feat: harden multi-user download concurrency

webdav.go

@@ -7,48 +7,63 @@ import (
 )
 
 func (a *App) upload(t *Task) {
+	if t.RemotePath != "" && t.Status == "done" {
+		return
+	}
 	storage, root, enabled := a.storageForTask(t)
 	if !enabled || storage == nil || root == "" {
-		t.Status, t.Progress = "done", 100
-		a.db.Save(t)
-		if err := a.commitCredit(t); err != nil {
-			a.fail(t, err)
-			return
+		if t.Status == "upload_pending" {
+			if err := a.db.Model(t).Updates(map[string]any{
+				"status": "done", "error": "",
+			}).Error; err != nil {
+				return
+			}
+			t.Status, t.Error = "done", ""
 		}
 		return
 	}
-	a.db.Model(t).Updates(map[string]any{"status": "uploading"})
-	remote := strings.TrimRight(root, "/") + "/" + safe(t.Artist) + "/" + safe(t.Album) + "/" + safe(t.Title) + "." + safe(t.Format)
+	if !a.claimUpload(t) {
+		return
+	}
+	remote := strings.TrimRight(root, "/") + "/" + safe(t.Artist) + "/" +
+		safe(t.Album) + "/" + safe(t.Title) + "." + safe(t.Format)
 	if err := storage.MkdirAll(filepath.ToSlash(filepath.Dir(remote))); err != nil {
 		a.failUpload(t, err)
 		return
 	}
-	if fi, err := os.Stat(t.LocalPath); err == nil {
-		if same, _ := storage.ExistsSameSize(remote, fi.Size()); same {
-			t.Status, t.Progress = "done", 100
-			a.db.Save(t)
-			if err := a.commitCredit(t); err != nil {
-				a.fail(t, err)
-				return
-			}
-			a.cleanupLocalFile(t)
+	fi, statErr := os.Stat(t.LocalPath)
+	if statErr != nil {
+		if a.recoverMissingLocalUpload(t) {
 			return
 		}
+		a.failUpload(t, statErr)
+		return
+	}
+	if same, _ := storage.ExistsSameSize(remote, fi.Size()); same {
+		t.RemotePath = remote
+		t.Status, t.Progress, t.Error = "done", 100, ""
+		_ = a.db.Model(t).Updates(map[string]any{
+			"remote_path": remote, "status": "done",
+			"progress": 100, "error": "",
+		}).Error
+		a.cleanupLocalFile(t)
+		return
 	}
 	if err := storage.Upload(t.LocalPath, remote); err != nil {
 		a.failUpload(t, err)
 		return
 	}
 	t.RemotePath = remote
+	t.Status, t.Progress, t.Error = "done", 100, ""
+	if err := a.db.Model(t).Updates(map[string]any{
+		"remote_path": remote, "status": "done",
+		"progress": 100, "error": "",
+	}).Error; err != nil {
+		return
+	}
 	if a.cfg.WebDAVVersionPolicy == "replace_lower" {
 		a.cleanupLowerQualityVersions(t, storage)
 	}
-	t.Status, t.Progress = "done", 100
-	a.db.Save(t)
-	if err := a.commitCredit(t); err != nil {
-		a.fail(t, err)
-		return
-	}
 	a.cleanupLocalFile(t)
 }
 
@@ -56,20 +71,47 @@ func (a *App) cleanupLocalFile(t *Task) {
 	if a.cfg.LocalFilePolicy != "delete_after_upload" || t.LocalPath == "" {
 		return
 	}
+	if t.AssetID != 0 {
+		var pending int64
+		if err := a.db.Model(&Task{}).
+			Where("asset_id = ? AND id <> ? AND local_path = ? AND "+
+				"(status IN ? OR (status = ? AND (remote_path = '' OR remote_path IS NULL)))",
+				t.AssetID, t.ID, t.LocalPath,
+				[]string{"pending", "resolving", "downloading", "uploading", "upload_pending"},
+				"done").Count(&pending).Error; err != nil {
+			return
+		}
+		if pending > 0 {
+			return
+		}
+	}
+
 	if err := os.Remove(t.LocalPath); err != nil && !os.IsNotExist(err) {
 		t.Error = "WebDAV 上传成功，但删除本地文件失败: " + err.Error()
-		a.db.Save(t)
+		_ = a.db.Save(t)
+		return
+	}
+	if t.AssetID != 0 {
+		_ = a.db.Model(&MediaAsset{}).
+			Where("id = ? AND local_path = ?", t.AssetID, t.LocalPath).
+			Updates(map[string]any{
+				"status": "evicted", "local_path": "",
+				"size": 0, "owner_task_id": 0, "lease_until": nil,
+			}).Error
 	}
 }
 
 func (a *App) cleanupLowerQualityVersions(t *Task, storage RemoteStorage) {
-	levels := map[string]int{"standard": 1, "exhigh": 2, "sq": 3, "lossless": 4, "hires": 5, "jyeffect": 6, "sky": 7, "jymaster": 8, "atmos": 9, "atmos_plus": 10, "master": 11}
+	levels := map[string]int{"standard": 1, "exhigh": 2, "sq": 3,
+		"lossless": 4, "hires": 5, "jyeffect": 6, "sky": 7,
+		"jymaster": 8, "atmos": 9, "atmos_plus": 10, "master": 11}
 	current := qualityRank(levels, t.ActualQuality, t.ResolvedQuality, t.Quality)
 	if current == 0 {
 		return
 	}
 	var old []Task
-	a.db.Where("user_id = ? AND artist = ? AND title = ? AND album = ? AND status = ? AND id <> ?", t.UserID, t.Artist, t.Title, t.Album, "done", t.ID).Find(&old)
+	a.db.Where("user_id = ? AND artist = ? AND title = ? AND album = ? "+
+		"AND status = ? AND id <> ?", t.UserID, t.Artist, t.Title, t.Album, "done", t.ID).Find(&old)
 	for _, candidate := range old {
 		q := qualityRank(levels, candidate.ActualQuality, candidate.ResolvedQuality, candidate.Quality)
 		if q == 0 || q >= current || candidate.RemotePath == "" || candidate.RemotePath == t.RemotePath {