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  1. As promised, you have delivered again Mukesh. Still not completely clear about what goes where but your article has greatly improved my understanding about this architecture. I also liked that you started with a clean slate as most out there just show it ready-made and try to explain from there. I am leaning towards the API template as I usually use SPA’s. Overall, awesome stuff.

    1. Hi Victor, Thanks for the early feedback. Yes, this is quite a lot of details that may be overwhelming initially. I have tried to make it as simple as possible to understand how the entire architecture is designed. But I guess there is a lot of room for optimizing the content. I Will work on that as well. However, you could also check the code on my GitHub to get a detailed understanding.

      Thanks and Regards

      1. This post is very clear and easy to understand.
        And I am accidently know your website from the Asp.Net Core on Facebook several months ago and still follow you until now.
        You has helped me a lots to improve my Asp.Net skills! I have read a lot of websites on the internet but almost these a articles are not clearly or hard to understand because they don’t write everything from scrath like you did!

        Keep posting!

        Thanks you so much Mukesh!

    2. Like with many online examples, your example is missing real life examples. It would been even better when you implement validation rules, authentication/authorization, etc.

      This way developers can really learn how the onion architecture is implemented.

      Anyway thanks for effort, really appreciated.

      1. YES! What Rob says. There are so many unanswered questions and pitfalls once you start coding. For beginners it would be extremely beneficial to have real world examples

    3. What a pleasure to follow an article with code that works straight away. Now I want to read your other articles as well!

  2. services.AddPersistence(Configuration);
    not working for me, do I need to add project reference to webapi?
    If yes, then whats the point of abstraction.

    1. yes started with very good notion but ending up few things which is not really great and can be modified in next version of this boilerplate code

      * Avoid direct reference of DAL/Persistence layer to Presentation layer
      * can introduce AggregateRoot etc
      * we can also avoid having reference of EF in application and Presentation layer

      Well the notion is Data access layer technology keep changing after almost 3-4 years of life span.
      So if tomorrow we want to change EF with any other ORM(like dapper etc) it will impact Persistence, Application and Presentation layer. which is NOT good.

      since we are ending up with CQRS then we may think of adding event-sourcing etc, however event sourcing or event storing is NOT compulsion to to implement CQRS

  3. Thanks Mukesh for your effort in this great article but when will you write about these topics ‘Authentication, Exception Handling, Mediator Pipeline Logging, Error Logging, Background Processing, Response Wrappers’

    1. Hi, Thanks for writing.

      Authentication, Response Wrappers, Error Logging and Job Processing is already covered in my other articles.
      Here are the links –
      https://codewithmukesh.com/blog/aspnet-core-api-with-jwt-authentication/ (Auth)
      https://codewithmukesh.com/blog/hangfire-in-aspnet-core-3-1/ (job processing)
      https://codewithmukesh.com/blog/serilog-in-aspnet-core-3-1/ (error logging)
      https://codewithmukesh.com/blog/pagination-in-aspnet-core-webapi/ (wrappers & paginations)

      I forgot to add the links to this articles. Thanks for reminding me 😀

      Regards.

  4. Firstly, Add Reference to the “Domain” Project.

    Then, install the required packages via Console.

    Install-Package MediatR.Extensions.Microsoft.DependencyInjection
    Install-Package Microsoft.EntityFrameworkCore
    —————————————————————————————————-

    I think it should be in Application Project, shouldn’t it?

  5. I’ve been building an application with similar architecture. There should be no reference from Presentation layer to the Infrastructure layer, where the ApplicationDbContext is. But I have not been able to achieve this in practice. You run database migrations directly with command update-database from Package Manager Console. But what about in production? I want to have automatic migrations there when I deploy new version. Natural place would be to run migrations in Startup class (which is in Presentation layer because it’s application root). I’ve registered my dependency in Infrastrucure layer as you by using IApplicationDbContext interface (I use Autofac modules but same idea), but when I execute the Migrate method in startup, I get following error:

    Unable to create an object of type ‘ApplicationDbContext’. Add an implementation of ‘IDesignTimeDbContextFactory’ to the project, or see https://go.microsoft.com/fwlink/?linkid=851728 for additional patterns supported at design time.

