feat: allow transactions w/ lower isolation level

CHANGELOG.md

@@ -6,6 +6,12 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+## [2.12.0] - 2022-02-23
+
+# Added
+
+- Allow starting transactions with lower isolation level (the default is SERIALIZABLE) through an optional flag in startTransaction
+
 ## [2.11.0] - 2022-01-14
 
 # Added

build.gradle

@@ -2,7 +2,7 @@ plugins {
     id 'java-library'
 }
 
-version = "2.11.0"
+version = "2.12.0"
 
 repositories {
     mavenCentral()

src/main/java/io/supertokens/pluginInterface/sqlStorage/SQLStorage.java

@@ -23,6 +23,9 @@
 import io.supertokens.pluginInterface.exceptions.StorageTransactionLogicException;
 
 public interface SQLStorage extends Storage {
+    <T> T startTransaction(TransactionLogic<T> logic, TransactionIsolationLevel isolationLevel)
+            throws StorageQueryException, StorageTransactionLogicException;
+
     <T> T startTransaction(TransactionLogic<T> logic) throws StorageQueryException, StorageTransactionLogicException;
 
     void commitTransaction(TransactionConnection con) throws StorageQueryException;
@@ -34,4 +37,8 @@ public interface SQLStorage extends Storage {
     interface TransactionLogic<T> {
         T mainLogicAndCommit(TransactionConnection con) throws StorageQueryException, StorageTransactionLogicException;
     }
+
+    public enum TransactionIsolationLevel {
+        SERIALIZABLE, REPEATABLE_READ, READ_COMMITTED, READ_UNCOMMITTED, NONE
+    }
 }