Allow admin to associate missing LFS objects for repositories (go-gitea#18143)

This PR reworked the Find pointer files feature in Settings -> LFS page.

When a LFS object is missing from database but exists in LFS content store, admin can associate it to the repository by clicking the Associate button.

This PR is not perfect (because the LFS module itself should be improved too), it's just a nice-to-have feature to help users recover their LFS repositories (eg: database was lost / table was truncated)

Author: wxiaoguang

models/lfs.go

@@ -7,11 +7,13 @@ package models
 import (
 	"context"
 	"errors"
+	"fmt"
 
 	"code.gitea.io/gitea/models/db"
 	repo_model "code.gitea.io/gitea/models/repo"
 	user_model "code.gitea.io/gitea/models/user"
 	"code.gitea.io/gitea/modules/lfs"
+	"code.gitea.io/gitea/modules/log"
 	"code.gitea.io/gitea/modules/timeutil"
 
 	"xorm.io/builder"
@@ -145,6 +147,11 @@ func LFSObjectAccessible(user *user_model.User, oid string) (bool, error) {
 	return count > 0, err
 }
 
+// LFSObjectIsAssociated checks if a provided Oid is associated
+func LFSObjectIsAssociated(oid string) (bool, error) {
+	return db.GetEngine(db.DefaultContext).Exist(&LFSMetaObject{Pointer: lfs.Pointer{Oid: oid}})
+}
+
 // LFSAutoAssociate auto associates accessible LFSMetaObjects
 func LFSAutoAssociate(metas []*LFSMetaObject, user *user_model.User, repoID int64) error {
 	ctx, committer, err := db.TxContext()
@@ -162,23 +169,39 @@ func LFSAutoAssociate(metas []*LFSMetaObject, user *user_model.User, repoID int6
 		oidMap[meta.Oid] = meta
 	}
 
-	cond := builder.NewCond()
 	if !user.IsAdmin {
-		cond = builder.In("`lfs_meta_object`.repository_id",
-			builder.Select("`repository`.id").From("repository").Where(accessibleRepositoryCondition(user)))
-	}
-	newMetas := make([]*LFSMetaObject, 0, len(metas))
-	if err := sess.Cols("oid").Where(cond).In("oid", oids...).GroupBy("oid").Find(&newMetas); err != nil {
-		return err
-	}
-	for i := range newMetas {
-		newMetas[i].Size = oidMap[newMetas[i].Oid].Size
-		newMetas[i].RepositoryID = repoID
-	}
-	if err := db.Insert(ctx, newMetas); err != nil {
-		return err
+		newMetas := make([]*LFSMetaObject, 0, len(metas))
+		cond := builder.In(
+			"`lfs_meta_object`.repository_id",
+			builder.Select("`repository`.id").From("repository").Where(accessibleRepositoryCondition(user)),
+		)
+		err = sess.Cols("oid").Where(cond).In("oid", oids...).GroupBy("oid").Find(&newMetas)
+		if err != nil {
+			return err
+		}
+		if len(newMetas) != len(oidMap) {
+			return fmt.Errorf("unable collect all LFS objects from database, expected %d, actually %d", len(oidMap), len(newMetas))
+		}
+		for i := range newMetas {
+			newMetas[i].Size = oidMap[newMetas[i].Oid].Size
+			newMetas[i].RepositoryID = repoID
+		}
+		if err = db.Insert(ctx, newMetas); err != nil {
+			return err
+		}
+	} else {
+		// admin can associate any LFS object to any repository, and we do not care about errors (eg: duplicated unique key),
+		// even if error occurs, it won't hurt users and won't make things worse
+		for i := range metas {
+			_, err = sess.Insert(&LFSMetaObject{
+				Pointer:      lfs.Pointer{Oid: metas[i].Oid, Size: metas[i].Size},
+				RepositoryID: repoID,
+			})
+			if err != nil {
+				log.Warn("failed to insert LFS meta object into database, err=%v", err)
+			}
+		}
 	}
-
 	return committer.Commit()
 }
 

routers/web/repo/lfs.go

@@ -421,12 +421,13 @@ func LFSPointerFiles(ctx *context.Context) {
 		var numAssociated, numNoExist, numAssociatable int
 
 		type pointerResult struct {
-			SHA        string
-			Oid        string
-			Size       int64
-			InRepo     bool
-			Exists     bool
-			Accessible bool
+			SHA          string
+			Oid          string
+			Size         int64
+			InRepo       bool
+			Exists       bool
+			Accessible   bool
+			Associatable bool
 		}
 
 		results := []pointerResult{}
@@ -461,22 +462,29 @@ func LFSPointerFiles(ctx *context.Context) {
 					// Can we fix?
 					// OK well that's "simple"
 					// - we need to check whether current user has access to a repo that has access to the file
-					result.Accessible, err = models.LFSObjectAccessible(ctx.User, pointerBlob.Oid)
+					result.Associatable, err = models.LFSObjectAccessible(ctx.User, pointerBlob.Oid)
 					if err != nil {
 						return err
 					}
-				} else {
-					result.Accessible = true
+					if !result.Associatable {
+						associated, err := models.LFSObjectIsAssociated(pointerBlob.Oid)
+						if err != nil {
+							return err
+						}
+						result.Associatable = !associated
+					}
 				}
 			}
 
+			result.Accessible = result.InRepo || result.Associatable
+
 			if result.InRepo {
 				numAssociated++
 			}
 			if !result.Exists {
 				numNoExist++
 			}
-			if !result.InRepo && result.Accessible {
+			if result.Associatable {
 				numAssociatable++
 			}
 

templates/repo/settings/lfs_pointers.tmpl

@@ -11,7 +11,7 @@
 					<form class="ui form" method="post" action="{{$.Link}}/associate">
 						{{.CsrfTokenHtml}}
 						{{range .Pointers}}
-							{{if and (not .InRepo) .Exists .Accessible}}
+							{{if .Associatable}}
 								<input type="hidden" name="oid" value="{{.Oid}} {{.Size}}"/>
 							{{end}}
 						{{end}}