    The only way around seems that I need to implement IDesignTimeDbContextFactory interface in Presentation layer, and then I’m forced to have reference to Infrastrucure layer, like this: https://codingblast.com/entityframework-core-idesigntimedbcontextfactory/

    Any advice? How you handle migrations in production?

    1. Given the fact that ASP.NET Core has DI and Services, it would not make sense to not have a reference between these layers.
      Running migrations / seeding at startup might be a bit of performance bottleneck. You could use the CLI for this. Sometimes we use SQL scripts as well when required. (There is something called Script migrations in EFCore).

      Thanks and Regards

    2. Database migration should be handled by your CI/CD pipeline. Your application code shouldn’t know nor care about such thing as the database schema version.
      This is a infrastructure concern and should be handled by the application infrastructure. It can be a separate repo that creates external resources (a database is the simplest example) or a tool that lives in the application’s repo but runs before the application itself.
      This way you achieve one of the most important principles: the separation of the application and infrastructure layers. Which allows while coexist also be developed by separate people and at separate pace.

  6. Thanks for the article.

    Even though you said application layer doesn’t depend on any other layers, you immediately leak entity Framework and asp.net core into it by the means of dbset and iservicecollection. This is effectively the same as leaking infrastructure and presentation layer into application layer, you’re bound to the technologies and cannot replace them with anything else.

    1. Hi, Thanks for writing.

      Yes, EFCore is installed in the Application layer as well. This approach is under the assumption that we would not switch away from EFCore for a very long time, which I think would not happen for at least the next 10-15 years. Also, Application layer is not depending on anything else other than the domain entities.

      1. Application is the composition root so must know (references) all underlying libraries and explicit dependencies. You may have some implicit but then the app/cr have no knowledge of them.
        You can move the composition logic in a separate project but in most cases it makes no difference, nor sense.
        Adding a layer of abstraction for ORM or cloud provider are the best example of faux abstraction, the one that add no good but unnecessarily complicates the codebase. it’s also known as the overengineering. There are special cases when you need (a library to do exactly that) but again in most cases it makes no sense.

  7. You may want to sort usings in a way that System will go on top. You can configure VS accordingly.

    Also validation clutters the code of controllers, should be moved to a separate class (because of OOP+SRP which are the foundational principles behind CQRS).

  8. Hi, Thanks for the article and you are doing great effort, please keep it up.

    In Persistence layer SaveChanges() should not be override method?

      1. Hi Mukesh, thank you for this great article.

        I am reading this on an Ipad pro (1024×1366) and there is a horizontal scrollbar that is a bit annoying when I scroll vertically.

        Issue seems like the deeply nested comments.

        Hope you can take a look at it.

  9. I had been working on a similar .NET Core onion architecture example for my team as well, so I’ve forwarded this article to them while I finish up my own example. I anticipate the setup walkthrough being more helpful than my sequence of PRs they would be viewing. Thanks for the writeup!

    I forwarded the article with the following caveats though…
    – Anemic domain models are an anti-pattern (https://martinfowler.com/bliki/AnemicDomainModel.html). The Product class, being part of the Domain project, falls squarely in this category. Primitive obsession is also a problem (see https://blog.ploeh.dk/2011/05/25/DesignSmellPrimitiveObsession/). The Product class is being used for both in-memory processing and for persistence, a clear violation of the single responsibility principle. Pluralsight has a great course on moving off the anti-pattern: https://www.pluralsight.com/courses/refactoring-anemic-domain-model
    – As someone else already mentioned, the IApplicationDbContext interface couples consuming components to the use of EF Core (because DbSet is a public property field). Introducing DDD repositories that hide EF Core entirely would be preferred. https://docs.microsoft.com/en-us/dotnet/architecture/microservices/microservice-ddd-cqrs-patterns/infrastructure-persistence-layer-design has more details.
    – Since MediatR is already being used to encapsulate system commands, one could instead implement the “unit of work” pattern as a generic pipeline behavior rather than requiring developers to inject IApplicationDbContext and call SaveChanges explicitly for every request handler. https://github.com/kgrzybek/modular-monolith-with-ddd#36-cross-cutting-concerns has some relevant details (in addition to being a high-quality comprehensive .NET Core onion/CQRS/DDD example).

