internal/database: Transact supports any isolation level

- Add an arg to Transact for the isolation level
- Remove TransactSerializable

This makes it possible to use other levels, and makes it easier to see
which level is being used for each transaction.

Change-Id: Iba5e2920b4139e5e2f0f8c6b331a658d7c84f60f
Reviewed-on: https://team-review.git.corp.google.com/c/golang/discovery/+/758942
CI-Result: Cloud Build <devtools-proctor-result-processor@system.gserviceaccount.com>
Reviewed-by: Julie Qiu <julieqiu@google.com>

1 files changed, 2 insertions, 2 deletions

diff --git a/internal/postgres/versionstate.go b/internal/postgres/versionstate.go
index 22a38e13..f2bfc99d 100644
--- a/internal/postgres/versionstate.go
+++ b/internal/postgres/versionstate.go
@@ -36,7 +36,7 @@ func (db *DB) InsertIndexVersions(ctx context.Context, versions []*internal.Inde
 		DO UPDATE SET
 			index_timestamp=excluded.index_timestamp,
 			next_processed_after=CURRENT_TIMESTAMP`
-	return db.db.Transact(ctx, func(tx *database.DB) error {
+	return db.db.Transact(ctx, sql.LevelDefault, func(tx *database.DB) error {
 		return tx.BulkInsert(ctx, "module_version_states", cols, vals, conflictAction)
 	})
 }
@@ -57,7 +57,7 @@ func (db *DB) UpsertModuleVersionState(ctx context.Context, modulePath, vers, ap
 		numPackages = &n
 	}
 
-	return db.db.Transact(ctx, func(tx *database.DB) error {
+	return db.db.Transact(ctx, sql.LevelDefault, func(tx *database.DB) error {
 		if err := upsertModuleVersionState(ctx, tx, modulePath, vers, appVersion, numPackages, timestamp, status, goModPath, fetchErr); err != nil {
 			return err
 		}