IRepositoy.InsertOrUpdateAsync throwing concurrency exception - entity-framework

Question

I was creating a content managment system on ABP using entityframework and .net core. I am getting concurrency exccetion when using InsertOrUpdateAsync. I do not have any data in my table.
Please find the Model used to create table.
[Table("CMSContents")]
public class CMSContent:Entity<int>
{
public const int MAXTITLELENGHT = 128;
public const int MAXCONTENTLENGTH = 10000;
[Key]
[DatabaseGenerated(DatabaseGeneratedOption.Identity)]
public override int Id { get; set; }
/// <summary>
/// The title of the content.
/// </summary>
[Required]
[StringLength(MAXTITLELENGHT)]
public virtual string PageName { get; set; }
/// <summary>
/// The Cms Content
/// </summary>
public virtual string PageContent { get; set; }
protected CMSContent()
{
}
public static CMSContent CreateContent(int id,string title ,string contents)
{
var #content = new CMSContent
{
Id = id,
PageName = title,
PageContent = contents
};
return #content;
}
}
}
Below is the Application service used to call the repository.
public async Task<CMSContent> InsertOrUpdateCMSContent(CreateContentInput input)
{
var #content = CMSContent.CreateContent(input.Id,input.PageName, input.PageContent);
return await _contentManager.InsertOrUpdateAsync(#content);
}
Exception while calling this API from Swagger,
Mvc.ExceptionHandling.AbpExceptionFilter - Database operation expected to affect 1 row(s) but actually affected 0 row(s). Data may have been modified or deleted since entities were loaded. See http://go.microsoft.com/fwlink/?LinkId=527962 for information on understanding and handling optimistic concurrency exceptions.
Abp.Domain.Uow.AbpDbConcurrencyException: Database operation expected to affect 1 row(s) but actually affected 0 row(s). Data may have been modified or deleted since entities were loaded. See http://go.microsoft.com/fwlink/?LinkId=527962 for information on understanding and handling optimistic concurrency exceptions. ---> Microsoft.EntityFrameworkCore.DbUpdateConcurrencyException: Database operation expected to affect 1 row(s) but actually affected 0 row(s). Data may have been modified or deleted since entities were loaded. See http://go.microsoft.com/fwlink/?LinkId=527962 for information on understanding and handling optimistic concurrency exceptions.
at Microsoft.EntityFrameworkCore.Update.AffectedCountModificationCommandBatch.ThrowAggregateUpdateConcurrencyException(Int32 commandIndex, Int32 expectedRowsAffected, Int32 rowsAffected)
at Microsoft.EntityFrameworkCore.Update.AffectedCountModificationCommandBatch.ConsumeResultSetWithoutPropagationAsync(Int32 commandIndex, RelationalDataReader reader, CancellationToken cancellationToken)
at Microsoft.EntityFrameworkCore.Update.AffectedCountModificationCommandBatch.ConsumeAsync(RelationalDataReader reader, CancellationToken cancellationToken)
at Microsoft.EntityFrameworkCore.Update.ReaderModificationCommandBatch.ExecuteAsync(IRelationalConnection connection, CancellationToken cancellationToken)
at Microsoft.EntityFrameworkCore.Update.Internal.BatchExecutor.ExecuteAsync(DbContext _, ValueTuple2 parameters, CancellationToken cancellationToken)
at Microsoft.EntityFrameworkCore.SqlServer.Storage.Internal.SqlServerExecutionStrategy.ExecuteAsync[TState,TResult](TState state, Func4 operation, Func4 verifySucceeded, CancellationToken cancellationToken)
at Microsoft.EntityFrameworkCore.ChangeTracking.Internal.StateManager.SaveChangesAsync(IReadOnlyList1 entriesToSave, CancellationToken cancellationToken)
at Microsoft.EntityFrameworkCore.ChangeTracking.Internal.StateManager.SaveChangesAsync(Boolean acceptAllChangesOnSuccess, CancellationToken cancellationToken)
at Microsoft.EntityFrameworkCore.DbContext.SaveChangesAsync(Boolean acceptAllChangesOnSuccess, CancellationToken cancellationToken)
at Abp.EntityFrameworkCore.AbpDbContext.SaveChangesAsync(CancellationToken cancellationToken) in D:\Github\aspnetboilerplate\src\Abp.EntityFrameworkCore\EntityFrameworkCore\AbpDbContext.cs:line 224
--- End of inner exception stack trace ---
at Abp.EntityFrameworkCore.AbpDbContext.SaveChangesAsync(CancellationToken cancellationToken) in D:\Github\aspnetboilerplate\src\Abp.EntityFrameworkCore\EntityFrameworkCore\AbpDbContext.cs:line 230
at Abp.Zero.EntityFrameworkCore.AbpZeroCommonDbContext`3.SaveChangesAsync(CancellationToken cancellationToken) in D:\Github\aspnetboilerplate\src\Abp.ZeroCore.EntityFrameworkCore\Zero\EntityFrameworkCore\AbpZeroCommonDbContext.cs:line 170
at Abp.EntityFrameworkCore.Uow.EfCoreUnitOfWork.SaveChangesInDbContextAsync(DbContext dbContext) in D:\Github\aspnetboilerplate\src\Abp.EntityFrameworkCore\EntityFrameworkCore\Uow\EfCoreUnitOfWork.cs:line 167
at Abp.EntityFrameworkCore.Uow.EfCoreUnitOfWork.SaveChangesAsync() in D:\Github\aspnetboilerplate\src\Abp.EntityFrameworkCore\EntityFrameworkCore\Uow\EfCoreUnitOfWork.cs:line 68
at Abp.EntityFrameworkCore.Uow.EfCoreUnitOfWork.CompleteUowAsync() in D:\Github\aspnetboilerplate\src\Abp.EntityFrameworkCore\EntityFrameworkCore\Uow\EfCoreUnitOfWork.cs:line 83
at Abp.Domain.Uow.UnitOfWorkBase.CompleteAsync() in D:\Github\aspnetboilerplate\src\Abp\Domain\Uow\UnitOfWorkBase.cs:line 273
at Abp.AspNetCore.Mvc.Uow.AbpUowActionFilter.OnActionExecutionAsync(ActionExecutingContext context, ActionExecutionDelegate next) in D:\Github\aspnetboilerplate\src\Abp.AspNetCore\AspNetCore\Mvc\Uow\AbpUowActionFilter.cs:line 51
at Microsoft.AspNetCore.Mvc.Internal.ControllerActionInvoker.InvokeNextActionFilterAsync()
at Microsoft.AspNetCore.Mvc.Internal.ControllerActionInvoker.Rethrow(ActionExecutedContext context)

Answer 1

I have tried the following approach to make it work, posting as an answer since comment wont allow this many characters.
public async Task<CMSContent> InsertOrUpdateCMSContent(CreateContentInput input)
{
var exists = await _contentRepository
.GetAll()
.AnyAsync(e => e.Id == input.Id);
if (!exists)
{
var #content = CMSContent.CreateContent(input.PageName, input.PageContent);
return await _contentRepository.InsertAsync(#content);
}
else
{
var #content = CMSContent.CreateContent(input.Id, input.PageName, input.PageContent);
return await _contentRepository.UpdateAsync(#content);
}
}