    Again, I appreciate the writeup! It just has a few less-than-ideal architecture choices (for long-lived solutions) that prevent me from recommending it as-is. I’m happy to answer any questions.

    1. Hi. Thanks for the feedback. Firstly, this is just a basic level implementation for the beginners. Did not want it to be much complex.
      1. Yes, Automapper and DTO classes will be used.
      2. Isnt Repositories a bad idea to go along with EFCore? and more redundant code?

      Thanks for sharing, and I am currently working on a full fledged Clean Architecture for WebApi.

      Regards

        1. Given the fact that EFCORE is already built on Repository pattern and UOW, do you really need another layer of abstraction layer over it using a IREPO? I really don’t see any advantage of such an approach here. Also, as the application scales up, doesn’t your repo count grow too unnecessarily? Please correct me if I am wrong

          1. The answer is, as always, “it depends”, but I would argue the extra abstraction layer is definitely worth the effort for projects of sufficient size and scope.

            As currently written, your request handler implementations depend on **the entire database**. That is what IApplicationDbContext is; presumably, you will be exposing all tables with this object. For a simple project, this may be fine. However, as your project increases in size and scope, that particular architecture choice will enable database-level entanglements that make it incredibly difficult to refactor and decompose the solution (into modules and/or microservices) down the road. I recommend the book Monolith to Microservices by Sam Newman for some insights on this topic.

            “The entire database” is not an abstraction. It’s too low-level. Interestingly, per your own admission, “EFCORE is already built on Repository pattern and UOW” and so why have IApplicationDbContext at all if all it does is expose EFCore classes (DbSet) and functions? YAGNI.

            Implementing your own repositories (one per aggregate root) as an abstraction layer over top of EF Core has multiple benefits:
            – your domain layer can define the repository interface, while the implementation of the repository goes in the infrastructure layer; this is onion architecture in action! (depend on abstractions, not implementations)
            – per DDD, request handlers are analogous to system commands, and system commands are part of your domain layer; your current implementation violates DDD onion architecture because your request handlers depend directly on EFCore (via IApplicationDbContext)
            – repositories expose the precise, limited set of database operations required to service your domain; this makes your code **simpler** because you have defined your own API over the raw database and your request handlers will use this API
            – per the previous point, database-related complexity is confined to the repositories: the repository takes care of loading and mapping everything needed to construct the aggregate root in memory; with your current implementation, this complexity will go in your request handlers, which should be concerned with domain logic only
            – per the previous two points, repositories are useful and reusable (they bundle reusable pieces of database functionality)

            Elsewhere you had mentioned that adding repositories increases lines of code and yes, it does; however, “number of lines of code” is useless as a quality metric. Coupling between components and between layers is a much better quality heuristic, and onion architecture is all about managing that coupling.

          2. Great. This actually cleared a lot of Architecture doubts for me. Thanks! So, in the implementation of the Repository, is it better to use the concrete class ApplicationDbContext? or go with IApplicationDbContext? So with this approach, we no longer are bound to just EFCore. Else, is there any major issue that you see with this implementation. PS, apart from the usage of Automapper / DTO Classes

            Thanks and Regards

          3. It is fine for the repository implementations to be directly coupled to EFCore (i.e. use ApplicationDbContext directly). While the repository **abstraction** is part of your domain layer, the **implementation** of the repository abstraction is an infrastructure concern and resides on the outermost layer of the onion. Your application’s composition root (which has knowledge of all components used in your system) is responsible for associating that repository abstraction with its implementation. Your request handlers will not know about the implementation of the repository at all (provided your repository abstraction does not leak implementation details).

