some type stubs

storage.go

@@ -0,0 +1,37 @@
+package main
+
+import (
+	"context"
+	"errors"
+)
+
+var (
+	ErrNotFound = errors.New("not found")
+)
+
+type Storage struct {
+	driver Driver
+}
+
+func NewTestStorage() Storage {
+	return Storage{driver: NewTestDB()}
+}
+
+func NewStorage(driver Driver) Storage {
+	return Storage{driver: driver}
+}
+
+func (s Storage) Upsert(ctx context.Context, m Message) error {
+	return s.driver.Set(ctx, "storage", m.ID, m.Serialize())
+}
+
+func (s Storage) Get(ctx context.Context, id string) (Message, error) {
+	b, err := s.driver.Get(ctx, "storage", id)
+	if err != nil {
+		return Message{}, err
+	}
+	if b == nil {
+		return Message{}, ErrNotFound
+	}
+	return MustDeserialize(b), nil
+}