4 files changed, 65 insertions, 36 deletions
diff --git a/pkg/db/entity.go b/pkg/db/entity.go
new file mode 100644
index 0000000..1dcf4c3
--- /dev/null
+++ b/pkg/db/entity.go
@@ -0,0 +1,7 @@
+package db
+
+type Entity interface {
+	GetID() string
+	SetID(id string) error
+	Validate() error
+}
diff --git a/pkg/db/in_memory_repository.go b/pkg/db/in_memory_repository.go
new file mode 100644
index 0000000..5859c0b
--- /dev/null
+++ b/pkg/db/in_memory_repository.go
@@ -0,0 +1,39 @@
+package db
+
+import (
+	"github.com/xlgmokha/x/pkg/x"
+	"gitlab.com/gitlab-org/software-supply-chain-security/authorization/sparkled/pkg/pls"
+)
+
+type inMemoryRepository[T Entity] struct {
+	items []T
+}
+
+func NewRepository[T Entity]() Repository[T] {
+	return &inMemoryRepository[T]{
+		items: []T{},
+	}
+}
+
+func (r *inMemoryRepository[T]) All() []T {
+	return r.items
+}
+
+func (r *inMemoryRepository[T]) Find(id string) T {
+	return x.Find(r.All(), func(item T) bool {
+		return item.GetID() == id
+	})
+}
+
+func (r *inMemoryRepository[T]) Save(item T) error {
+	if err := item.Validate(); err != nil {
+		return err
+	}
+
+	if item.GetID() == "" {
+		item.SetID(pls.GenerateULID())
+	}
+
+	r.items = append(r.items, item)
+	return nil
+}
diff --git a/pkg/db/repository_test.go b/pkg/db/in_memory_repository_test.go
index bb788d2..382a656 100644
--- a/pkg/db/repository_test.go
+++ b/pkg/db/in_memory_repository_test.go
@@ -8,7 +8,7 @@ import (
 	"gitlab.com/gitlab-org/software-supply-chain-security/authorization/sparkled/pkg/domain"
 )
 
-func TestRepository(t *testing.T) {
+func TestInMemoryRepository(t *testing.T) {
 	storage := NewRepository[*domain.Sparkle]()
 
 	t.Run("Save", func(t *testing.T) {
@@ -30,4 +30,21 @@ func TestRepository(t *testing.T) {
 			assert.Equal(t, "because", sparkles[0].Reason)
 		})
 	})
+
+	t.Run("Find", func(t *testing.T) {
+		t.Run("when the entity exists", func(t *testing.T) {
+			sparkle, err := domain.NewSparkle("@tanuki for testing this func")
+			require.NoError(t, err)
+			require.NoError(t, storage.Save(sparkle))
+
+			result := storage.Find(sparkle.ID)
+			require.NotNil(t, result)
+			require.Equal(t, sparkle, result)
+		})
+
+		t.Run("when the entity does not exist", func(t *testing.T) {
+			result := storage.Find("unknown")
+			require.Nil(t, result)
+		})
+	})
 }
diff --git a/pkg/db/repository.go b/pkg/db/repository.go
index 79c7ae3..397eee7 100644
--- a/pkg/db/repository.go
+++ b/pkg/db/repository.go
@@ -1,41 +1,7 @@
 package db
 
-import "gitlab.com/gitlab-org/software-supply-chain-security/authorization/sparkled/pkg/pls"
-
-type Entity interface {
-	GetID() string
-	SetID(id string) error
-	Validate() error
-}
-
 type Repository[T Entity] interface {
 	All() []T
+	Find(string) T
 	Save(T) error
 }
-
-type inMemoryRepository[T Entity] struct {
-	items []T
-}
-
-func NewRepository[T Entity]() Repository[T] {
-	return &inMemoryRepository[T]{
-		items: []T{},
-	}
-}
-
-func (r *inMemoryRepository[T]) All() []T {
-	return r.items
-}
-
-func (r *inMemoryRepository[T]) Save(item T) error {
-	if err := item.Validate(); err != nil {
-		return err
-	}
-
-	if item.GetID() == "" {
-		item.SetID(pls.GenerateULID())
-	}
-
-	r.items = append(r.items, item)
-	return nil
-}