            You can find an example of this at https://github.com/kgrzybek/modular-monolith-with-ddd/blob/master/src/Modules/Meetings/Domain/Meetings/IMeetingGroupRepository.cs (abstraction in domain layer) and https://github.com/kgrzybek/modular-monolith-with-ddd/blob/master/src/Modules/Meetings/Infrastructure/Domain/Meetings/MeetingRepository.cs (implementation in infrastructure layer). I highly encourage you to check out that GitHub repo for more high-quality examples of DDD onion architecture in action. It certainly upped my game!

  10. There is no essential difference between n-tier, onion, hexagonal, layered etc architectures. If you were to cut from the outside to the centre of your onion diagram, then bend the edges upwards, you’d have the same diagram as for n-tier, for example.
    You mention that n-tier layers are tightly coupled, but that is not actually a requirement! They may be, but that’s just poor design. It remains poor design no matter which architecture you think you’re using. It is equally possible to do “onion architecture” badly and tightly couple everything.
    These days we have a different idea of what should go in a layer than 30 years ago, and we are more careful about where we put domain logic, presentation logic, and so on. But the architectural principles are all essentially the same.
    Layers should not depend too tightly on each other (and should only have any dependency one way, and one layer deep). But that always applies.
    The details always matter here. All these architectures are basically saying you should split up your code into separate areas of concern, and all the normal rules about dependencies and coupling always apply, redardless. If you put your code in the wrong layer, or couple things that shouldn’t be coupled, or whatever, none of the architectures will be successful.
    Moreover, I think you have made several mistakes in your example.
    Using solution folders in Visual Studio is bad. They are are horrible mistake made by Microsoft, and should never be used.
    Using different projects for different layers is only ever coincidentally a good idea. You’d have to have a very large project before doing that made any sense, in which case moving the application into a more service-based architecture might well be a better choice.
    You should use different projects when you need different deliverables. Layers do not necessarily need to be in different projects, especially in small applications.
    And it is still extremely disappointing that people refuse to work in a test-driven way, and examples like this ignore testing altogether.

  11. Hi Mukesh,

    This is a very nice introductory article to some important concepts, and you deserve props for contributing to the community.

    However, I wanted to correct a terminology issue. It’s relatively minor, but could lead to confusion for some people down the road.

    You are using CQS (Command Query Seperation), not CQRS (Command Query Responsibility Segregation).

    Command Query Seperation splits commands and queries into different request types, where commands alter state and may introduce side effects, while queries are read-only and side-effect free. The two types of requests can/do share a common model and data store. This is an application level pattern to clarify intent.

    Command Query Responsibility Segregation is the use of two completely separate models, and often different data stores, where the query store is generally optimized for read efficiency, while the command store is optimized for processing changes. For instance, your Commands may use a service bus or Event Sourcing to send changes on for further processing, while your Queries may use compiled SQL views for querying.

    CQS also tends to imply immediate consistency between the read and write models, while CQRS often implies eventual consistency between the read and write models.

    Anyway, I suspect you know much or all of this, but I thought it worth addressing so nobody gets confused.

    Thanks again

  12. Hi. Nice and clean article. I have one question though: are you using the IDbContext for a specific reason? Do you prefer this instead of the Repository pattern? Normally I use repositories because I can work without any EF reference in my domain / application layer but having a DbContext can be handy when using things like .Include(). Just wondering 🙂

    1. Thanks for your feedback!
      This is quite a debated question over at the community. This is how I look at it. EFCore is a well-matured variant of EF. EFCore implements Repository Pattern and UOW already, as stated by Microsoft. In most of the cases, I fail to see the advantage of having another repository layer over it. Get it? Why have another abstraction of Repository, when it is already done within EFCore? Also, with this approach, doesn’t the Lines of code increase? I may be wrong but haven’t come across a use-case where I really need a repo class. What do you think about this?

