I have an asp.net web api where we are starting a transaction using TransactionScope (only for POST,PUT and DELETE but not for GET) in OnActionExecuting of a global action filter and then completing or rolling it back in OnActionExecuted. Recently we decided to make a change so that we can add SqlAzureExecutionStrategy for at least GET calls (since it only works when there is no user-initiated transaction) so that transient failures can be handled for data fetch. I followed the article here and implemented the same thing in our application.below is the code.
Created a new DB configuration class
public class AzureDbConfiguration : DbConfiguration
{
public const string CallContextKey = "SuspendExecutionStrategy";
public AzureDbConfiguration()
{
this.SetExecutionStrategy("System.Data.SqlClient", () => SuspendExecutionStrategy
? (IDbExecutionStrategy)new DefaultExecutionStrategy()
: new SqlAzureExecutionStrategy());
}
public static bool SuspendExecutionStrategy
{
get
{
return (bool?)CallContext.LogicalGetData(CallContextKey) ?? false;
}
set
{
CallContext.LogicalSetData(CallContextKey, value);
}
}
}
Setting suspendExecutionStrategy to true whenever we need to start the transaction.
public override void OnActionExecuting(HttpActionContext actionContext)
{
//checks if it is not a GET call
if (RequiresTransactionInitiation(actionContext))
{
AzureDbConfiguration.SuspendExecutionStrategy = true;
var transactionCompleter = new TransactionCompleter(GetDependencyScope(actionContext));
transactionCompleter.UnitOfWork.StartTransaction(System.Data.IsolationLevel.ReadCommitted);
}
base.OnActionExecuting(actionContext);
}
public override void OnActionExecuted(HttpActionExecutedContext actionExecutedContext)
{
//checks if it is not a GET call
if (RequiresTransactionCompletion(actionExecutedContext))
{
var transactionCompleter = new TransactionCompleter(GetDependencyScope(actionExecutedContext));
if (actionExecutedContext.Exception == null)
{
transactionCompleter.Complete();
AddEventsToResponseHeader(transactionCompleter.MessageTransactions.OfType<IEventTransaction>(), actionExecutedContext.Response);
}
else
{
transactionCompleter.Rollback();
}
//*********** line is added to just test the value of the property .This always return false.**********
var testValue = AzureDbConfiguration.SuspendExecutionStrategy;
}
base.OnActionExecuted(actionExecutedContext);
}
Problem is that the value of SuspendExecutionStrategy is set correctly in OnActionExecuting but moment the code enters the Controller action or OnActionExecuting it is always false.
I did some investigation and realized that the execution context itself changes when we move from the filter to controller action. So if in OnActionExecuting I check Thread.CurrentThread.ExecutionContext.ToStringJson() I see the value of SuspendExecutionStrategy is available but if I check the same in controller action it is not available and the strange part is everything else in the execution context is still available.
Value of Thread.CurrentThread.ExecutionContext.ToStringJson() in OnActionExecuting
{
"LogicalCallContext": {
"E2ETrace.ActivityID": "80000013-0003-fd00-b63f-84710c7967bb",
"ApplicationInsights.OwinExtensions.OperationIdContext": "1c218be6-1fbb-44bf-b994-4db84115b5a3",
"ApplicationInsights.OwinExtensions.OperationParentIdContext": "72d35ac6-a394-4205-8452-a95b36f8857a",
"SuspendExecutionStrategy" : True
})
Value of Thread.CurrentThread.ExecutionContext.ToStringJson() in Controller Action and OnActionExecuted
{
"LogicalCallContext": {
"E2ETrace.ActivityID": "80000013-0003-fd00-b63f-84710c7967bb",
"ApplicationInsights.OwinExtensions.OperationIdContext": "1c218be6-1fbb-44bf-b994-4db84115b5a3",
"ApplicationInsights.OwinExtensions.OperationParentIdContext": "72d35ac6-a394-4205-8452-a95b36f8857a",
})
So my questions is how is that execution context changes from Action filter to controller action and how come all other values in the execution context are still retained.
