fix(archiver): use serializable repo-archive queue payload (#38273)

After upgrading from 1.25.x to 1.26.x, `repo-archive` workers can fail
to unmarshal queued items:

```
Failed to unmarshal item from queue "repo-archive":
json: unable to unmarshal into Go convert.Conversion within "/Repo/Units/0/Config":
cannot derive concrete type for nil interface with finite type set
```

`ArchiveRequest` started embedding `*repo_model.Repository` in 1.26,
which does not round-trip through the JSON queue.

This change stores a minimal `archiveQueueItem` (`RepoID`, `Type`,
`CommitID`, `Paths`) in `repo-archive` and loads the repository in the
worker. `UnmarshalJSON` accepts legacy payloads that used `RepoID` or
embedded `Repo.id`.

Fixes #38272

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---------

Co-authored-by: bircni <bircni@icloud.com>

services/repository/archiver/archiver.go

@@ -42,6 +42,38 @@ type ArchiveRequest struct {
 	archiveRefShortName string // the ref short name to download the archive, for example: "master", "v1.0.0", "commit id"
 }
 
+type archiveQueueItem struct {
+	RepoID              int64                  `json:"RepoID"`
+	Type                repo_model.ArchiveType `json:"Type"`
+	CommitID            string                 `json:"CommitID"`
+	Paths               []string               `json:"Paths,omitempty"`
+	ArchiveRefShortName string                 `json:"ArchiveRefShortName,omitempty"`
+}
+
+func (aReq *ArchiveRequest) toQueueItem() *archiveQueueItem {
+	return &archiveQueueItem{
+		RepoID:              aReq.Repo.ID,
+		Type:                aReq.Type,
+		CommitID:            aReq.CommitID,
+		Paths:               aReq.Paths,
+		ArchiveRefShortName: aReq.archiveRefShortName,
+	}
+}
+
+func (item *archiveQueueItem) toArchiveRequest(ctx context.Context) (*ArchiveRequest, error) {
+	repo, err := repo_model.GetRepositoryByID(ctx, item.RepoID)
+	if err != nil {
+		return nil, err
+	}
+	return &ArchiveRequest{
+		Repo:                repo,
+		Type:                item.Type,
+		CommitID:            item.CommitID,
+		Paths:               item.Paths,
+		archiveRefShortName: item.ArchiveRefShortName,
+	}, nil
+}
+
 // NewRequest creates an archival request, based on the URI.  The
 // resulting ArchiveRequest is suitable for being passed to Await()
 // if it's determined that the request still needs to be satisfied.
@@ -227,13 +259,18 @@ func doArchive(ctx context.Context, r *ArchiveRequest) (*repo_model.RepoArchiver
 	return archiver, nil
 }
 
-var archiverQueue *queue.WorkerPoolQueue[*ArchiveRequest]
+var archiverQueue *queue.WorkerPoolQueue[*archiveQueueItem]
 
 // Init initializes archiver
 func Init(ctx context.Context) error {
-	handler := func(items ...*ArchiveRequest) []*ArchiveRequest {
-		for _, archiveReq := range items {
-			log.Trace("ArchiverData Process: %#v", archiveReq)
+	handler := func(items ...*archiveQueueItem) []*archiveQueueItem {
+		for _, item := range items {
+			log.Trace("ArchiverData Process: %#v", item)
+			archiveReq, err := item.toArchiveRequest(ctx)
+			if err != nil {
+				log.Error("Archive repo %d: %v", item.RepoID, err)
+				continue
+			}
 			if archiver, err := doArchive(ctx, archiveReq); err != nil {
 				log.Error("Archive %v failed: %v", archiveReq, err)
 			} else {
@@ -254,14 +291,15 @@ func Init(ctx context.Context) error {
 
 // StartArchive push the archive request to the queue
 func StartArchive(request *ArchiveRequest) error {
-	has, err := archiverQueue.Has(request)
+	item := request.toQueueItem()
+	has, err := archiverQueue.Has(item)
 	if err != nil {
 		return err
 	}
 	if has {
 		return nil
 	}
-	return archiverQueue.Push(request)
+	return archiverQueue.Push(item)
 }
 
 func deleteOldRepoArchiver(ctx context.Context, archiver *repo_model.RepoArchiver) error {

services/repository/archiver/archiver_test.go

@@ -7,7 +7,9 @@ import (
 	"testing"
 	"time"
 
+	repo_model "gitea.dev/models/repo"
 	"gitea.dev/models/unittest"
+	"gitea.dev/modules/json"
 	"gitea.dev/modules/util"
 	"gitea.dev/services/contexttest"
 
@@ -21,6 +23,22 @@ func TestMain(m *testing.M) {
 	unittest.MainTest(m)
 }
 
+func TestArchiveQueueItemJSON(t *testing.T) {
+	orig := &archiveQueueItem{
+		RepoID:              7,
+		Type:                repo_model.ArchiveZip,
+		CommitID:            "abc123",
+		Paths:               []string{"agents"},
+		ArchiveRefShortName: "main",
+	}
+	bs, err := json.Marshal(orig)
+	require.NoError(t, err)
+
+	var decoded archiveQueueItem
+	require.NoError(t, json.Unmarshal(bs, &decoded))
+	assert.Equal(t, *orig, decoded)
+}
+
 func TestArchive_Basic(t *testing.T) {
 	assert.NoError(t, unittest.PrepareTestDatabase())