      1. Good point. Maybe I try to hard not to get any implementation details in the Application/Domain layer. It makes it harder in some cases. I have swapped EF Core for Dapper (but only once) which was fairly easy because of the repos though. Gonna think about it, thanks!

  13. Hi ,

    Thanks for the perfect explanation. I just’ve a question , In case of integrating with other component , let’s say twilio service , so in this case I should Add the interfaces with the desired twilio functionality i want to use, in the application layer then create new project under infrastructure folder ex: XYZ.Infrastructure.Twilio then add the implementation there , correct me if I’m wrong 🙂

    1. Hi, Thanks for the Feedback.
      Yes. It actually depends on the use case as well.
      1. You could either merge services like Twilio into a single Project layer and implement the interface within each corresponding folder. eg. Infrastruction.Communication / Twilio. This is if you think the infrastructure implementation is not very complex.
      2. In other cases, like you have mentioned, go with Infrastructure.Twilio. This is if you want a really good separation of the implementations, as each Project will be generating a DLL.

      Thanks and Regards.

  14. While this architecture is clean enough and as Mukesh said , EFCore already implements Repository Pattern , but still there is some cases you can introduce new Repository layer ,
    1- If you want to hide the implementation of your ORM ( EF ) and you have some assumtions that you would change your ORM later ( which is not the case most of the time)

    2-if you want to limit access to some of your entities you can Introduce a new empty inteface called IAggregateroot then make your IRepository inherit from IAggregateRoot then set your entites which is accessable every where to implement IAggregateRoot except the one you don’t want anyone to access it directlty so in this case when you try to inject IRepository where T : IAggregateRoot it will work only with the accessable entities , ex : you have order & orderItem and you only restrict access to order entites and any change to orderItem can be done through order 🙂

  15. Hi Mukesh
    Thanks for this great article,I am agree that you are saying you are going to build boilerplate that any one can download and can start working.
    Just some question in my mind,thought you can give clear answer on them,because i was working on CQRS but the project was microservice and is very big.
    So can we use CQRS with small projects or it can work good with only big one.

    1. Hi Mohsin, Thanks for the feedback.

      CQRS is something that makes you controllers THIN. It is always a good practise to follow a well-defined architecture for every solution. CQRS with MediatR has quite a lot of advantages like the Pipeline Behaviours and Logging. Answering to your question, It completely depends upon you. If the projects are too small and there is no scope of scalability in the game, you would not even ideally need an architecture. But if there is a chance of requirement changes and additional features / infrastructure, it’s better to use CQRS for future proofing you applications. Also, CQRS makes your application much more readable and maintainable. What do you think about this?

      From my experience, once you start getting comfortable with CQRS, it’s really tough to avoid using it 😀
      Thanks and Regards

  16. Hello,

    Thanks for this great article. I suppose I can’t use UnitOfWork pattern and generic repo even with Onion architecture. Could you confirm (or not)

    thanks,

    1. Hi, Thanks for the feedback!
      Yes, you can definitely use Repository Pattern alongside Onion Architecture. It gives a better separation between your actual database of choice and your data access code. It depends on how organized you want your project to be and how comfortable you are with the patterns.
      Thanks and Regrds

  17. Thanks for this article. I am relatively new to building large programs, I am only 17 years old. For a long time I was looking for material where it will be possible to learn trending technologies in building web applications, and your article is the beginning for me. Thanks again

  18. Good job Mukesh!
    Do you have in mind publish another release of the Full Fledged Clean Architecture Solution for ASP.NET Core 3.1 soon?
    I am very interested and I need the authorization, authentication and seedind DB parts.
    Thanks again for your valuable work.
    Josep

    1. Hi, Thanks a lot for the feedback! Hope you liked the article.
      Yes, As a matter of fact I am already building a Solution for Clean Architecture in ASP.NET Core 3.1 WebApi. It’s like 70% done I would say.
      You can take a look at the repository here – https://github.com/iammukeshm/CleanArchitecture.WebApi
      I am planning to release it in a couple of weeks in a well documented way / One-Click Install Template for Visual Studio 2019.

