feat: add DbContext factory support (#49)

[dmitrii-kiselev]

Closes #49

[dmitrii-kiselev]

Hi @TanvirArjel,

Please take a look at my pull request when you have some free time.
It will add some critical missing features.

Best Regards,
Dmitrii Kiselev

[TanvirArjel]

@dmitrii-kiselev I am still not sure about why services.AddQueryRepository<YourDbContext1>(); will not work worked in Blazor but services.AddQueryRepositoryFactory<YourDbContext>(); will work. Could you please provide a runnable blazor demo app where services.AddQueryRepository<YourDbContext1>(); is not working and that's why we need to use services.AddQueryRepositoryFactory<YourDbContext>();

Thanks!

[dmitrii-kiselev]

Hi @TanvirArjel,

Thank you for your feedback.
I will prepare a detailed example for you.

For now, I will attach a brief description:
https://learn.microsoft.com/en-us/ef/core/dbcontext-configuration/#using-a-dbcontext-factory-eg-for-blazor

Since the Repository<TDbContext> and QueryRepository<TDbContext> classes are internal, there is currently no way to create multiple parallel repositories with independent DbContext.

EF Core doesn't support multiple parallel operations being run on the same context instance. You should always wait for an operation to complete before beginning the next operation. This is typically done by using the await keyword on each async operation.
https://learn.microsoft.com/en-us/ef/core/miscellaneous/async

We can experiment with dependency injection using a Transient lifetime.
We can use IDbContextFactory<TDbContext>, but the created context instance cannot be integrated into the repository due to implementation scope.
Even by making the Repository<TDbContext> and QueryRepository<TDbContext> classes public, we will have to create our factory to follow the clean architecture, so it is better to implement this in the library.

So the best option is a factory that allows us to create transient instances and destroy them by using statement.

Best Regards,
Dmitrii Kiselev