fix: ensure consistent empty repository topics field (#7920)

Resolves #7878

An empty repository topic was not stored consistently across databases, this caused the `ONLY_SHOW_RELEVANT_REPOS` feature to not work correctly. Always store empty repository topics as an empty array to fix this.

Reviewed-on: https://codeberg.org/forgejo/forgejo/pulls/7920
Reviewed-by: Gusted <gusted@noreply.codeberg.org>
Co-authored-by: Maks1mS <maks1ms@noreply.codeberg.org>
Co-committed-by: Maks1mS <maks1ms@noreply.codeberg.org>

models/fixtures/repository.yml

@@ -31,6 +31,8 @@
   close_issues_via_commit_in_any_branch: false
   created_unix: 1731254961
   updated_unix: 1731254961
+  topics: '[]'
+  
 -
   id: 2
   owner_id: 2
@@ -61,7 +63,7 @@
   size: 0
   is_fsck_enabled: true
   close_issues_via_commit_in_any_branch: true
-
+  topics: '[]'
 -
   id: 3
   owner_id: 3
@@ -94,6 +96,7 @@
   close_issues_via_commit_in_any_branch: false
   created_unix: 1700000001
   updated_unix: 1700000001
+  topics: '[]'
 
 -
   id: 4
@@ -125,6 +128,7 @@
   size: 0
   is_fsck_enabled: true
   close_issues_via_commit_in_any_branch: false
+  topics: '[]'
 
 -
   id: 5
@@ -158,6 +162,7 @@
   close_issues_via_commit_in_any_branch: false
   created_unix: 1700000002
   updated_unix: 1700000002
+  topics: '[]'
 
 -
   id: 6
@@ -190,6 +195,7 @@
   close_issues_via_commit_in_any_branch: false
   created_unix: 1710000001
   updated_unix: 1710000001
+  topics: '[]'
 
 -
   id: 7
@@ -222,6 +228,7 @@
   close_issues_via_commit_in_any_branch: false
   created_unix: 1710000003
   updated_unix: 1710000003
+  topics: '[]'
 
 -
   id: 8
@@ -254,6 +261,7 @@
   close_issues_via_commit_in_any_branch: false
   created_unix: 1710000002
   updated_unix: 1710000002
+  topics: '[]'
 
 -
   id: 9
@@ -284,6 +292,7 @@
   size: 0
   is_fsck_enabled: true
   close_issues_via_commit_in_any_branch: false
+  topics: '[]'
 
 -
   id: 10
@@ -315,6 +324,7 @@
   size: 0
   is_fsck_enabled: true
   close_issues_via_commit_in_any_branch: false
+  topics: '[]'
 
 -
   id: 11
@@ -346,6 +356,7 @@
   size: 0
   is_fsck_enabled: true
   close_issues_via_commit_in_any_branch: false
+  topics: '[]'
 
 -
   id: 12
@@ -376,6 +387,7 @@
   size: 0
   is_fsck_enabled: true
   close_issues_via_commit_in_any_branch: false
+  topics: '[]'
 
 -
   id: 13
@@ -406,6 +418,7 @@
   size: 0
   is_fsck_enabled: true
   close_issues_via_commit_in_any_branch: false
+  topics: '[]'
 
 -
   id: 14
@@ -437,6 +450,7 @@
   size: 0
   is_fsck_enabled: true
   close_issues_via_commit_in_any_branch: false
+  topics: '[]'
 
 -
   id: 15
@@ -468,6 +482,7 @@
   size: 0
   is_fsck_enabled: true
   close_issues_via_commit_in_any_branch: false
+  topics: '[]'
 
 -
   id: 16
@@ -499,6 +514,7 @@
   size: 0
   is_fsck_enabled: true
   close_issues_via_commit_in_any_branch: false
+  topics: '[]'
 
 -
   id: 17
@@ -529,6 +545,7 @@
   size: 0
   is_fsck_enabled: true
   close_issues_via_commit_in_any_branch: false
+  topics: '[]'
 
 -
   id: 18
@@ -559,6 +576,7 @@
   size: 0
   is_fsck_enabled: true
   close_issues_via_commit_in_any_branch: false
+  topics: '[]'
 
 -
   id: 19
@@ -589,6 +607,7 @@
   size: 0
   is_fsck_enabled: true
   close_issues_via_commit_in_any_branch: false
+  topics: '[]'
 
 -
   id: 20
@@ -619,6 +638,7 @@
   size: 0
   is_fsck_enabled: true
   close_issues_via_commit_in_any_branch: false
+  topics: '[]'
 
