feat: generate media cover assets

backend/app/jobs/media_process_job.go

@@ -2,20 +2,26 @@ package jobs
 
 import (
 	"context"
+	"crypto/md5"
+	"encoding/hex"
 	"errors"
+	"io"
 	"os"
 	"os/exec"
+	"path"
 	"path/filepath"
 	"strings"
 	"time"
 
 	"quyun/v2/app/jobs/args"
+	"quyun/v2/database/fields"
 	"quyun/v2/database/models"
 	"quyun/v2/pkg/consts"
 	"quyun/v2/providers/storage"
 
 	"github.com/riverqueue/river"
 	log "github.com/sirupsen/logrus"
+	"go.ipao.vip/gen/types"
 	"gorm.io/gorm"
 )
 
@@ -74,8 +80,8 @@ func (j *MediaProcessWorker) Work(ctx context.Context, job *river.Job[args.Media
 				log.Warn("ffmpeg not found, skipping real transcoding")
 			} else {
 				outputDir := filepath.Dir(inputFile)
-				coverKey := asset.ObjectKey + ".jpg"
-				coverFile := filepath.Join(outputDir, filepath.Base(coverKey))
+				coverTempKey := asset.ObjectKey + ".jpg"
+				coverFile := filepath.Join(outputDir, filepath.Base(coverTempKey))
 
 				// 生成封面，作为后续管线的占位输出。
 				cmd := exec.CommandContext(
@@ -95,7 +101,11 @@ func (j *MediaProcessWorker) Work(ctx context.Context, job *river.Job[args.Media
 					finalStatus = consts.MediaAssetStatusFailed
 				} else {
 					log.Infof("Generated cover: %s", coverFile)
-					// TODO: 生成封面资产或写入 meta，由后续管线接管。
+					// 生成封面资产记录，便于后台可追踪产物。
+					if err := j.registerCoverAsset(ctx, asset, coverFile); err != nil {
+						log.Errorf("register cover failed: %s", err)
+						finalStatus = consts.MediaAssetStatusFailed
+					}
 				}
 			}
 		} else {
@@ -112,3 +122,118 @@ func (j *MediaProcessWorker) Work(ctx context.Context, job *river.Job[args.Media
 		})
 	return err
 }
+
+func (j *MediaProcessWorker) registerCoverAsset(ctx context.Context, asset *models.MediaAsset, coverFile string) error {
+	if asset == nil || coverFile == "" {
+		return nil
+	}
+	if _, err := os.Stat(coverFile); err != nil {
+		return err
+	}
+
+	// 已存在封面派生资产时直接跳过。
+	tbl, q := models.MediaAssetQuery.QueryContext(ctx)
+	existing, err := q.Where(
+		tbl.SourceAssetID.Eq(asset.ID),
+		tbl.Type.Eq(consts.MediaAssetTypeImage),
+	).First()
+	if err == nil && existing != nil {
+		return nil
+	}
+	if err != nil && !errors.Is(err, gorm.ErrRecordNotFound) {
+		return err
+	}
+
+	hash, size, err := fileMD5(coverFile)
+	if err != nil {
+		return err
+	}
+
+	var tenant *models.Tenant
+	if asset.TenantID > 0 {
+		tenant, err = models.TenantQuery.WithContext(ctx).
+			Where(models.TenantQuery.ID.Eq(asset.TenantID)).
+			First()
+		if err != nil && !errors.Is(err, gorm.ErrRecordNotFound) {
+			return err
+		}
+	}
+
+	filename := asset.Meta.Data().Filename
+	if filename == "" {
+		filename = filepath.Base(asset.ObjectKey)
+	}
+	coverName := coverFilename(filename)
+	objectKey := buildObjectKey(tenant, hash, coverName)
+
+	// 本地存储将文件移动到目标 objectKey 位置，保持路径规范。
+	localPath := j.storage.Config.LocalPath
+	if localPath == "" {
+		localPath = "./storage"
+	}
+	dstPath := filepath.Join(localPath, filepath.FromSlash(objectKey))
+	if coverFile != dstPath {
+		if err := os.MkdirAll(filepath.Dir(dstPath), 0o755); err != nil {
+			return err
+		}
+		if _, err := os.Stat(dstPath); err == nil {
+			_ = os.Remove(coverFile)
+		} else if err := os.Rename(coverFile, dstPath); err != nil {
+			return err
+		}
+	}
+
+	coverAsset := &models.MediaAsset{
+		TenantID:      asset.TenantID,
+		UserID:        asset.UserID,
+		Type:          consts.MediaAssetTypeImage,
+		Status:        consts.MediaAssetStatusReady,
+		Provider:      asset.Provider,
+		Bucket:        asset.Bucket,
+		ObjectKey:     objectKey,
+		Hash:          hash,
+		Variant:       consts.MediaAssetVariantMain,
+		SourceAssetID: asset.ID,
+		Meta: types.NewJSONType(fields.MediaAssetMeta{
+			Filename: coverName,
+			Size:     size,
+		}),
+	}
+	if err := models.MediaAssetQuery.WithContext(ctx).Create(coverAsset); err != nil {
+		return err
+	}
+	return nil
+}
+
+func coverFilename(filename string) string {
+	base := strings.TrimSuffix(filename, filepath.Ext(filename))
+	if base == "" {
+		base = "cover"
+	}
+	return base + "_cover.jpg"
+}
+
+func buildObjectKey(tenant *models.Tenant, hash, filename string) string {
+	// 按租户维度组织对象路径：quyun/<tenant_uuid>/<hash>.<ext>
+	tenantUUID := "public"
+	if tenant != nil && tenant.UUID.String() != "" {
+		tenantUUID = tenant.UUID.String()
+	}
+	ext := strings.ToLower(filepath.Ext(filename))
+	return path.Join("quyun", tenantUUID, hash+ext)
+}
+
+func fileMD5(filename string) (string, int64, error) {
+	f, err := os.Open(filename)
+	if err != nil {
+		return "", 0, err
+	}
+	defer f.Close()
+
+	h := md5.New()
+	size, err := io.Copy(h, f)
+	if err != nil {
+		return "", size, err
+	}
+	return hex.EncodeToString(h.Sum(nil)), size, nil
+}

docs/todo_list.md

@@ -268,6 +268,7 @@
 - Worker：从对象存储下载源文件到临时目录 → FFmpeg 处理 → 结果上传回对象存储 → 清理临时文件。
 - 产物：封面/预览片段自动生成并回写 `media_assets`。
 - 本地 FS 仍保留兼容路径（开发/测试使用）。
+ - 进度：本地视频处理已可生成封面资产（ffmpeg 可用时）。
 
 **测试方案**
 - 对象存储模式下上传视频触发处理，封面/预览可访问；任务异常可重试。