feat(storage): 实现本地存储功能，包括文件上传和下载接口

backend/app/jobs/media_process_job.go

@@ -2,17 +2,23 @@ package jobs
 
 import (
 	"context"
+	"fmt"
+	"os/exec"
+	"path/filepath"
 	"time"
 
 	"github.com/riverqueue/river"
+	log "github.com/sirupsen/logrus"
 	"quyun/v2/app/jobs/args"
 	"quyun/v2/database/models"
 	"quyun/v2/pkg/consts"
+	"quyun/v2/providers/storage"
 )
 
 // @provider(job)
 type MediaProcessWorker struct {
 	river.WorkerDefaults[args.MediaProcessArgs]
+	storage *storage.Storage
 }
 
 func (j *MediaProcessWorker) Work(ctx context.Context, job *river.Job[args.MediaProcessArgs]) error {
@@ -23,14 +29,41 @@ func (j *MediaProcessWorker) Work(ctx context.Context, job *river.Job[args.Media
 		return err
 	}
 
-	// 2. Mock Processing
-	// Update status to processing
+	// 2. Update status to processing
 	_, err = models.MediaAssetQuery.WithContext(ctx).Where(models.MediaAssetQuery.ID.Eq(asset.ID)).UpdateSimple(models.MediaAssetQuery.Status.Value(consts.MediaAssetStatusProcessing))
 	if err != nil {
 		return err
 	}
 
-	// 3. Update status to ready
+	// 3. Process Video (FFmpeg)
+	if asset.Type == consts.MediaAssetTypeVideo {
+		if _, err := exec.LookPath("ffmpeg"); err == nil {
+			localPath := j.storage.Config.LocalPath
+			if localPath == "" {
+				localPath = "./storage"
+			}
+			inputFile := filepath.Join(localPath, asset.ObjectKey)
+			outputDir := filepath.Dir(inputFile)
+			// Simple transcoding: convert to MP4 (mocking complex HLS for simplicity)
+			// Or just extract cover
+			coverKey := asset.ObjectKey + ".jpg"
+			coverFile := filepath.Join(outputDir, filepath.Base(coverKey))
+
+			// Generate Cover
+			cmd := exec.CommandContext(ctx, "ffmpeg", "-y", "-i", inputFile, "-ss", "00:00:01.000", "-vframes", "1", coverFile)
+			if out, err := cmd.CombinedOutput(); err != nil {
+				log.Errorf("ffmpeg failed: %s, output: %s", err, string(out))
+				// Don't fail the job, just skip cover
+			} else {
+				log.Infof("Generated cover: %s", coverFile)
+				// TODO: Create MediaAsset for cover? Or update meta?
+			}
+		} else {
+			log.Warn("ffmpeg not found, skipping real transcoding")
+		}
+	}
+
+	// 4. Update status to ready
 	_, err = models.MediaAssetQuery.WithContext(ctx).Where(models.MediaAssetQuery.ID.Eq(asset.ID)).Updates(&models.MediaAsset{
 		Status:    consts.MediaAssetStatusReady,
 		UpdatedAt: time.Now(),