private CriticalSectionState GetCriticalSectionState(int taskDefinitionId, CriticalSectionType criticalSectionType, SqlCommand command)
{
command.Parameters.Clear();
if (criticalSectionType == CriticalSectionType.User)
{
command.CommandText = TokensQueryBuilder.GetUserCriticalSectionStateQuery;
}
else
{
command.CommandText = TokensQueryBuilder.GetClientCriticalSectionStateQuery;
}
command.Parameters.Add("@TaskDefinitionId", SqlDbType.Int).Value = taskDefinitionId;
using (var reader = command.ExecuteReader())
{
var readSuccess = reader.Read();
if (readSuccess)
{
var csState = new CriticalSectionState();
csState.IsGranted = int.Parse(reader[GetCsStatusColumnName(criticalSectionType)].ToString()) == 0;
csState.GrantedToExecution = reader[GetGrantedToColumnName(criticalSectionType)].ToString();
csState.SetQueue(reader[GetQueueColumnName(criticalSectionType)].ToString());
csState.StartTrackingModifications();
return(csState);
}
}
throw new CriticalSectionException("No Task exists with id " + taskDefinitionId);
}
public StartCriticalSectionRequest(TaskId taskId,
string taskExecutionId,
TaskDeathMode taskDeathMode,
CriticalSectionType criticalSectionType)
: base(taskId, taskExecutionId)
{
TaskDeathMode = taskDeathMode;
Type = criticalSectionType;
}
private string GetQueueColumnName(CriticalSectionType criticalSectionType)
{
if (criticalSectionType == CriticalSectionType.User)
{
return("UserCsQueue");
}
return("ClientCsQueue");
}
private string GetCsStatusColumnName(CriticalSectionType criticalSectionType)
{
if (criticalSectionType == CriticalSectionType.User)
{
return("UserCsStatus");
}
return("ClientCsStatus");
}
private string GetGrantedToColumnName(CriticalSectionType criticalSectionType)
{
if (criticalSectionType == CriticalSectionType.User)
{
return("UserCsTaskExecutionId");
}
return("ClientCsTaskExecutionId");
}
public StartCriticalSectionRequest(TaskId taskId,
string taskExecutionId,
TaskDeathMode taskDeathMode,
CriticalSectionType criticalSectionType)
: base(taskId, taskExecutionId)
{
TaskDeathMode = taskDeathMode;
Type = criticalSectionType;
}
public CriticalSectionContext(ICriticalSectionRepository criticalSectionRepository,
TaskExecutionInstance taskExecutionInstance,
TaskExecutionOptions taskExecutionOptions,
CriticalSectionType criticalSectionType)
{
_criticalSectionRepository = criticalSectionRepository;
_taskExecutionInstance = taskExecutionInstance;
_taskExecutionOptions = taskExecutionOptions;
_criticalSectionType = criticalSectionType;
ValidateOptions();
}
public CriticalSectionContext(ICriticalSectionRepository criticalSectionRepository,
TaskExecutionInstance taskExecutionInstance,
TaskExecutionOptions taskExecutionOptions,
CriticalSectionType criticalSectionType)
{
_criticalSectionRepository = criticalSectionRepository;
_taskExecutionInstance = taskExecutionInstance;
_taskExecutionOptions = taskExecutionOptions;
_criticalSectionType = criticalSectionType;
ValidateOptions();
}
private CompleteCriticalSectionResponse ReturnCriticalSectionToken(TaskId taskId, int taskDefinitionId, string taskExecutionId, CriticalSectionType criticalSectionType)
{
var response = new CompleteCriticalSectionResponse();
using (var connection = CreateNewConnection(taskId))
{
SqlTransaction transaction = connection.BeginTransaction(IsolationLevel.Serializable);
var command = connection.CreateCommand();
command.Transaction = transaction;
if (criticalSectionType == CriticalSectionType.User)
command.CommandText = TokensQueryBuilder.ReturnUserCriticalSectionTokenQuery;
else
command.CommandText = TokensQueryBuilder.ReturnClientCriticalSectionTokenQuery;
command.CommandTimeout = ConnectionStore.Instance.GetConnection(taskId).QueryTimeoutSeconds;
command.Parameters.Add("@TaskDefinitionId", SqlDbType.Int).Value = taskDefinitionId;
command.Parameters.Add("@TaskExecutionId", SqlDbType.Int).Value = int.Parse(taskExecutionId);
try
{
command.ExecuteNonQuery();
transaction.Commit();
}
catch (SqlException sqlEx)
{
TryRollBack(transaction, sqlEx);
}
catch (Exception ex)
{
TryRollback(transaction, ex);
}
}
return response;
}