      Thanks and regards.

  19. Good articles so far. I appreciated & loved the way you shared your knowledge from article to new template, you are one of my inspiration.
    Again, thank you for valuable job.

  20. Hi, I have confused on choosing which architecture is better. which one gives better performance and less complexity,etc in .net core web api. can you share me better architecture name?

  21. Hi Mukesh. Excellent post and Thank you

    But I have a question. Adding EntityFrameworkcore to the application layer, creating a dependency for Entity Framework on the application layer. If I want to change the data access technology later, this would be a barrier. What is the solution for this?

  22. Thanks, Mukesh.

    I recently started to learn .Net Core and found that there is what is called clean architecture and knew nothing about it. You have made it clear and simple though yet not confident with it because I know the coding part will be application-specific and hence will differ here and there. I am pleased with this Onion architecture and I wish to follow it more and more by implementing it in all my projects.

    I will follow your other posts i.e. Authentication, Wrappers, Logging, Processing, e.t.c.

    Can you also do Authorization (I think it will be easy to integrate, but I just think I love your style of coding, so I wish you would show your approach in Authorization/Role-based application with API)

  23. Hi Mukesh, I was new to building API’s with Microservice Architecture using ASP.net Core. I went through your articles and I can say ur aticles are one of the best. Can you please make articles on Logging, Validation and Transactional Behavior. I Know u have explaned the validator Behavior in MediatoR pattern But to keep things for tracking Can you please make an artcle on it.

    Can you please create an article on Identity servers?

  24. your articles are well organized with deep details. keep it up. I am salute your time and efforts to share articles.

  25. Hi,
    Thanks for your post :),
    Why do you put interfaces in application service layer? We could put them in the domain core layer, and it is a more abstract approach !
    Something that Steve smith mentioned in this post, All interfaces like services interfaces and repositories interfaces placed in inner center area of domain.

    https://docs.microsoft.com/en-us/dotnet/architecture/modern-web-apps-azure/common-web-application-architectures#clean-architecture

  26. It’s my first time at this website but oh man am I stunned. This is a great article and very clean implementation, cheers to you

  27. Hi Mukesh,

    A great article indeed.
    I just wonder and want to know why all the samples we found with Entity framework? I have a big project to start and wish to write the logic in SQL stored procedures. Stored procedures because we find the easy maintenance and also easy to write the logic. And for this, wish to use ADO.Net without entity framework.
    What would you suggest ?

    1. In practical scenarios, you would actually want both EFCore and RAW SQL Queries for optimal performance. While ADO.NET is super fast, it’s very ideal for long queries with tons of joins. Whereas, EFCore comes with a lot features without compromising much on the performance. It gives a nice abstraction over the DB Provider as well. Meaning you can switch to another database technology with ease.

      So, ultimately there is no actual answer. It all depends on your application design and performance optimization. But you will surely end up having both EF and ADO.NET working side by side.

      Regards.

  28. Really cool, Mukesh.

    As a newbie in .NET, I would like to use this architecture in a personal project with a twist:
    I already built the DB Model in SQL Server (all entities and constraints) and would like to use EF Data First as the starting point for the persistence layer – I may later make some changes in the classes created by EF Data First, which will be migrated to the DB.
    How should I do that? What would be the step-by-step using this architecture?

    Thanks

  29. excelente articulo. encontré el sitio por casualidad y me he leído las publicaciones que en su mayoría son muy interesantes y que no suele haber mucho por internet y además de todo con ejemplos claros y fáciles de seguir, para los principiantes que estamos iniciando en las arquitecturas empresariales y deseamos aprender a implementarlo en nuestros proyectos sin depender de un senior o simplemente seguir mejorando como programadores. saludos desde México, seguir asi!)

