--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/Framework/PostgreSQL/PostgreSQLTransaction.cpp	Wed Jul 04 08:16:29 2018 +0200
@@ -0,0 +1,124 @@
+/**
+ * Orthanc - A Lightweight, RESTful DICOM Store
+ * Copyright (C) 2012-2016 Sebastien Jodogne, Medical Physics
+ * Department, University Hospital of Liege, Belgium
+ * Copyright (C) 2017-2018 Osimis S.A., Belgium
+ *
+ * This program is free software: you can redistribute it and/or
+ * modify it under the terms of the GNU Affero General Public License
+ * as published by the Free Software Foundation, either version 3 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Affero General Public License for more details.
+ * 
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ **/
+
+
+#include "PostgreSQLTransaction.h"
+
+#include "PostgreSQLStatement.h"
+
+#include <Core/Logging.h>
+#include <Core/OrthancException.h>
+
+namespace OrthancDatabases
+{
+  PostgreSQLTransaction::PostgreSQLTransaction(PostgreSQLDatabase& database) :
+    database_(database),
+    isOpen_(false),
+    readOnly_(true)
+  {
+    Begin();
+  }
+
+
+  PostgreSQLTransaction::~PostgreSQLTransaction()
+  {
+    if (isOpen_)
+    {
+      LOG(WARNING) << "PostgreSQL: An active PostgreSQL transaction was dismissed";
+
+      try
+      {
+        database_.Execute("ABORT");
+      }
+      catch (Orthanc::OrthancException&)
+      {
+      }
+    }
+  }
+
+
+  void PostgreSQLTransaction::Begin()
+  {
+    if (isOpen_) 
+    {
+      LOG(ERROR) << "PostgreSQL: Beginning a transaction twice!";
+      throw Orthanc::OrthancException(Orthanc::ErrorCode_BadSequenceOfCalls);
+    }
+
+    database_.Execute("BEGIN");
+    database_.Execute("SET TRANSACTION ISOLATION LEVEL SERIALIZABLE");
+    readOnly_ = true;
+    isOpen_ = true;
+  }
+
+
+  void PostgreSQLTransaction::Rollback() 
+  {
+    if (!isOpen_) 
+    {
+      LOG(ERROR) << "PostgreSQL: Attempting to rollback a nonexistent transaction. "
+                 << "Did you remember to call Begin()?";
+      throw Orthanc::OrthancException(Orthanc::ErrorCode_BadSequenceOfCalls);
+    }
+
+    database_.Execute("ABORT");
+    isOpen_ = false;
+  }
+
+
+  void PostgreSQLTransaction::Commit() 
+  {
+    if (!isOpen_) 
+    {
+      LOG(ERROR) << "PostgreSQL: Attempting to roll back a nonexistent transaction. "
+                 << "Did you remember to call Begin()?";
+      throw Orthanc::OrthancException(Orthanc::ErrorCode_BadSequenceOfCalls);
+    }
+
+    database_.Execute("COMMIT");
+    isOpen_ = false;
+  }
+
+
+  IResult* PostgreSQLTransaction::Execute(IPrecompiledStatement& statement,
+                                          const Dictionary& parameters)
+  {
+    std::auto_ptr<IResult> result(dynamic_cast<PostgreSQLStatement&>(statement).Execute(*this, parameters));
+
+    if (!statement.IsReadOnly())
+    {
+      readOnly_ = false;
+    }
+
+  return result.release();
+  }
+
+
+  void PostgreSQLTransaction::ExecuteWithoutResult(IPrecompiledStatement& statement,
+                                                   const Dictionary& parameters)
+  {
+    dynamic_cast<PostgreSQLStatement&>(statement).ExecuteWithoutResult(*this, parameters);
+
+    if (!statement.IsReadOnly())
+    {
+      readOnly_ = false;
+    }
+  }
+}