public void should_roll_back_uncommitted_transactions_on_restart()
{
_fileSet = new FileSet(
new IDataFile[] { new DataFile(_dataFileInfo1, _pageSize, _startUpLog), new DataFile(_dataFileInfo2, _pageSize, _startUpLog) },
new ILogFile[] { new LogFile(_logFileInfo1, true, _startUpLog), new LogFile(_logFileInfo2, true, _startUpLog) },
_pagePoolFactory,
_startUpLog);
var databaseFactory = SetupMock <IDatabaseFactory>();
var pageStoreFactory = SetupMock <IPageStoreFactory>();
var pageStore = pageStoreFactory.Open(_fileSet);
var database = databaseFactory.Open(pageStore);
var transaction1 = database.BeginTransaction(null);
_fileSet.Write(
transaction1,
new[] {
new PageUpdate
{
SequenceNumber = 0,
PageNumber = 1,
Offset = 20,
Data = new byte[] { 1, 2, 3 }
}
});
database.CommitTransaction(transaction1);
var transaction2 = database.BeginTransaction(null);
_fileSet.Write(
transaction2,
new[] {
new PageUpdate
{
SequenceNumber = 0,
PageNumber = 1,
Offset = 25,
Data = new byte[] { 4, 5, 6 }
}
});
database.CommitTransaction(transaction2);
var transaction3 = database.BeginTransaction(null);
_fileSet.Write(
transaction3,
new[] {
new PageUpdate
{
SequenceNumber = 0,
PageNumber = 1,
Offset = 5,
Data = new byte[] { 7, 8, 9 }
},
new PageUpdate
{
SequenceNumber = 0,
PageNumber = 1,
Offset = 30,
Data = new byte[] { 10, 11, 12 }
}
});
database.CommitTransaction(transaction3);
// Before the transaction is committed the page should be in its original state
using (var originalPage = _pagePool.Get(1))
{
_fileSet.Read(originalPage);
for (var i = 0; i < _pageSize; i++)
{
Assert.AreEqual(0, originalPage.Data[i]);
}
}
// Commit transactions to the log files but do not update the data files
_fileSet.CommitTransaction(transaction1).Wait();
_fileSet.CommitTransaction(transaction2).Wait();
_fileSet.CommitTransaction(transaction3).Wait();
// Shut down and close all the files
_fileSet.Dispose();
// Reopen all of the files
_fileSet = new FileSet(
new IDataFile[] { new DataFile(_dataFileInfo1, _startUpLog), new DataFile(_dataFileInfo2, _startUpLog) },
new ILogFile[] { new LogFile(_logFileInfo1, false, _startUpLog), new LogFile(_logFileInfo2, false, _startUpLog) },
_pagePoolFactory,
_startUpLog);
// Roll back all transactions
ulong[] mustRollBackVersions;
ulong[] canRollForwardVersions;
_fileSet.GetIncompleteTransactions(out mustRollBackVersions, out canRollForwardVersions);
_fileSet.RollBack(mustRollBackVersions);
_fileSet.RollBack(canRollForwardVersions);
// After rolling back the page should be unchanged in the data file
using (var newPage = _pagePool.Get(1))
{
_fileSet.Read(newPage);
for (var i = 0; i < _pageSize; i++)
{
Assert.AreEqual(0, newPage.Data[i]);
}
}
// There should be no incomplete transactions now
_fileSet.GetIncompleteTransactions(out mustRollBackVersions, out canRollForwardVersions);
Assert.AreEqual(0, mustRollBackVersions.Length);
Assert.AreEqual(0, canRollForwardVersions.Length);
}