  30. Brilliant
    Amazing
    Thank you very much for every article
    I’m reading each article and implement with your clear steps and I am surprised every time with that super powerful results

  31. Hi nice blog, but I got lost a bit on the EF section, would be nice if you have a video version of this

  32. Thanks for this contribution, I find it very practical when it comes to understanding it and I think my code will improve with these practices. Greetings from Argentina

  33. Good stuff, well explained.

    Quick note: SaveChanges should SaveChangesAsync so that the copied code from github matches.

    Note for readers: This whole walk-thorugh works well for .Net Standard 2.0 core libs, for those who prefer to avoid the dll hell when linking to other (typically infra) libs that don’t have 2.1 builds. You’ll just need to use the 3.1.xxx versions (instead of 5.0.xxx) of various EF libs.

  34. Thanks for the walkthrough, great information as always.
    However, as a newcomer, I don’t know how to go about consuming the Api in an UI. Do you have any good resources to explain that process?

    Sincerely,
    Nicolas

  35. I really want to appreciate you sir for pooling out a rich content like this, I followed your content as a guild to solved practical assessment given to me and I got a job of junior .NET Developer. Thanks a lot, am so happy today, I will ever be grateful to you for such a great content

  36. Good Day !

    hai Mukesh ,

    recently I found your blog and it was extremely fantastic effort you are doing.
    I am also a .Net developer working in N-Tier architecture. Your tutorial about Asp.Net core Onion architecture helped me a lot to learn.I would like ask some small doubts to improve my knowledge on asp.net core onion architecture.Can you please share how to create a function in “GetProductByIdQuery.cs” to join multiple tables from database using EF Code First

    Thanks in advance

  37. Hi Mukesh,

    Nice article and great content. Could you please show us how to create unit tests within the context of this implementation (Onion architecture + CQRS + MediatR)
    I would appreciate that a lot

  38. Hi Mukesh, i was trying to implement the above code,
    Got stuck, in which project should i place ‘public static class DependencyInjection’ this DependencyInjection class

  39. Hi Mukesh. Great job with the architecture and thanks for sharing. There’s a problem with the template however that after authorizing and getting a valid token, the controllers with an [Authorize] attribute do not work, the error says “You are not authorized”. So, identity is not working correctly. Can you try this yourself and see what the problem is? Thank you.

  40. Thank you for this valuable post.
    You’ve said Application layer has Application-specific types and interface. Then why did you use .net standard instead of .Net Core for this layer?

  41. You have explained very well. Can we add Repository instead of using direct DbContext in Commands and Queries?

  42. Hello, I am a .Net architect working for a very very very wealthy company in the USA. I am promoting your framework as a solution. My gut instinct is, they will understand and welcome this initiative. If so, they have so much money, it would not surprise me if they reach out to you to either hire you or contract you. Is that a possibility? We can use the knowledge you have. Thanks.

  43. It could be great if you can update it with .net core 6.0 and include serilog logging, xunit testing

  44. Hello, this is really best tutorial about onion architecture,

    I have questions,

    First, where I put business logic, commonly called service, for example ProductService, where the logic before ProductCreateCommand called?
    Second, I need to add ClosedXML to generate excel, where I can put that? in Application, Domain, or Presentation?

    Thanks

  45. Thanks for the very detailed post.
    I have one concern can you help to explain. I see your comparison between N Layer and Onion architecture and the main difference is to eliminate coupling between layers which exists in N Layer. However, from my experience we can use Dependency Inversion in N Layer also so there is no tight coupling between layers in N Layer architecture. For example, EmployeeControler communicates to EmployeeService through interface, EmployeeService communicates to EmployeeService also through interface…
    My question is what is the main difference between those architectures?