first commit

store/store.go

@@ -0,0 +1,48 @@
+package store
+
+import (
+	"context"
+	"crypto/rand"
+	"encoding/hex"
+	"fmt"
+	"time"
+
+	"github.com/redis/go-redis/v9"
+)
+
+// TTL is how long any stored file lives in Redis before automatic deletion.
+const TTL = 2 * time.Hour
+
+type Store struct {
+	rdb *redis.Client
+}
+
+func New(addr string) (*Store, error) {
+	rdb := redis.NewClient(&redis.Options{Addr: addr})
+	if err := rdb.Ping(context.Background()).Err(); err != nil {
+		return nil, fmt.Errorf("redis connect %s: %w", addr, err)
+	}
+	return &Store{rdb: rdb}, nil
+}
+
+// Set stores binary data under key with the global TTL.
+func (s *Store) Set(ctx context.Context, key string, data []byte) error {
+	return s.rdb.Set(ctx, key, data, TTL).Err()
+}
+
+// Get retrieves binary data by key.
+func (s *Store) Get(ctx context.Context, key string) ([]byte, error) {
+	return s.rdb.Get(ctx, key).Bytes()
+}
+
+// Delete removes a key immediately (called after download).
+func (s *Store) Delete(ctx context.Context, key string) {
+	s.rdb.Del(ctx, key)
+}
+
+// NewID generates a random hex ID for use as a Redis key suffix.
+func NewID() string {
+	b := make([]byte, 16)
+	rand.Read(b)
+	return hex.EncodeToString(b)
+}