v3(services): Allow users to get a list of route bindings

[#174192797](https://www.pivotaltracker.com/story/show/174192797)

Signed-off-by: Brian Butz <bbutz@pivotal.io>

Author: Urse Searle

app/controllers/v3/service_route_bindings_controller.rb

@@ -2,6 +2,7 @@
 require 'actions/service_route_binding_create'
 require 'jobs/v3/create_route_binding_job'
 require 'presenters/v3/service_route_binding_presenter'
+require 'fetchers/route_binding_list_fetcher'
 
 class ServiceRouteBindingsController < ApplicationController
   def create
@@ -40,8 +41,32 @@ def show
     render status: :ok, json: Presenters::V3::ServiceRouteBindingPresenter.new(route_binding)
   end
 
+  def index
+    route_bindings = fetch_route_bindings
+    message = ListMessage.from_params(query_params, [])
+    render status: :ok, json: Presenters::V3::PaginatedListPresenter.new(
+      presenter: Presenters::V3::ServiceRouteBindingPresenter,
+      paginated_result: SequelPaginator.new.get_page(route_bindings, message.try(:pagination_options)),
+      path: '/v3/service_route_bindings',
+      message: message,
+    )
+  end
+
   private
 
+  def fetch_route_bindings
+    fetcher = RouteBindingListFetcher.new
+    if permission_queryer.can_read_globally?
+      fetcher.fetch_all
+    else
+      fetcher.fetch_some(space_guids: space_guids)
+    end
+  end
+
+  def space_guids
+    permission_queryer.readable_space_guids
+  end
+
   def parse_create_request
     message = ServiceRouteBindingCreateMessage.new(hashed_params[:body])
     unprocessable!(message.errors.full_messages) unless message.valid?

app/fetchers/route_binding_list_fetcher.rb

@@ -0,0 +1,17 @@
+module VCAP
+  module CloudController
+    class RouteBindingListFetcher
+      def fetch_all
+        RouteBinding.dataset
+      end
+
+      def fetch_some(space_guids:)
+        RouteBinding.dataset.
+          join(:service_instances, id: Sequel[:route_bindings][:service_instance_id]).
+          join(:spaces, id: Sequel[:service_instances][:space_id]).
+          where { Sequel[:spaces][:guid] =~ space_guids }.
+          select_all(:route_bindings)
+      end
+    end
+  end
+end

config/routes.rb

@@ -197,7 +197,7 @@
   # service_route_bindings
   resources :service_route_bindings,
     param: :guid,
-    only: [:show, :create]
+    only: [:show, :create, :index]
 
   # service_brokers
   get '/service_brokers', to: 'service_brokers#index'

spec/request/service_route_bindings_spec.rb

@@ -641,6 +641,67 @@
     end
   end
 
+  describe 'GET /v3/service_route_bindings' do
+    describe 'no bindings to list' do
+      let(:api_call) { ->(user_headers) { get '/v3/service_route_bindings', nil, user_headers } }
+      let(:expected_codes_and_responses) do
+        Hash.new(code: 200, response_objects: [])
+      end
+
+      it_behaves_like 'permissions for list endpoint', ALL_PERMISSIONS
+    end
+
+    describe 'a mix of bindings' do
+      let(:route) { VCAP::CloudController::Route.make(space: space) }
+      let(:service_instance_1) { VCAP::CloudController::UserProvidedServiceInstance.make(:routing, space: space, route_service_url: route_service_url) }
+      let(:service_instance_2) { VCAP::CloudController::ManagedServiceInstance.make(:routing, space: space, route_service_url: route_service_url) }
+      let(:route_binding_1) do
+        bind_service_to_route(service_instance_1, route)
+      end
+      let(:route_binding_2) do
+        bind_service_to_route(service_instance_2, route)
+      end
+      let(:api_call) { ->(user_headers) { get '/v3/service_route_bindings', nil, user_headers } }
+      let(:response_objects) do
+        [
+          expected_json(
+            binding_guid: route_binding_1.guid,
+              route_service_url: route_service_url,
+              service_instance_guid: service_instance_1.guid,
+              route_guid: route.guid,
+              last_operation_type: 'create',
+              last_operation_state: 'successful',
+          ),
+          expected_json(
+            binding_guid: route_binding_2.guid,
+            route_service_url: route_service_url,
+            service_instance_guid: service_instance_2.guid,
+            route_guid: route.guid,
+            last_operation_type: 'create',
+            last_operation_state: 'successful',
+          )
+        ]
+      end
+      let(:bindings_response_body) do
+        { code: 200, response_objects: response_objects }
+      end
+
+      let(:expected_codes_and_responses) do
+        Hash.new(code: 200, response_objects: []).tap do |h|
+          h['admin'] = bindings_response_body
+          h['admin_read_only'] = bindings_response_body
+          h['global_auditor'] = bindings_response_body
+          h['space_developer'] = bindings_response_body
+          h['space_manager'] = bindings_response_body
+          h['space_auditor'] = bindings_response_body
+          h['org_manager'] = bindings_response_body
+        end
+      end
+
+      it_behaves_like 'permissions for list endpoint', ALL_PERMISSIONS
+    end
+  end
+
   describe 'GET /v3/service_route_bindings/:guid' do
     let(:api_call) { ->(user_headers) { get "/v3/service_route_bindings/#{guid}", nil, user_headers } }
     let(:route) { VCAP::CloudController::Route.make(space: space) }
@@ -755,4 +816,12 @@ def expected_json(binding_guid:, route_service_url:, route_guid:, service_instan
       }
     }
   end
+
+  def bind_service_to_route(service_instance, route)
+    route_service_url = service_instance.route_service_url
+    VCAP::CloudController::RouteBinding.new.save_with_new_operation(
+      { service_instance: service_instance, route: route, route_service_url: route_service_url },
+        { type: 'create', state: 'successful' }
+    )
+  end
 end

spec/unit/fetchers/route_binding_list_fetcher_spec.rb

@@ -0,0 +1,40 @@
+require 'spec_helper'
+
+module VCAP
+  module CloudController
+    RSpec.describe RouteBindingListFetcher do
+      let(:fetcher) { RouteBindingListFetcher.new }
+
+      describe 'fetch_all' do
+        it 'should return all route bindings' do
+          route_bindings = Array.new(3) { RouteBinding.make }
+
+          fetched_route_bindings = fetcher.fetch_all
+
+          fetched_route_binding_guids = fetched_route_bindings.map(&:guid)
+          expected_route_binding_guids = route_bindings.map(&:guid)
+          expect(fetched_route_binding_guids).to eq(expected_route_binding_guids)
+        end
+      end
+
+      describe 'fetch_some' do
+        it 'it should return route bindings related to a set of space guids' do
+          target_space = Space.make
+          service_instance_in_target_space = UserProvidedServiceInstance.make(:routing, space: target_space)
+          make_other_route_bindings
+          route_bindings_in_target_space = Array.new(3) { RouteBinding.make(service_instance: service_instance_in_target_space) }
+
+          fetched_route_bindings = fetcher.fetch_some(space_guids: [target_space.guid])
+
+          fetched_route_binding_guids = fetched_route_bindings.map(&:guid)
+          target_space_route_binding_guids = route_bindings_in_target_space.map(&:guid)
+          expect(fetched_route_binding_guids).to eq(target_space_route_binding_guids)
+        end
+
+        def make_other_route_bindings
+          Array.new(3) { RouteBinding.make }
+        end
+      end
+    end
+  end
+end