public AmbientContextSuppressor()
{
_savedScope = UnitOfWorkTransactionScope.GetAmbientScope();
// We're hiding the ambient scope but not removing its instance
// altogether. This is to be tolerant to some programming errors.
//
// Suppose we removed the ambient scope instance here. If someone
// was to start a parallel task without suppressing
// the ambient context and then tried to suppress the ambient
// context within the parallel task while the original flow
// of execution was still ongoing (a strange thing to do, I know,
// but I'm sure this is going to happen), we would end up
// removing the ambient context instance of the original flow
// of execution from within the parallel flow of execution!
//
// As a result, any code in the original flow of execution
// that would attempt to access the ambient scope would end up
// with a null value since we removed the instance.
//
// It would be a fairly nasty bug to track down. So don't let
// that happen. Hiding the ambient scope (i.e. clearing the CallContext
// in our execution flow but leaving the ambient scope instance untouched)
// is safe.
UnitOfWorkTransactionScope.HideAmbientScope();
}
public ITDbContext Get <ITDbContext>() where ITDbContext : DbContext
{
var ambientUnitOfWorkScope = UnitOfWorkTransactionScope.GetAmbientScope();
if (ambientUnitOfWorkScope == null)
{
return(default(ITDbContext));
}
else
{
return(ambientUnitOfWorkScope.DbContexts.Get <ITDbContext>());
}
}