 -
   id: 21
@@ -649,6 +669,7 @@
   size: 0
   is_fsck_enabled: true
   close_issues_via_commit_in_any_branch: false
+  topics: '[]'
 
 -
   id: 22
@@ -679,6 +700,7 @@
   size: 0
   is_fsck_enabled: true
   close_issues_via_commit_in_any_branch: false
+  topics: '[]'
 
 -
   id: 23
@@ -709,6 +731,7 @@
   size: 0
   is_fsck_enabled: true
   close_issues_via_commit_in_any_branch: false
+  topics: '[]'
 
 -
   id: 24
@@ -739,6 +762,7 @@
   size: 0
   is_fsck_enabled: true
   close_issues_via_commit_in_any_branch: false
+  topics: '[]'
 
 -
   id: 25
@@ -769,6 +793,7 @@
   size: 0
   is_fsck_enabled: true
   close_issues_via_commit_in_any_branch: false
+  topics: '[]'
 
 -
   id: 26
@@ -799,6 +824,7 @@
   size: 0
   is_fsck_enabled: true
   close_issues_via_commit_in_any_branch: false
+  topics: '[]'
 
 -
   id: 27
@@ -829,6 +855,7 @@
   size: 0
   is_fsck_enabled: true
   close_issues_via_commit_in_any_branch: false
+  topics: '[]'
 
 -
   id: 28
@@ -859,6 +886,7 @@
   size: 0
   is_fsck_enabled: true
   close_issues_via_commit_in_any_branch: false
+  topics: '[]'
 
 -
   id: 29
@@ -889,6 +917,7 @@
   size: 0
   is_fsck_enabled: true
   close_issues_via_commit_in_any_branch: false
+  topics: '[]'
 
 -
   id: 30
@@ -919,6 +948,7 @@
   size: 0
   is_fsck_enabled: true
   close_issues_via_commit_in_any_branch: false
+  topics: '[]'
 
 -
   id: 31
@@ -950,6 +980,7 @@
   size: 0
   is_fsck_enabled: true
   close_issues_via_commit_in_any_branch: false
+  topics: '[]'
 
 -
   id: 32 # org public repo
@@ -982,6 +1013,7 @@
   close_issues_via_commit_in_any_branch: false
   created_unix: 1700000003
   updated_unix: 1700000003
+  topics: '[]'
 
 -
   id: 33
@@ -1013,6 +1045,7 @@
   size: 0
   is_fsck_enabled: true
   close_issues_via_commit_in_any_branch: false
+  topics: '[]'
 
 -
   id: 34
@@ -1043,6 +1076,7 @@
   size: 0
   is_fsck_enabled: true
   close_issues_via_commit_in_any_branch: false
+  topics: '[]'
 
 -
   id: 35
@@ -1073,6 +1107,7 @@
   size: 0
   is_fsck_enabled: true
   close_issues_via_commit_in_any_branch: false
+  topics: '[]'
 
 -
   id: 36
@@ -1104,6 +1139,7 @@
   size: 0
   is_fsck_enabled: true
   close_issues_via_commit_in_any_branch: false
+  topics: '[]'
 
 -
   id: 37
@@ -1135,6 +1171,7 @@
   size: 0
   is_fsck_enabled: true
   close_issues_via_commit_in_any_branch: false
+  topics: '[]'
 
 -
   id: 38
@@ -1166,6 +1203,7 @@
   size: 0
   is_fsck_enabled: true
   close_issues_via_commit_in_any_branch: false
+  topics: '[]'
 
 -
   id: 39
@@ -1197,6 +1235,7 @@
   size: 0
   is_fsck_enabled: true
   close_issues_via_commit_in_any_branch: false
+  topics: '[]'
 
 -
   id: 40
@@ -1228,6 +1267,7 @@
   size: 0
   is_fsck_enabled: true
   close_issues_via_commit_in_any_branch: false
+  topics: '[]'
 
 -
   id: 41
@@ -1259,6 +1299,7 @@
   size: 0
   is_fsck_enabled: true
   close_issues_via_commit_in_any_branch: false
+  topics: '[]'
 
 -
   id: 42
@@ -1290,6 +1331,7 @@
   size: 0
   is_fsck_enabled: true
   close_issues_via_commit_in_any_branch: false
+  topics: '[]'
 
 -
   id: 43
@@ -1320,6 +1362,7 @@
   size: 0
   is_fsck_enabled: true
   close_issues_via_commit_in_any_branch: false
+  topics: '[]'
 
 -
   id: 44
@@ -1351,6 +1394,7 @@
   size: 0
   is_fsck_enabled: true
   close_issues_via_commit_in_any_branch: false
+  topics: '[]'
 