private async Task <CompleteCriticalSectionResponse> ReturnCriticalSectionTokenAsync(TaskId taskId, int taskDefinitionId, string taskExecutionId, CriticalSectionType criticalSectionType)
{
var response = new CompleteCriticalSectionResponse();
using (var connection = await CreateNewConnectionAsync(taskId).ConfigureAwait(false))
{
SqlTransaction transaction = connection.BeginTransaction(IsolationLevel.Serializable);
var command = connection.CreateCommand();
command.Transaction = transaction;
if (criticalSectionType == CriticalSectionType.User)
{
command.CommandText = TokensQueryBuilder.ReturnUserCriticalSectionTokenQuery;
}
else
{
command.CommandText = TokensQueryBuilder.ReturnClientCriticalSectionTokenQuery;
}
command.CommandTimeout = ConnectionStore.Instance.GetConnection(taskId).QueryTimeoutSeconds;
command.Parameters.Add("@TaskDefinitionId", SqlDbType.Int).Value = taskDefinitionId;
command.Parameters.Add("@TaskExecutionId", SqlDbType.Int).Value = int.Parse(taskExecutionId);
try
{
await command.ExecuteNonQueryAsync().ConfigureAwait(false);
transaction.Commit();
}
catch (SqlException sqlEx)
{
TryRollBack(transaction, sqlEx);
}
catch (Exception ex)
{
TryRollback(transaction, ex);
}
}
return(response);
}
private async Task UpdateCriticalSectionStateAsync(int taskDefinitionId, CriticalSectionState csState, CriticalSectionType criticalSectionType, SqlCommand command)
{
command.Parameters.Clear();
if (criticalSectionType == CriticalSectionType.User)
{
command.CommandText = TokensQueryBuilder.SetUserCriticalSectionStateQuery;
}
else
{
command.CommandText = TokensQueryBuilder.SetClientCriticalSectionStateQuery;
}
command.Parameters.Add("@TaskDefinitionId", SqlDbType.Int).Value = taskDefinitionId;
command.Parameters.Add("@CsStatus", SqlDbType.Int).Value = csState.IsGranted ? 1 : 0;
command.Parameters.Add("@CsTaskExecutionId", SqlDbType.Int).Value = csState.GrantedToExecution;
command.Parameters.Add("@CsQueue", SqlDbType.VarChar, 8000).Value = csState.GetQueueString();
await command.ExecuteNonQueryAsync().ConfigureAwait(false);
}
private string GetCsStatusColumnName(CriticalSectionType criticalSectionType)
{
if (criticalSectionType == CriticalSectionType.User)
return "UserCsStatus";
return "ClientCsStatus";
}
private CriticalSectionState GetCriticalSectionState(int taskDefinitionId, CriticalSectionType criticalSectionType, SqlCommand command)
{
command.Parameters.Clear();
if (criticalSectionType == CriticalSectionType.User)
command.CommandText = TokensQueryBuilder.GetUserCriticalSectionStateQuery;
else
command.CommandText = TokensQueryBuilder.GetClientCriticalSectionStateQuery;
command.Parameters.Add("@TaskDefinitionId", SqlDbType.Int).Value = taskDefinitionId;
using (var reader = command.ExecuteReader())
{
var readSuccess = reader.Read();
if (readSuccess)
{
var csState = new CriticalSectionState();
csState.IsGranted = int.Parse(reader[GetCsStatusColumnName(criticalSectionType)].ToString()) == 0;
csState.GrantedToExecution = reader[GetGrantedToColumnName(criticalSectionType)].ToString();
csState.SetQueue(reader[GetQueueColumnName(criticalSectionType)].ToString());
csState.StartTrackingModifications();
return csState;
}
}
throw new CriticalSectionException("No Task exists with id " + taskDefinitionId);
}
public CompleteCriticalSectionRequest(TaskId taskId, string taskExecutionId, CriticalSectionType criticalSectionType)
: base(taskId, taskExecutionId)
{
Type = criticalSectionType;
}
private bool TryAcquireCriticalSection(TaskId taskId, int taskDefinitionId, string taskExecutionId, CriticalSectionType criticalSectionType)
{
bool granted = false;
using (var connection = CreateNewConnection(taskId))
{
SqlTransaction transaction = connection.BeginTransaction(IsolationLevel.Serializable);
var command = connection.CreateCommand();
command.Transaction = transaction;
command.CommandTimeout = ConnectionStore.Instance.GetConnection(taskId).QueryTimeoutSeconds; ;
try
{
AcquireRowLock(taskDefinitionId, taskExecutionId, command);
var csState = GetCriticalSectionState(taskDefinitionId, criticalSectionType, command);
CleanseOfExpiredExecutions(csState, command);
if (csState.IsGranted)
{
