Tagged articles - ASP.NET Core

Patterns, conventions and standards are invented and enforced in order to make coding easier and more understandable for the developers, but in some cases certain patterns and conventions do not couple so easily and you have to rely on more on the actual technology you are using in order to overcome these complications. One of the cases this happens is using CQRS, especially commands and REST...read more

Swagger is the most convenient way to document your REST api endpoints. It provides generating of documentation on the fly based on the code structure, which shortens the time of creating the documentation drastically...read more

Recently I wrote an article about Automatic CQRS handler registration in ASP.NET Core with reflection in order to reduce number of lines for registering command and query to IOC container in ASP.NET Core. However, this solution does reduce lines for service registration in the startup, you still need to add all command and query handlers as parameters to the controller constructor. ...read more

Command Query Responsibility Segregation (CQRS) pattern is one of my favorite way of handling the Web API requests for a simple reason that is clearly separates reading and writing. Quite often at some stage of the project you will hit the performance bottlenecks which are most probably cause by the way you are reading ow writing your data. CQRS splits reading and writing so that you can independently use different persistence framework for reading and writing...read more

Since REST services do not have the UI, there is not much space for the localization. Data is sent and retrieved and most of the decisions is made based on the status code of the response...read more

Swagger is a great way to document you REST API endpoints and reduce the need for communication, item spent and the cost for supporting the consumers of you APIs. Apart from providing the info about the endpoints, models, validation it can also display the data of the product...read more

Authentication is an essential component of pretty much any REST API. Most of the resources you expose through REST API services, unless they are protected inside intranet, need to be protected by some kind of authentication. This is pretty much clear and it is easy achieved by just simply decorating your controller actions or even whole controllers with Authorize or AllowAnonymous attributes. ...read more

Contracts, models or DTOs, call them how ever you want, are your connection with the outside world from your REST API. Consumers of your API depend on them and they know what to expect or what your API endpoints expect in communication...read more

Implementing partial updates on the REST API is probably the trickiest method to implement. Unlike PUT HTTP method where you pass the whole DTO when you are updating an entity, PATCH method is intended to update only one or few properties of the entity you want to apply change to...read more

Paging a REST API response is equally important as filtering the data returned through REST API endpoints and they quite often come together. Just like filtering, paging limits the amount of data returned from the endpoint, saving both client and server side resources...read more

Starting from .NET Core version 2.1, there are so far three types of WebApi responses that controller actions can return. All three types had it's own pros and cons but all are lacking in options to satisfy both REST and the high level of testability. The available response types in ASP.NET Core including recently released 2.2 version are ...read more

Starting from it's initial release ASP .NET Core comes with built in dependency injection (DI) to help implement Inversion Of Control design pattern. This is not something new in .NET and apart from built-in DI in .NET Core, there are other libraries which provide same and in some cases even more advanced dependency injection implementation...read more

When running ASP.NET Core application as self-hosted using Kestrel, it will by default use port 5000 for listening for requests. This should not be a big issue since you can always proxy requests to port 5000. Problem occurs when you might want to have multiple applications on one host, or you simply cannot use port 5000 for security or any other reasons.Luckily, default port for ASP.NET Core application running on Kestrel can be easily changed, but in order to make it easily configurable there are few changes you need to make in your code in order to access IHostingEnvironment and IConfiguration implementation instances combined. ...read more

Model validation is an important part of request life-cycle and pipeline in MVC Core regardless whether you are building Web API project or ASP.NET MVC web application. Both project templates rely on the common ASP.NET Core platform therefore validation is pretty much the same in both type of projects. Because Web API and micro services are more popular nowadays, I am going to use Web API sample project to demonstrate how to modify validation response in MVC Web API Core project. ...read more

Apart from adding your own middleware to the ASP.NET MVC Core application pipeline, you can control the response using custom MVC filter attributes and selectively apply them to either whole controller or controller actions. One of the commonly used MVC filter in ASP.NET Core is ExceptionFilterAttribute for handling error response in Wep API applications. It is easy to implement and I also wrote an article about Error handling in ASP.NET Core Web API few months ago...read more