 -
   id: 45
@@ -1381,6 +1425,7 @@
   size: 0
   is_fsck_enabled: true
   close_issues_via_commit_in_any_branch: false
+  topics: '[]'
 
 -
   id: 46
@@ -1412,6 +1457,7 @@
   size: 0
   is_fsck_enabled: true
   close_issues_via_commit_in_any_branch: false
+  topics: '[]'
 
 -
   id: 47
@@ -1443,6 +1489,7 @@
   size: 0
   is_fsck_enabled: true
   close_issues_via_commit_in_any_branch: false
+  topics: '[]'
 
 -
   id: 48
@@ -1474,6 +1521,7 @@
   size: 0
   is_fsck_enabled: true
   close_issues_via_commit_in_any_branch: false
+  topics: '[]'
 
 -
   id: 49
@@ -1506,6 +1554,7 @@
   size: 0
   is_fsck_enabled: true
   close_issues_via_commit_in_any_branch: false
+  topics: '[]'
 
 -
   id: 50
@@ -1537,6 +1586,7 @@
   size: 0
   is_fsck_enabled: true
   close_issues_via_commit_in_any_branch: false
+  topics: '[]'
 
 -
   id: 51
@@ -1568,6 +1618,7 @@
   size: 0
   is_fsck_enabled: true
   close_issues_via_commit_in_any_branch: false
+  topics: '[]'
 
 -
   id: 52
@@ -1599,6 +1650,7 @@
   size: 0
   is_fsck_enabled: true
   close_issues_via_commit_in_any_branch: false
+  topics: '[]'
 
 -
   id: 53
@@ -1627,6 +1679,7 @@
   size: 0
   is_fsck_enabled: true
   close_issues_via_commit_in_any_branch: false
+  topics: '[]'
 
 -
   id: 54
@@ -1639,6 +1692,7 @@
   is_archived: false
   is_private: true
   status: 0
+  topics: '[]'
 
 -
   id: 55
@@ -1651,6 +1705,7 @@
   is_private: true
   num_issues: 1
   status: 0
+  topics: '[]'
 
 -
   id: 56
@@ -1664,6 +1719,7 @@
   is_private: true
   status: 0
   num_issues: 0
+  topics: '[]'
 
 -
   id: 57
@@ -1677,6 +1733,7 @@
   is_private: false
   status: 0
   num_issues: 0
+  topics: '[]'
 
 -
   id: 58 # org public repo
@@ -1708,6 +1765,7 @@
   size: 0
   is_fsck_enabled: true
   close_issues_via_commit_in_any_branch: false
+  topics: '[]'
 
 -
   id: 1059
@@ -1721,6 +1779,7 @@
   is_private: false
   status: 0
   num_issues: 0
+  topics: '[]'
 
 -
   id: 59
@@ -1734,6 +1793,7 @@
   is_private: true
   status: 0
   num_issues: 0
+  topics: '[]'
 
 -
   id: 60
@@ -1765,6 +1825,7 @@
   size: 0
   is_fsck_enabled: true
   close_issues_via_commit_in_any_branch: false
+  topics: '[]'
 
 -
   id: 61
@@ -1796,6 +1857,7 @@
   size: 0
   is_fsck_enabled: true
   close_issues_via_commit_in_any_branch: false
+  topics: '[]'
 
 - id: 62
   owner_id: 2
@@ -1826,3 +1888,4 @@
   size: 0
   is_fsck_enabled: true
   close_issues_via_commit_in_any_branch: false
+  topics: '[]'

models/forgejo_migrations/migrate.go

@@ -99,6 +99,8 @@ var migrations = []*Migration{
 	NewMigration("Add public key information to `FederatedUser` and `FederationHost`", AddPublicKeyInformationForFederation),
 	// v29 -> v30
 	NewMigration("Migrate `User.NormalizedFederatedURI` column to extract port & schema into FederatedHost", MigrateNormalizedFederatedURI),
+	// v30 -> v31
+	NewMigration("Normalize repository.topics to empty slice instead of null", SetTopicsAsEmptySlice),
 }
 
 // GetCurrentDBVersion returns the current Forgejo database version.

