private async Task <List <UserExerciseSubmission> > TryGetExerciseSubmissions(int count)
{
var notSoLongAgo = DateTime.Now - TimeSpan.FromMinutes(15);
List <UserExerciseSubmission> submissions;
using (var transaction = db.Database.BeginTransaction(IsolationLevel.Serializable))
{
submissions = db.UserExerciseSubmissions
.AsNoTracking()
.Where(s =>
s.Timestamp > notSoLongAgo &&
s.AutomaticChecking.Status == AutomaticExerciseCheckingStatus.Waiting)
.OrderByDescending(s => s.Timestamp)
.Take(count)
.ToList();
foreach (var submission in submissions)
{
submission.AutomaticChecking.Status = AutomaticExerciseCheckingStatus.Running;
}
await SaveAll(submissions.Select(s => s.AutomaticChecking));
transaction.Commit();
db.ObjectContext().AcceptAllChanges();
}
DateTime value;
foreach (var submission in submissions)
{
unhandledSubmissions.TryRemove(submission.Id, out value);
}
return(submissions);
}
// ReSharper disable once MemberCanBePrivate.Global
public IQueryable <UserIdWrapper> GetUsersByNamePrefix(string name)
{
if (string.IsNullOrEmpty(name))
{
return(db.Users.Select(u => new UserIdWrapper(u.Id)));
}
;
var splittedName = name.Split(new[] { ' ', '\t' }, StringSplitOptions.RemoveEmptyEntries);
var nameQuery = string.Join(" & ", splittedName.Select(s => "\"" + s.Trim().Replace("\"", "\\\"") + "*\""));
var nameParameter = new ObjectParameter("name", nameQuery);
return(db.ObjectContext().CreateQuery <UserIdWrapper>($"[{nameof(GetUsersByNamePrefix)}](@name)", nameParameter));
}
private async Task TryUpdate(string userId, Guid slideId, string ltiRequestJson)
{
var ltiRequestModel = FindElement(userId, slideId);
if (ltiRequestModel == null)
{
ltiRequestModel = new LtiSlideRequest
{
UserId = userId,
SlideId = slideId,
Request = ltiRequestJson
};
}
else
{
ltiRequestModel.Request = ltiRequestJson;
}
db.LtiRequests.AddOrUpdate(ltiRequestModel);
await db.ObjectContext().SaveChangesAsync(SaveOptions.DetectChangesBeforeSave);
db.ObjectContext().AcceptAllChanges();
}