Where to put Audit.Core.Configuration.Setup()

Where can/should this get called? I could not find in the readme the location to call Audit.Core.Configuration.Setup().

I first tried calling Audit.Core.Configuration.Setup() in the database context OnModelCreating(), and the audit table was created. However, there were some null errors when trying to save to the audit table.

Second, I tried tried calling Audit.Core.Configuration.Setup() in the database context OnConfiguring(), since I saw it in another issue. That resulted in the audit table being deleted, so that doesn’t seem like the right place.

Your configuration call to Audit.Core.Configuration.Setup() should be done only once, at the startup of your application.

_Originally posted by @thepirat000 in https://github.com/thepirat000/Audit.NET/issues/247#issuecomment-539686730_

[mrlife]

Thank you, I fixed by adding an explicit key property to the Audit_* model classes so that the Id matched up with the audited model and EF Core uses the explicit key property for its tracking purposes.

e.g.

public class MyModel
{
    public int Id { get; set; }
    public string Property { get; set; }
}
 
public class Audit_MyModel : IAudit
{
    [Key]
    public int AuditId { get; set; }
    public int Id { get; set; }
    public string Property { get; set; }
 
    public string AuditAction { get; set; }
    public DateTime AuditDate { get; set; }
}

I think your library is wonderful and appreciate your work to create and maintain it.

[thepirat000]

I don’t know what the users of the library usually do. There are many data providers for the audit output saving, and there are many use cases for the EntityFramework data provider.

For the DI part, you should be able to access any of your registered services, or the IServiceProvider as a parameter on your Startup.Configure() method and then use it on the setup delegate, for example:

public void Configure(IApplicationBuilder app, IServiceProvider svcProvider)
{
    Audit.Core.Configuration.Setup()
        .UseEntityFramework(ef => ef
            .AuditTypeExplicitMapper(m => m
                .Map<Order, Audit_Order>()
                .Map<OrderItem, Audit_OrderItem>()
                .AuditEntityAction<IAudit>((evt, entry, auditEntity) =>
                {
                    var svc = svcProvider.GetRequiredService<IYourService>();
                    // ...
                })
            )
        );
    // ...
}

or if it’s a singleton, you could just:

public void Configure(IApplicationBuilder app, IYourService svc)
{
    Audit.Core.Configuration.Setup()
        .UseEntityFramework(ef => ef
            .AuditTypeExplicitMapper(m => m
                .Map<Order, Audit_Order>()
                .Map<OrderItem, Audit_OrderItem>()
                .AuditEntityAction<IAudit>((evt, entry, auditEntity) =>
                {
                    // use svc here
                })
            )
        );
    // ...
}

Is the DbSet you need to access on the same DbContext that is being audited? If so, you can access it with GetDbContext() method on the EF event:

using Audit.EntityFramework;
//...
Audit.Core.Configuration.Setup()
      .UseEntityFramework(ef => ef
          .AuditTypeExplicitMapper(m => m
              .Map<Order, Audit_Order>()
              .Map<OrderItem, Audit_OrderItem>()
              .AuditEntityAction<IAudit>((evt, entry, auditEntity) =>
              {
                  var svc = svcProvider.GetRequiredService<IYourService>();
                  var dbContext = evt.GetEntityFrameworkEvent().GetDbContext();
                  // ...
              })
          )
      );