更新

im/backend/internal/app/media_batch.go

@@ -0,0 +1,64 @@
+package app
+
+import (
+	"context"
+	"fmt"
+	"io"
+	"os"
+	"path/filepath"
+	"time"
+)
+
+type mediaUploadObject struct {
+	Key, ContentType string
+	Size             int64
+	Body             io.Reader
+}
+
+type localMediaStorage struct{ directory string }
+
+func (s localMediaStorage) Bucket() string { return "" }
+func (s localMediaStorage) Put(_ context.Context, key, _ string, _ int64, body io.Reader) error {
+	if err := os.MkdirAll(s.directory, 0o755); err != nil {
+		return err
+	}
+	target := filepath.Join(s.directory, filepath.Base(key))
+	file, err := os.OpenFile(target, os.O_CREATE|os.O_EXCL|os.O_WRONLY, 0o644)
+	if err != nil {
+		return err
+	} // Never remove an existing file on collision.
+	_, copyErr := io.Copy(file, body)
+	closeErr := file.Close()
+	if copyErr != nil || closeErr != nil {
+		_ = os.Remove(target)
+		if copyErr != nil {
+			return copyErr
+		}
+		return closeErr
+	}
+	return nil
+}
+func (s localMediaStorage) Delete(_ context.Context, key string) error {
+	return os.Remove(filepath.Join(s.directory, filepath.Base(key)))
+}
+
+// Return a cleanup function for both a partially failed upload and a failed DB
+// finalization. Cleanup gets its own deadline even if the HTTP client cancels.
+func putMediaObjects(ctx context.Context, storage mediaObjectStorage, objects []mediaUploadObject) (func(), error) {
+	var uploaded []string
+	cleanup := func() {
+		cleanupCtx, cancel := context.WithTimeout(context.WithoutCancel(ctx), 15*time.Second)
+		defer cancel()
+		for i := len(uploaded) - 1; i >= 0; i-- {
+			_ = storage.Delete(cleanupCtx, uploaded[i])
+		}
+	}
+	for _, object := range objects {
+		if err := storage.Put(ctx, object.Key, object.ContentType, object.Size, object.Body); err != nil {
+			cleanup()
+			return func() {}, fmt.Errorf("store media object: %w", err)
+		}
+		uploaded = append(uploaded, object.Key)
+	}
+	return cleanup, nil
+}