Properly migrate ban staff ID

cmd/gochan-migration/internal/pre2021/bans.go

@@ -54,6 +54,7 @@ func (m *Pre2021Migrator) migrateBan(tx *sql.Tx, ban *migrationBan, boardID *int
 	migratedBan.ExpiresAt = ban.expires
 	migratedBan.Permanent = ban.permaban
 	migratedBan.Message = ban.reason
+	migratedBan.StaffID = ban.staffID
 	migratedBan.StaffNote = ban.staffNote
 	if err := gcsql.NewIPBanTx(tx, migratedBan); err != nil {
 		errEv.Err(err).Caller().
@@ -109,6 +110,20 @@ func (m *Pre2021Migrator) migrateBansToNewDB() error {
 			}
 		}
 
+		ban.staffID, err = gcsql.GetStaffID(ban.staff)
+		if errors.Is(err, gcsql.ErrUnrecognizedUsername) {
+			// username not found after staff were migrated, use a stand-in account to be updated by the admin later
+			migrationUser, err := m.getMigrationUser(errEv)
+			if err != nil {
+				return err
+			}
+			common.LogWarning().
+				Str("username", ban.staff).
+				Str("migrationUser", migrationUser.Username).
+				Msg("Ban staff not found in migrated staff table, using migration user instead")
+			ban.staffID = migrationUser.ID
+		}
+
 		if ban.ip != "" {
 			if net.ParseIP(ban.ip) == nil {
 				gcutil.LogWarning().

cmd/gochan-migration/internal/pre2021/bans_test.go

@@ -22,6 +22,10 @@ func TestMigrateBansToNewDB(t *testing.T) {
 		t.FailNow()
 	}
 
+	if !assert.NoError(t, migrator.MigrateStaff()) {
+		t.FailNow()
+	}
+
 	if !assert.NoError(t, migrator.MigrateBans()) {
 		t.FailNow()
 	}
@@ -30,6 +34,7 @@ func TestMigrateBansToNewDB(t *testing.T) {
 		t.FailNow()
 	}
 	assert.Equal(t, 6, len(bans), "Expected to have 4 valid bans")
+	assert.NotZero(t, bans[0].StaffID, "Expected ban staff ID field to be set")
 
 	var numInvalidBans int
 	assert.NoError(t, gcsql.QueryRowSQL("SELECT COUNT(*) FROM DBPREFIXip_ban WHERE message = ?", []any{"Full ban on 8.8.0.0/16"}, []any{&numInvalidBans}))