamsValidator
+    validates :fields, allow_nil: true, fields: {
+      allowed: {
+        'service_broker' => ['guid', 'name']
+      }
+    }
+
+    def self.from_params(params)
+      super(params, [], fields: %w(fields))
+    end
+  end
+end

app/presenters/v3/service_offering_presenter.rb

@@ -12,7 +12,7 @@ class ServiceOfferingPresenter < BasePresenter
         def to_hash
           metadata = broker_metadata
 
-          {
+          hash = {
             guid: service_offering.guid,
             name: service_offering.label,
             description: service_offering.description,
@@ -41,6 +41,10 @@ def to_hash
             },
             links: build_links,
           }
+
+          @decorators.reduce(hash) { |memo, d| d.decorate(memo, [service_offering]) }
+
+          hash
         end
 
         private

docs/v3/source/includes/experimental_resources/service_offerings/_get.md.erb

@@ -26,6 +26,19 @@ This endpoint retrieves the service offering by GUID.
 #### Definition
 `GET /v3/service_offerings/:guid`
 
+#### Query parameters
+
+Name | Type | Description
+---- | ---- | ------------
+**fields** | [_fields parameter_](#fields-parameter) | [_Allowed values_](#service-offering-fields)
+
+##### Service Offering Fields
+
+Resource            | Allowed Keys
+------------------- | ----
+service_broker| `guid`, `name`
+
+
 #### Permitted roles
  |
 --- | ---

spec/field_message_spec_shared_examples.rb

@@ -40,3 +40,19 @@
     ))
   end
 end
+
+RSpec.shared_examples 'fields query hash' do
+  it 'validates `fields` is a hash' do
+    message = described_class.from_params({ 'fields' => 'foo' }.with_indifferent_access)
+    expect(message).not_to be_valid
+    expect(message.errors[:fields][0]).to include('must be an object')
+  end
+
+  it 'does not accept fields resources that are not allowed' do
+    message = described_class.from_params({ 'fields' => { 'space.foo': 'name' } })
+    expect(message).not_to be_valid
+    expect(message.errors[:fields]).to include(include(
+                                                 '[space.foo] valid resources are:'
+    ))
+  end
+end

spec/request/service_offerings_spec.rb

@@ -183,6 +183,19 @@
         })
       end
     end
+
+    describe 'fields' do
+      let!(:service_offering) { VCAP::CloudController::Service.make }
+
+      it 'can include service broker name and guid' do
+        get "/v3/service_offerings/#{service_offering.guid}?fields[service_broker]=name,guid", nil, admin_headers
+        expect(last_response).to have_status_code(200)
+
+        expect(parsed_response['included']['service_brokers']).to have(1).elements
+        expect(parsed_response['included']['service_brokers'][0]['guid']).to eq(service_offering.service_broker.guid)
+        expect(parsed_response['included']['service_brokers'][0]['name']).to eq(service_offering.service_broker.name)
+      end
+    end
   end
 
   describe 'GET /v3/service_offerings' do

spec/unit/messages/service_instance_show_message_spec.rb

@@ -14,19 +14,6 @@ module VCAP::CloudController
 
     it_behaves_like 'field query parameter', 'service_plan.service_offering.service_broker', 'name,guid'
 
-    it 'does not accept fields resources that are not allowed' do
-      message = described_class.from_params({ 'fields' => { 'space.foo': 'name' } })
-      expect(message).not_to be_valid
-      expect(message.errors[:fields]).to include(
-        '[space.foo] valid resources are: ' \
-        "'space', 'space.organization', 'service_plan', 'service_plan.service_offering', 'service_plan.service_offering.service_broker'"
-      )
-    end
-
-    it 'does not accept other parameters' do
-      message = described_class.from_params({ 'foobar' => 'pants' })
-      expect(message).not_to be_valid
-      expect(message.errors[:base][0]).to include("Unknown query parameter(s): 'foobar'")
-    end
+    it_behaves_like 'fields query hash'
   end
 end

spec/unit/messages/service_instances_list_message_spec.rb

@@ -77,11 +77,7 @@ module VCAP::CloudController
       end
 
       context 'fields' do
-        it 'validates `fields` is a hash' do
-          message = described_class.from_params({ 'fields' => 'foo' }.with_indifferent_access)
-          expect(message).not_to be_valid
-          expect(message.errors[:fields][0]).to include('must be an object')
-        end
+        it_behaves_like 'fields query hash'
 
         it_behaves_like 'field query parameter', 'space', 'guid,name,relationships.organization'
 
@@ -92,14 +88,6 @@ module VCAP::CloudController
         it_behaves_like 'field query parameter', 'service_plan.service_offering', 'name,guid,relationships.service_broker'
 
         it_behaves_like 'field query parameter', 'service_plan.service_offering.service_broker', 'name,guid'
-
-        it 'does not accept fields resources that are not allowed' do
-          message = described_class.from_params({ 'fields' => { 'space.foo': 'name' } })
-          expect(message).not_to be_valid
-          expect(message.errors[:fields]).to include(
-            "[space.foo] valid resources are: 'space', 'space.organization', " \
-            "'service_plan', 'service_plan.service_offering', 'service_plan.service_offering.service_broker'")
-        end
       end
 
       context 'type' do

spec/unit/messages/service_offering_show_message_spec.rb

@@ -0,0 +1,46 @@
+require 'spec_helper'
+require 'messages/service_offerings_show_message'
+require 'field_message_spec_shared_examples'
+
+module VCAP::CloudController
+  RSpec.describe ServiceOfferingsShowMessage do
+    describe '.from_params' do
+      let(:params) do
+        {
+          'fields' => { 'service_broker' => 'guid,name' },
+        }.with_indifferent_access
+      end
+
+      it 'returns the correct message' do
+        message = described_class.from_params(params)
+
+        expect(message).to be_valid
+        expect(message).to be_a(described_class)
+        expect(message.fields).to match({ 'service_broker': ['guid', 'name'] })
+      end
+
+      it 'converts requested keys to symbols' do
+        message = described_class.from_params(params)
+        expect(message.requested?(:fields)).to be_truthy
+      end
+
+      it 'accepts an empty set' do
+        message = described_class.from_params({})
+        expect(message).to be_valid
+      end
+
+      it 'does not accept arbitrary parameters' do
+        message = described_class.from_params({ foobar: 'pants' }.with_indifferent_access)
+
+        expect(message).not_to be_valid
+        expect(message.errors[:base][0]).to include("Unknown query parameter(s): 'foobar'")
+      end
+
+      context 'fields' do
+        it_behaves_like 'fields query hash'
+
+        it_behaves_like 'field query parameter', 'service_broker', 'guid,name'
+      end
+    end
+  end
+end

spec/unit/messages/service_offerings_list_message_spec.rb

@@ -74,6 +74,8 @@ module VCAP::CloudController
       end
 
       context 'fields' do
+        it_behaves_like 'fields query hash'
+
         it_behaves_like 'field query parameter', 'service_broker', 'guid,name'
       end
     end