// if the critical section is still granted to another execution after cleansing
// then we rejected the request. If the execution is not in the queue then we add it
if (!csState.ExistsInQueue(taskExecutionId))
csState.AddToQueue(taskExecutionId);
granted = false;
}
else
{
if (csState.GetQueue().Any())
{
if (csState.GetFirstExecutionIdInQueue() == taskExecutionId)
{
GrantCriticalSection(csState, taskDefinitionId, taskExecutionId, command);
csState.RemoveFirstInQueue();
granted = true;
}
else
{
// not next in queue so cannot be granted the critical section
granted = false;
}
}
else
{
GrantCriticalSection(csState, taskDefinitionId, taskExecutionId, command);
granted = true;
}
}
if (csState.HasBeenModified)
UpdateCriticalSectionState(taskDefinitionId, csState, criticalSectionType, command);
transaction.Commit();
}
catch (SqlException sqlEx)
{
TryRollBack(transaction, sqlEx);
}
catch (Exception ex)
{
TryRollback(transaction, ex);
}
}
return granted;
}
private string GetQueueColumnName(CriticalSectionType criticalSectionType)
{
if (criticalSectionType == CriticalSectionType.User)
return "UserCsQueue";
return "ClientCsQueue";
}
private string GetGrantedToColumnName(CriticalSectionType criticalSectionType)
{
if (criticalSectionType == CriticalSectionType.User)
return "UserCsTaskExecutionId";
return "ClientCsTaskExecutionId";
}
public CompleteCriticalSectionRequest(TaskId taskId, string taskExecutionId, CriticalSectionType criticalSectionType)
: base(taskId, taskExecutionId)
{
Type = criticalSectionType;
}
private async Task <bool> TryAcquireCriticalSectionAsync(TaskId taskId, int taskDefinitionId, string taskExecutionId, CriticalSectionType criticalSectionType)
{
bool granted = false;
using (var connection = await CreateNewConnectionAsync(taskId).ConfigureAwait(false))
{
SqlTransaction transaction = connection.BeginTransaction(IsolationLevel.Serializable);
var command = connection.CreateCommand();
command.Transaction = transaction;
command.CommandTimeout = ConnectionStore.Instance.GetConnection(taskId).QueryTimeoutSeconds;;
try
{
await AcquireRowLockAsync(taskDefinitionId, taskExecutionId, command).ConfigureAwait(false);
var csState = await GetCriticalSectionStateAsync(taskDefinitionId, criticalSectionType, command).ConfigureAwait(false);
await CleanseOfExpiredExecutionsAsync(csState, command).ConfigureAwait(false);
if (csState.IsGranted)
{
// if the critical section is still granted to another execution after cleansing
// then we rejected the request. If the execution is not in the queue then we add it
if (!csState.ExistsInQueue(taskExecutionId))
{
csState.AddToQueue(taskExecutionId);
}
granted = false;
}
else
{
if (csState.GetQueue().Any())
{
if (csState.GetFirstExecutionIdInQueue() == taskExecutionId)
{
GrantCriticalSection(csState, taskDefinitionId, taskExecutionId, command);
csState.RemoveFirstInQueue();
granted = true;
}
else
{
// not next in queue so cannot be granted the critical section
granted = false;
}
}
else
{
GrantCriticalSection(csState, taskDefinitionId, taskExecutionId, command);
granted = true;
}
}
if (csState.HasBeenModified)
{
await UpdateCriticalSectionStateAsync(taskDefinitionId, csState, criticalSectionType, command).ConfigureAwait(false);
}
transaction.Commit();
}
catch (SqlException sqlEx)
{
TryRollBack(transaction, sqlEx);
}
catch (Exception ex)
{
TryRollback(transaction, ex);
}
}
return(granted);
}
private void UpdateCriticalSectionState(int taskDefinitionId, CriticalSectionState csState, CriticalSectionType criticalSectionType, SqlCommand command)
{
command.Parameters.Clear();
if (criticalSectionType == CriticalSectionType.User)
command.CommandText = TokensQueryBuilder.SetUserCriticalSectionStateQuery;
else
command.CommandText = TokensQueryBuilder.SetClientCriticalSectionStateQuery;
command.Parameters.Add("@TaskDefinitionId", SqlDbType.Int).Value = taskDefinitionId;
command.Parameters.Add("@CsStatus", SqlDbType.Int).Value = csState.IsGranted ? 1 : 0;
command.Parameters.Add("@CsTaskExecutionId", SqlDbType.Int).Value = csState.GrantedToExecution;
command.Parameters.Add("@CsQueue", SqlDbType.VarChar, 8000).Value = csState.GetQueueString();
command.ExecuteNonQuery();
}