models/forgejo_migrations/v31.go

@@ -0,0 +1,29 @@
+// Copyright 2025 The Forgejo Authors.
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+package forgejo_migrations //nolint:revive
+
+import (
+	"xorm.io/xorm"
+	"xorm.io/xorm/schemas"
+)
+
+func SetTopicsAsEmptySlice(x *xorm.Engine) error {
+	var err error
+	if x.Dialect().URI().DBType == schemas.POSTGRES {
+		_, err = x.Exec("UPDATE `repository` SET topics = '[]' WHERE topics IS NULL OR topics::text = 'null'")
+	} else {
+		_, err = x.Exec("UPDATE `repository` SET topics = '[]' WHERE topics IS NULL")
+	}
+
+	if err != nil {
+		return err
+	}
+
+	type Repository struct {
+		ID     int64    `xorm:"pk autoincr"`
+		Topics []string `xorm:"TEXT JSON NOT NULL"`
+	}
+
+	return x.Sync(new(Repository))
+}

models/forgejo_migrations/v31_test.go

@@ -0,0 +1,38 @@
+// Copyright 2025 The Forgejo Authors.
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+package forgejo_migrations //nolint:revive
+
+import (
+	"testing"
+
+	migration_tests "forgejo.org/models/migrations/test"
+
+	"github.com/stretchr/testify/require"
+)
+
+func Test_SetTopicsAsEmptySlice(t *testing.T) {
+	type Repository struct {
+		ID     int64    `xorm:"pk autoincr"`
+		Topics []string `xorm:"TEXT JSON"`
+	}
+
+	x, deferable := migration_tests.PrepareTestEnv(t, 0, new(Repository))
+	defer deferable()
+	if x == nil || t.Failed() {
+		return
+	}
+
+	require.NoError(t, SetTopicsAsEmptySlice(x))
+
+	var repos []Repository
+	require.NoError(t, x.Find(&repos))
+
+	for _, repo := range repos {
+		if repo.ID == 2 {
+			require.Equal(t, []string{"go", "dev"}, repo.Topics, "Valid topics should remain unchanged")
+		} else {
+			require.Equal(t, []string{}, repo.Topics, "NULL topics should be set to empty array")
+		}
+	}
+}

models/migrations/fixtures/Test_SetTopicsAsEmptySlice/repository.yml

@@ -0,0 +1,9 @@
+# type Repository struct {
+# 	ID     int64    `xorm:"pk autoincr"`
+# 	Topics []string `xorm:"TEXT JSON"`
+# }
+-
+  id: 1
+-
+  id: 2
+  topics: '["go", "dev"]'

models/repo/TestSearchRepositoryIDsByCondition/repository.yml

@@ -28,3 +28,4 @@
   size: 0
   is_fsck_enabled: true
   close_issues_via_commit_in_any_branch: false
+  topics: '[]'

models/repo/repo.go

@@ -183,7 +183,7 @@ type Repository struct {
 	StatsIndexerStatus              *RepoIndexerStatus `xorm:"-"`
 	IsFsckEnabled                   bool               `xorm:"NOT NULL DEFAULT true"`
 	CloseIssuesViaCommitInAnyBranch bool               `xorm:"NOT NULL DEFAULT false"`
-	Topics                          []string           `xorm:"TEXT JSON"`
+	Topics                          []string           `xorm:"TEXT JSON NOT NULL"`
 	ObjectFormatName                string             `xorm:"VARCHAR(6) NOT NULL DEFAULT 'sha1'"`
 
 	TrustModel TrustModelType
@@ -196,6 +196,13 @@ type Repository struct {
 	ArchivedUnix timeutil.TimeStamp `xorm:"DEFAULT 0"`
 }
 
+// BeforeInsert will be invoked by XORM before updating a record
+func (repo *Repository) BeforeInsert() {
+	if repo.Topics == nil {
+		repo.Topics = []string{}
+	}
+}
+
 func init() {
 	db.RegisterModel(new(Repository))
 }

services/repository/create_test.go

@@ -147,3 +147,13 @@ func TestIncludesAllRepositoriesTeams(t *testing.T) {
 	}
 	require.NoError(t, organization.DeleteOrganization(db.DefaultContext, org), "DeleteOrganization")
 }
+
+func TestCreateRepository(t *testing.T) {
+	require.NoError(t, unittest.PrepareTestDatabase())
+	user := unittest.AssertExistsAndLoadBean(t, &user_model.User{ID: 1})
+
+	r, err := CreateRepositoryDirectly(db.DefaultContext, user, user, CreateRepoOptions{Name: "repo-last"})
+	require.NoError(t, err)
+	require.NotNil(t, r.Topics)
+	require.Empty(t, r.Topics)
+}

tests/e2e/fixtures/repository.yml

@@ -10,3 +10,4 @@
   is_private: true
   status: 0
   lfs_size: 8192
+  topics: '[]'

tests/integration/fixtures/TestAdminDeleteUser/repository.yml

@@ -28,3 +28,4 @@
   size: 0
   is_fsck_enabled: true
   close_issues_via_commit_in_any_branch: false
+  topics: '[]'