listing: implement a service layer stub along with tests

1 files changed, 36 insertions, 0 deletions

diff --git a/internal/listing/service.go b/internal/listing/service.go
new file mode 100644
index 0000000..302628b
--- /dev/null
+++ b/internal/listing/service.go
@@ -0,0 +1,36 @@
+package listing
+
+import "log/slog"
+
+type Repository interface {
+	GetAll() ([]Listing, error)
+	GetByCategory(category string) ([]Listing, error)
+}
+
+type Service struct {
+	repository Repository
+}
+
+func New(r Repository) *Service {
+	return &Service{repository: r}
+}
+
+func (s *Service) GetAll() ([]Listing, error) {
+	listings, err := s.repository.GetAll()
+	if err != nil {
+		slog.Error("listing service", "error", err)
+		return nil, err
+	}
+
+	return listings, nil
+}
+
+func (s *Service) GetByCategory(c string) ([]Listing, error) {
+	listings, err := s.repository.GetByCategory(c)
+	if err != nil {
+		slog.Error("listing service", "error", err)
+		return nil, err
+	}
+
+	return listings, nil
+}