v3(services): introduce service route binding endpoint (cloudfoundry#1789)

[#174063444](https://www.pivotaltracker.com/story/show/174063444)

Author: blgm

app/controllers/v3/service_route_bindings_controller.rb

@@ -0,0 +1,63 @@
+require 'messages/service_route_binding_create_message'
+
+class ServiceRouteBindingsController < ApplicationController
+  def create
+    message = parse_request
+
+    service_instance = fetch_service_instance(message.service_instance_guid)
+    route = fetch_route(message.route_guid)
+    check_space(service_instance, route)
+
+    head :not_implemented
+  end
+
+  private
+
+  def parse_request
+    message = ServiceRouteBindingCreateMessage.new(hashed_params[:body])
+    unprocessable!(message.errors.full_messages) unless message.valid?
+    message
+  end
+
+  def fetch_service_instance(guid)
+    service_instance = VCAP::CloudController::ServiceInstance.first(guid: guid)
+    unless service_instance && can_read_space?(service_instance.space)
+      unprocessable_service_instance!(guid)
+    end
+    service_instance
+  end
+
+  def fetch_route(guid)
+    route = VCAP::CloudController::Route.first(guid: guid)
+    unless route && can_read_space?(route.space)
+      unprocessable_route!(guid)
+    end
+    route
+  end
+
+  def check_space(service_instance, route)
+    space = service_instance.space
+    space_mismatch! unless space == route.space
+    unauthorized! unless can_write_space?(space)
+  end
+
+  def can_read_space?(space)
+    permission_queryer.can_read_from_space?(space.guid, space.organization_guid)
+  end
+
+  def can_write_space?(space)
+    permission_queryer.can_write_to_space?(space.guid)
+  end
+
+  def unprocessable_service_instance!(guid)
+    unprocessable!("The service instance could not be found: #{guid}")
+  end
+
+  def unprocessable_route!(guid)
+    unprocessable!("The route could not be found: #{guid}")
+  end
+
+  def space_mismatch!
+    unprocessable!('The service instance and the route are in different spaces.')
+  end
+end

app/messages/service_route_binding_create_message.rb

@@ -0,0 +1,33 @@
+require 'messages/base_message'
+require 'utils/hash_utils'
+
+module VCAP::CloudController
+  class ServiceRouteBindingCreateMessage < BaseMessage
+    register_allowed_keys [:relationships]
+
+    validates_with NoAdditionalKeysValidator, RelationshipValidator
+
+    delegate :route_guid, :service_instance_guid, to: :relationships_message
+
+    def relationships_message
+      @relationships_message ||= Relationships.new(relationships.deep_symbolize_keys)
+    end
+
+    class Relationships < BaseMessage
+      register_allowed_keys [:service_instance, :route]
+
+      def route_guid
+        HashUtils.dig(route, :data, :guid)
+      end
+
+      def service_instance_guid
+        HashUtils.dig(service_instance, :data, :guid)
+      end
+
+      validates_with NoAdditionalKeysValidator
+
+      validates :service_instance, presence: true, allow_nil: false, to_one_relationship: true
+      validates :route, presence: true, allow_nil: false, to_one_relationship: true
+    end
+  end
+end

config/routes.rb

@@ -189,6 +189,11 @@
             param: :guid,
             only: [:show, :index]
 
+  # service_route_bindings
+  resources :service_route_bindings,
+    param: :guid,
+    only: [:create]
+
   # service_brokers
   get '/service_brokers', to: 'service_brokers#index'
   get '/service_brokers/:guid', to: 'service_brokers#show'

