Відео

Hi! That would be the pessimist approach, where you would have to lock the row (there are different type of locks) which could impact the performance of the application. As a general rule, if you wait that type of collisions to appear rarely, it's preferred to use the optimistic approach. But it in the end of the day it's a trade-off and comes down to what you need for your app.

Thanks a lot George!

Hi! Since i don't have yet a solution for sharing the source code, you can download it from google drive: drive.google.com/file/d/16QPxheaIt57G2MKicC3KuwBv1wH_AalW/view

Glad I could help!

Hi! You can always catch the exception (in a global exception handler for example) and return the appropriate message. Just retrying will not change anything since the row in the database will have a different version, which is also the point. You can retry to update some of the values, IF that's something you want. More details about that here: learn.microsoft.com/en-us/ef/core/saving/concurrency?tabs=data-annotations

@@spyroskatsios thank you for the explanation.

Hi! Thank you for your kind words! I didn't get exactly the problem, but maybe you want to take a look at transaction isolation levels?

What do you mean ' all the calls to that API are unauthenticated' ??

@@spyroskatsios Just the first call to the API are Authenticated, because the cache it's resolved before the authentication, so, meanwhile the call it's cached, the authentication it's bypassed

@@Tefery It's not resolved before the authentication. The Authentication Middleware is before the cache one. Maybe you are looking at the order of the Attributes? If yes, the order of middleware components in the request pipeline is the one that matters.

@@spyroskatsios True, I just had to add the cache after adding the authentication instead of adding it at the beginning 🤣🤣

Glad i could help 😊

Hi! Since i don't have yet a solution for sharing the source code, you can download it from google drive: drive.google.com/file/d/1hZLSkDMGZw5DGfyYlwauR3Ysi9Qqbp1f/view?usp=sharing

Thanc​@@spyroskatsios

I don't get exactly what you want to achieve, but the erroror as every result pattern library have the usage of returning some kind of union (one or the other), so if you are using a method that returns void, you are not using the library

So in void method we can't have error or what?

You can use ErrorOr<Success> so you can return Success if not failed and the error otherwise.

Thank you very much!

Thank you! 😊

Wow, thanks! 😀

Hi! The middleware serves the purpose of having everything in a single transaction. So, I guess you can have a transaction whenever you need and publish the events inside of it.

Glad it was helpful!

Thanks a lot! 😊

Thank you! Is that what you're looking for? ua-cam.com/video/DUSPIBRjtog/v-deo.htmlsi=l5uD9BeDuyYc1v_4

@@spyroskatsios Yes! thank you very much

Hi! I would go with a different approach. Instead of using the DBContextFactory I would use the DbContext as in any other app, but i would create a different scope each time I wanted to call a service. Also, if I was going to use Mediatr I would create my own Dispatcher which would be just a wrapper of creating a scope and calling the IMediatr.

@@Lazzerman42 I explain what's the issue with scoped services in Blazor in a dedicated video which I have in the description and I mention in my video. Having said that, you could argue about the quality of my video and how well I communicate how Blazor behaves, since those videos were some of my first ones. Maybe at some time in the future I will remake them and have some diagrams as well.

@@spyroskatsios Thanks! Found this, ua-cam.com/video/CalH0TJrhp8/v-deo.html Together with your video it now seems clear. You don't want a long lived DB Context that is used by many different functions, since the context will "collect error, tracking and concurrency state" over time

Thank you very much! :)

Thank you! 😊

You're welcome! 😊

Thank you so much for your kind words! Unfortunately, my audience is at the time very small, so i can't dedicate the time for a full course. Having said that, I'm preparing a project with concepts (among some of those I talk on my videos) like DDD, microservices, token auth (including refresh tokens) and others! Althought I can't go step by step on videos, I'll let you all know when I upload it on github (hopefully before autumn) and probably I'll make an overview video about it.

You're very welcome!

Hi! I suppose you could, but in what form are you going to store them?

@@spyroskatsios now i try to study Drools. but dont know how to install and integrate with eclipse (java). so i not sure c# also have rule engine that can keep rules in configuration file, xml or database or not?

Thanks! Glad you liked it!

You can still use it, but since it's a 'contract' for not returning anything, this update removes unnecessary code!

@@spyroskatsios OK cool thanks

Newer videos have bigger font size!

Thanks 😊

Thanks a lot man!!!

Thank you very much! 😊

Really appreciate it man!

If you are talking about manually invalidating it, didn't fit in the logic of that video!

@@spyroskatsios yeah that’s the one. Cool, looking forward to your next video :)

Thank you for your consistent kind words! 😊

Of course! github.com/spyroskatsios/UA-cam-SearchFilters

@@spyroskatsios you are a super star :)

I like your solution! Thanks for your kind words!

You are very welcome!

You are right! You want to have a mechanism of handling domain events fails. Wrap in a transaction the process of handling them, if you want the changes to be immediate, wrap in a transaction the process of saving them if you use the outbox pattern with eventual consistency, etc. I wanted to keep it simple and focus only in the publishing with Mediatr side of things!

Thank you!

You're welcome! :)

Thank you very much!

I uploaded it: github.com/spyroskatsios/UA-cam-RulesEngineDemo

thanks @@spyroskatsios

Thanks a lot!

If I don't hear that clicky sound, I don't feel like I'm coding 😂 Thank you!

Because we want to treat them as different entities in the app. The point is that we can have different ones, but still save them on the same table, if we choose to.

You mean without Discriminators? Like two entities that one has a list of the others?

@@spyroskatsios no with Discriminators the same like you how u created Hero that extends person . i want to make manager that extends Person and contains a list<Person> employees for example

@@mohamedal-qadeery6530 doesn't it work with the default way, by adding the List to the Manager?

@spyroskatsios No it didn't work or maybe i did something wrong idk

@@mohamedal-qadeery6530 Add the property to the Manager and also configure it with HasMany inside the ManagerConfiguration.