Posts

ASP.NET Core 9: File Upload using APIs with IFormFile and Anti-Forgery Token

-
Image
In this micro article, we will be discussing the important change in File Upload feature in ASP.NET Core 9 for IFormFile. I have already written an article for File upload using Minimal APIs on this link . This article is an enhancement in that article. In ASP.NET Core 9, a strict anti-forgery validation for file uploads for IFormFile. While using Minimal APIs endpoints, for file upload using IFormFile or IFormFileCollection, we need to pass an Anti-Forgery token into the HTTP request header. This token will be validated before completing the file upload operations.   The Minimal API must use the Anti Forgery Token Service as well as the Anti Forgery Token Middleware else the exception will be thrown. The reason behind the change is for the security precaution for the API that consumes data posted form the form. Although we can disable the Anti Forgery token it is not recommended, please avoid it for the production.  In the Minimal API project created with ASP.NET Core 9,...
Read more

ASP.NET Core: Using YARP (Yet Another Reverse Proxy) for ASP.NET Core Apps to create API Gateways

-
Image
In this article, we will understand and use the YARP (Yet Another Reverse Proxy). This is highly customizable reverse proxy library for .NET. This is especially designed to provide easy but yes secure, scalable, flexible and robust framework for modern ASP.NET Core API Applications. The ASP.NET Core is one of the bests technologies to design, develop highly powerful, secure, and high performant web applications. Being a cross-platform technology, we can build complex server-side solutions using ASP.NET Core. Once of such complex solution is building Microservices application or the server-side application with multiple autonomous APIs. In such solutions we need to host these Microservices or autonomous APIs on separate hosts with separate IP addresses. With multiple services/API hosted, the client application like Browser Clients or Mobile Clients need to know host addresses of each of the service. This increases the complexity of the entire solution. E.g. if any of the service is chan...
Read more

ASP.NET Core 9: Implementing Distributed Caching using SQL Server

-
Image
ASP.NET Core is one of the best technologies for building modern web apps. Since it is cross-platform and lightweight, it's been used by several applications and products for building applications. Most of these applications are high-traffic and they run on multi-server deployment with load-balanced across these servers. In such environments managing data traffic for reading data from database server(s) with respect to various requests could be a challenge. In the deployment architecture the data availability must be guaranteed. Another important features of ASP.NET Core is that the use of ASP.NET Core in Microservices architectures. In case of Microservices, it is important to part of the application pattern to share data across Microservices using Asynchornous communication across them.  To handle the high data availability as well as data communication across Microservices implementation in ASP.NET Core applications, we should consider using the Caching feature of ASP.NET Core. ...
Read more

.NET 8: Task Chaining and Exception Handling while using Tasks

-
Image
This is a go-back article for .NET Developers. The Task Parallel Library (TPL) was introduced long back in .NET Framework 4.0. The TPL have simplified the Threading. Several developers those who have faced challenges while using Threading for concurrent as well as Asynchronous programming, the TPL have made the programming easy and maintainable. The TPL provides several classes but very frequently used classes are Task and Parallel classes. The Task class in C# is part of the System.Threading.Tasks namespace and is used for handling asynchronous programming. Task class represents an operation that executes asynchronously and returns a result in the future.  The Task class have following features: Asynchronous Execution : Helps to run operations asynchronously without blocking the main thread. Parallel Processing : Supports concurrent execution. Chaining Tasks : Enables execution of dependent tasks using the ContinueWith method. Exception Handling : Provides built-in error managemen...
Read more

ASP.NET Core 9: Localized Response from ASP.NET Core 9 API

-
Image
When building enterprise applications, it is highly important to support different language and localized settings. Recently, while discussing with one of my student, a point raised on the multi-lingual response management from the API applications. The need was to send the response from the API based on the local language settings sent to it in the HTTP request. One of the benefits of the ASP.NET Core is an easy support for Localization using the Middleware. The UseRequestLocalization() Middleware is used to configure the Localization options so that the API can be configured to use the Localized resource before sending the response. The RequestLocalizationOptions  class is used to set the configuration for default culture that can be changed while processing the request based on the Accept-Language header received from the HTTP Request. How the Localization is handled in ASP.NET Core Figure 1, explains the localized response processing Figure 1: The Localized Response Processing ...
Read more

Angular: Creating Dynamically Updating Chart with ng2-charts and chart.js with capacilities of Rxjs

-
I wrote an article on creating Real-Time Charts using SignalR and Blazor . After reading this article, some of my students were looking for the same chart in Angular, so I decided to write on this topic. In Angular, we can use JavaScript timer functions, e.g., setInterval(), to call the server side to fetch data and process it on the client side. But instead of using such a JavaScript function, we should use  RxJs  to handle time-based or time-bound operations. What is RxJs?   RxJS, or Reactive Extensions for JavaScript, is a library for composing asynchronous and event-based programs using observable sequences. RxJs provides a powerful and flexible way to handle data streams and asynchronous events that makes it easier and smarter to manage complex asynchronous tasks in JavaScript applications.      Following are some of the most important key features of RxJs: Observables: They represent data streams. These data steams can be observed and manipulate...
Read more

Python: Creating REST APIs using Flask and SQLAlchemy

-
Image
In the previous article , I covered database access from the Python application using the SQLAlchemy package. In this article, we will implement the REST APIs in Python using the Flask framework.  What is Flask? Flask is a popular microweb framework that is written in Python. It is designed to be lightweight and modular, which makes it easy to create web applications quickly. It provides all those essentials needed to build a web app, such as routing, request handling, and templates while allowing developers the freedom to choose additional libraries and tools based on their needs. Following are some of the important Flask objects: The request Object The request object in Flask is used to handle incoming request data. This contains all the data sent by the client in an HTTP request including form data, query parameters, headers, cookies, etc. Following are some common attributes and methods of the request object: request.method : The HTTP method used for the request (e.g., GET, P...
Read more