Throw an error on sb bind when route binding status is delete_failed …

…or delete_in_progess

This is a fix as part of #2637. It contains changes for:
POST /v3/service_route_bindings

Two behaviours change with this PR:
1: When a service route binding is in state delete_in_progess or delete_failed, we want an
error different from "Route is already bound to the service instance" to be thrown. It will now throw an error with "The binding is getting deleted or its deletion failed".
2: When a service route binding is in state create_failed, it should recreate the binding and not reject the request with "Route is already bound to the service instance".

With regard to point 1: it's important to note that the initial statement may not be entirely accurate,
as there's a possibility that orphan mitigation processes may have already removed the binding in question.
The Cloud Foundry Command Line Interface (CF CLI) correctly interprets the situation as a success.
This is because the message conveyed to the CF CLI indicates that the task it was instructed to perform
as already been completed. As a result, if the CF CLI is attempting to create a service route binding but
finds that a binding already exists in a state where it's either failed deletion or is pending deletion,
the CF CLI will consider this a failure.

app/actions/service_route_binding_create.rb

@@ -15,7 +15,9 @@ def initialize(user_audit_info, audit_hash)
       PERMITTED_BINDING_ATTRIBUTES = [:route_service_url].freeze
 
       def precursor(service_instance, route, message:)
-        validate!(service_instance, route)
+        validate_service_instance!(service_instance, route)
+        binding = RouteBinding.first(service_instance:, route:)
+        validate_binding!(binding)
 
         binding_details = {
           service_instance:,
@@ -24,6 +26,7 @@ def precursor(service_instance, route, message:)
 
         RouteBinding.new.tap do |b|
           RouteBinding.db.transaction do
+            binding.destroy if binding
             b.save_with_attributes_and_new_operation(
               binding_details,
               CREATE_INITIAL_OPERATION
@@ -43,19 +46,25 @@ def event_repository
         )
       end
 
-      def validate!(service_instance, route)
+      def validate_service_instance!(service_instance, route)
         not_supported! unless service_instance.route_service?
         not_bindable! unless service_instance.bindable?
         route_is_internal! if route.try(:internal?)
         space_mismatch! unless route.space == service_instance.space
-        already_exists! if route.service_instance == service_instance
-        already_bound! if route.service_instance
+        already_bound! if route.service_instance && route.service_instance != service_instance
         return unless service_instance.managed_instance?
 
         service_instance_not_found! if service_instance.create_failed?
         operation_in_progress! if service_instance.operation_in_progress?
       end
 
+      def validate_binding!(binding)
+        return unless binding
+
+        already_exists! if binding.create_succeeded? || binding.create_in_progress?
+        incomplete_deletion! if binding.delete_failed? || binding.delete_in_progress?
+      end
+
       def permitted_binding_attributes
         PERMITTED_BINDING_ATTRIBUTES
       end
@@ -87,6 +96,10 @@ def not_bindable!
       def already_exists!
         raise RouteBindingAlreadyExists.new('The route and service instance are already bound')
       end
+
+      def incomplete_deletion!
+        raise UnprocessableCreate.new('The binding is getting deleted or its deletion failed')
+      end
     end
   end
 end

spec/unit/actions/service_route_binding_create_spec.rb

@@ -79,15 +79,83 @@ module V3
           end
 
           context 'route binding already exists' do
-            it 'raises an error' do
-              RouteBinding.make(service_instance:, route:)
+            let!(:binding) { RouteBinding.make(service_instance:, route:) }
+
+            context 'when no last service route binding operation exists' do
+              it 'raises an error' do
+                expect do
+                  action.precursor(service_instance, route, message:)
+                end.to raise_error(
+                         ServiceRouteBindingCreate::RouteBindingAlreadyExists,
+                         'The route and service instance are already bound'
+                       )
+              end
+            end
 
-              expect do
-                action.precursor(service_instance, route, message:)
-              end.to raise_error(
-                ServiceRouteBindingCreate::RouteBindingAlreadyExists,
-                'The route and service instance are already bound'
-              )
+            context "when the last service route binding operation is in 'create succeeded' state" do
+              before do
+                binding.save_with_attributes_and_new_operation({}, { type: 'create', state: 'succeeded' })
+              end
+
+              it 'raises an error' do
+                expect { action.precursor(service_instance, route, message:) }.to raise_error(
+                  ServiceRouteBindingCreate::RouteBindingAlreadyExists,
+                  'The route and service instance are already bound'
+                )
+              end
+            end
+
+            context "when the last service route binding operation is in 'create in progress' state" do
+              before do
+                binding.save_with_attributes_and_new_operation({}, { type: 'create', state: 'in progress' })
+              end
+
+              it 'raises an error' do
+                expect { action.precursor(service_instance, route, message:) }.to raise_error(
+                  ServiceRouteBindingCreate::RouteBindingAlreadyExists,
+                  'The route and service instance are already bound'
+                )
+              end
+            end
+
+            context "when the last service route binding operation is in 'create failed' state" do
+              before do
+                binding.save_with_attributes_and_new_operation({}, { type: 'create', state: 'failed' })
+              end
+
+              it 'deletes the existing binding and creates a new one' do
+                b = action.precursor(service_instance, route, message:)
+
+                expect(b.guid).not_to eq(binding.guid)
+                expect(b).to be_create_in_progress
+                expect { binding.reload }.to raise_error Sequel::NoExistingObject
+              end
+            end
+
+            context "when the last service route binding operation is in 'delete in progress' state" do
+              before do
+                binding.save_with_attributes_and_new_operation({}, { type: 'delete', state: 'in progress' })
+              end
+
+              it 'raises an error' do
+                expect { action.precursor(service_instance, route, message:) }.to raise_error(
+                  ServiceRouteBindingCreate::UnprocessableCreate,
+                  'The binding is getting deleted or its deletion failed'
+                )
+              end
+            end
+
+            context "when the last service route binding operation is in 'delete failed' state" do
+              before do
+                binding.save_with_attributes_and_new_operation({}, { type: 'delete', state: 'failed' })
+              end
+
+              it 'raises an error' do
+                expect { action.precursor(service_instance, route, message:) }.to raise_error(
+                  ServiceRouteBindingCreate::UnprocessableCreate,
+                  'The binding is getting deleted or its deletion failed'
+                )
+              end
             end
           end