spec/request/service_route_bindings_spec.rb

@@ -0,0 +1,124 @@
+require 'spec_helper'
+require 'request_spec_shared_examples'
+
+RSpec.describe 'v3 service route bindings' do
+  describe 'POST /v3/service_route_bindings' do
+    let(:api_call) { ->(user_headers) { post '/v3/service_route_bindings', request.to_json, user_headers } }
+
+    let(:service_instance) { VCAP::CloudController::UserProvidedServiceInstance.make(space: space) }
+    let(:route) { VCAP::CloudController::Route.make(space: space) }
+    let(:request) do
+      {
+        relationships: {
+          service_instance: {
+            data: {
+              guid: service_instance.guid
+            }
+          },
+          route: {
+            data: {
+              guid: route.guid
+            }
+          }
+        }
+      }
+    end
+
+    describe 'permissions' do
+      it_behaves_like 'permissions for single object endpoint', ALL_PERMISSIONS do
+        let(:expected_codes_and_responses) do
+          Hash.new(code: 403).tap do |h|
+            h['admin'] = { code: 501 }
+            h['space_developer'] = { code: 501 }
+
+            h['no_role'] = { code: 422 }
+            h['org_auditor'] = { code: 422 }
+            h['org_billing_manager'] = { code: 422 }
+          end
+        end
+      end
+    end
+
+    describe 'errors' do
+      context 'invalid body' do
+        let(:request) do
+          { foo: 'bar' }
+        end
+
+        it 'fails with a 422 unprocessable' do
+          api_call.call(space_dev_headers)
+
+          expect(last_response).to have_status_code(422)
+          expect(parsed_response['errors']).to include(
+            include({
+              'detail' => "Unknown field(s): 'foo', Relationships 'relationships' is not an object",
+              'title' => 'CF-UnprocessableEntity',
+              'code' => 10008,
+            })
+          )
+        end
+      end
+
+      context 'cannot read service instance' do
+        let(:service_instance) { VCAP::CloudController::UserProvidedServiceInstance.make }
+
+        it 'fails with a 422 unprocessable' do
+          api_call.call(space_dev_headers)
+
+          expect(last_response).to have_status_code(422)
+          expect(parsed_response['errors']).to include(
+            include({
+              'detail' => "The service instance could not be found: #{service_instance.guid}",
+              'title' => 'CF-UnprocessableEntity',
+              'code' => 10008,
+            })
+          )
+        end
+      end
+
+      context 'cannot read route' do
+        let(:route) { VCAP::CloudController::Route.make }
+
+        it 'fails with a 422 unprocessable' do
+          api_call.call(space_dev_headers)
+
+          expect(last_response).to have_status_code(422)
+          expect(parsed_response['errors']).to include(
+            include({
+              'detail' => "The route could not be found: #{route.guid}",
+              'title' => 'CF-UnprocessableEntity',
+              'code' => 10008,
+            })
+          )
+        end
+      end
+
+      context 'route and service instance in different spaces' do
+        let(:route) { VCAP::CloudController::Route.make }
+
+        it 'fails with a 422 unprocessable' do
+          api_call.call(admin_headers)
+
+          expect(last_response).to have_status_code(422)
+          expect(parsed_response['errors']).to include(
+            include({
+              'detail' => 'The service instance and the route are in different spaces.',
+              'title' => 'CF-UnprocessableEntity',
+              'code' => 10008,
+            })
+          )
+        end
+      end
+    end
+  end
+
+  let(:user) { VCAP::CloudController::User.make }
+  let(:org) { VCAP::CloudController::Organization.make }
+  let(:space) { VCAP::CloudController::Space.make(organization: org) }
+
+  let(:space_dev_headers) do
+    org.add_user(user)
+    space.add_developer(user)
+    headers_for(user)
+  end
+end

spec/unit/messages/service_route_binding_create_message_spec.rb

@@ -0,0 +1,64 @@
+require 'lightweight_spec_helper'
+require 'messages/service_route_binding_create_message'
+
+module VCAP::CloudController
+  RSpec.describe ServiceRouteBindingCreateMessage do
+    let(:body) do
+      {
+        relationships: {
+          service_instance: {
+            data: { guid: 'service-instance-guid' }
+          },
+          route: {
+            data: { guid: 'route-guid' }
+          }
+        }
+      }
+    end
+
+    let(:message) { described_class.new(body) }
+
+    it 'accepts the allowed keys' do
+      expect(message).to be_valid
+      expect(message.requested?(:relationships)).to be_truthy
+    end
+
+    it 'builds the right message' do
+      expect(message.service_instance_guid).to eq('service-instance-guid')
+      expect(message.route_guid).to eq('route-guid')
+    end
+
+    describe 'validations' do
+      it 'is invalid when there are unknown keys' do
+        body[:parameters] = 'foo'
+        expect(message).to_not be_valid
+        expect(message.errors.full_messages).to include("Unknown field(s): 'parameters'")
+      end
+
+      describe 'service instance relationship' do
+        it 'fails when not present' do
+          body[:relationships][:service_instance] = nil
+          message.valid?
+          expect(message).to_not be_valid
+          expect(message.errors[:relationships]).to include(
+            "Service instance can't be blank",
+            /Service instance must be structured like this.*/
+          )
+          expect(message.errors[:relationships].count).to eq(2)
+        end
+      end
+
+      describe 'route relationship' do
+        it 'fails when not present' do
+          body[:relationships][:route] = nil
+          expect(message).to_not be_valid
+          expect(message.errors[:relationships]).to include(
+            "Route can't be blank",
+            /Route must be structured like this.*/,
+          )
+          expect(message.errors[:relationships].count).to eq(2)
+        end
+      end
+    end
+  end
+end