Adding approval process

pkg/registrar/internal/services/app_registration.go

@@ -0,0 +1,2 @@
+package services
+

pkg/registrar/internal/services/approvals.go

@@ -0,0 +1,5 @@
+package services
+
+type ApprovalRequester interface {
+	SendApprovalRequest(appName string) error
+}

pkg/registrar/internal/services/pubsub.go

@@ -0,0 +1,14 @@
+package services
+
+type Publisher interface {
+	Publish(topic string, message string)
+}
+
+type PubSub interface {
+	Publisher
+	Subscriber
+}
+
+type Subscriber interface {
+	Subscribe(topic string) <-chan string
+}

pkg/registrar/internal/services/repo.go

@@ -0,0 +1,26 @@
+package services
+
+import (
+	"errors"
+	"fmt"
+
+	"github.com/google/uuid"
+)
+
+var (
+	ErrAppRepo             = errors.New("AppRepo")
+	ErrApplicationNotFound = fmt.Errorf("%w: application not found", ErrAppRepo)
+)
+
+type Application struct {
+	ID    uuid.UUID
+	Name  string
+	State string
+}
+
+type AppRepo interface {
+	IsRegistered(name string) bool
+	PendingApprovalCount() int
+	StartAppRegistration(name string) uuid.UUID
+	ApproveApp(id uuid.UUID) (Application, error)
+}