Upgrade from 5.5.3 to 7.0 And my constructor injection is no longer working

[tdyocum]

Hello,

After delaying the migration of my apps from CSLA 5.5.3 to CSLA 6+, I decided to take the plunge today with one of my small apps, which is a console app in .net 6.

We've had DI (injecting our services via the constructor) in this console app already, but we were using the static DataPortal in CSLA 5.5.3.

I just migrated the app to CSLA 7 over the past two days. I believe I have everything configured properly as my configured services are initialized and working properly in the console app. For example, the Serilog service is working within the console app when the app is running.

My issue arises when I Fetch my first business object. The parameterless constructor is called (and not the constructor with the injected services). The first line in the Fetch method is a logging statement. At this point the _logger is null.

I am calling AddCsla as part of my configuration of the console app. I'm just wondering if constructor injection is no longer possible in the CSLA 7 (doubtful) or is there something I'm missing.

I've been through the Upgrade To CSLA 6 documentation many times and can't see something obvious that I missed.

Any help would be appreciated. Thanks in advance!

Tim

[tdyocum]

I've shelved my migration in another branch for now. I don't know why the DI isn't working within my business object when I migrated to CSLA 7., but I can access the services (logging, Dals, etc) elsewhere outside of the business objects. It likely has something to do with me missing something obvious that is needed in the configuration for the csla to use DI.

In my app with CSLA 5.5.3, in addition to my other services being wired up in the Builder (IHostBuilder), the CSLA specific stuff I have is:

... services.AddCsla(); new CslaConfiguration() .DataPortal().AutoCloneOnUpdate(false); ... ApplicationContext.DataPortalActivator = new ObjectActivator(services.BuildServiceProvider(), null);

When I moved to CSLA 7, this is what I have:

...
services.AddCsla(o => o
                        .DataPortal(dp => dp
                            .AutoCloneOnUpdate(false)));
...
services.AddSingleton<IDataPortalActivator, ObjectActivator>();
...
services.AddSingleton<IDataPortalActivator>(provider => new ObjectActivator(services.BuildServiceProvider()));
...

ObjectActivator is a custom object that we created that implements IDataPortalActivator.

Not sure if there is something that I did incorrectly here when configuring the CSLA to use DI? Any help / thoughts / guidance would be appreciated.

thanks,

Tim

[rockfordlhotka]

Constructor injection isn't supported for CSLA-derived types. In other words, there's no ctor injection for business classes.

This is largely because those types are mobile and they get serialized/deserialized in various scenarios (n-level undo and the data portal most commonly). I don't know that it is realistic or desirable to require that all potentially injected services are declared on by client and server - that seems like a nightmare for most folks.

Instead, the data portal implements parameter injection at a method level for data portal operation methods.

[rockfordlhotka]

fwiw, you can use the service locator pattern if you really must have access to a service throughout every business object. After ApplicationContext is set (usually via the IUseApplicationContext interface), you can use ApplicationContext to get instances of any service.

Business class base types implement a virtual OnApplicationContextSet method that you can override to be notified when ApplicationContext has become available.

[tdyocum]

Thank you Rocky for the reply, it is very helpful! I'll change from constructor injection to inject what I need via the dataportal methods. I completely missed that in my prior implementations.