What is the Dependency Injection Design Pattern? Dependency Injection is a design pattern used to execute Inversion of control (IoC). It is a process of injecting the dependency object into a class that depends on it. Dependency Injection is the often-used design pattern these days to separate the dependencies between the objects that allow us to implement loosely coupled software components. It allows the making of dependent objects outside of the class and supplies those objects to a class in distinct ways. Let’s talk about the bit-by-bit process to implement dependency Injection in the ASP.Net Core application. The ASP.NET Core Framework provides inbuilt support for Dependency Injection design patterns. It injects the dependency objects to a class via a constructor, method, or property using the built-in IoC container. The inbuilt IoC container is elected by IServiceProvider implementation, which supports default construction injection. The classes managed by built-in IoC Containers are called services. Types of Services in ASP.NET Core There are 2 types of services in ASP.NET core. Framework Services: Services that are a part of the ASP.NET core framework, like IApplicationBuilder, IHostingEnvironment, ILoggerFactory, etc. Application Services: The services you create as a programmer for your application. Before registering services, let’s first know the different methods to register a service. The ASP.NET core gives 3 methods to register a service with a Dependency Injection container. The method that we use to register a service will determine the lifetime of the service. Singleton: A Singleton service is created only once per application lifetime. The same instance is used all over the application. Common uses contain configuration services, logging, or other services where a single instance is enough and advisable. Since the same instance is used throughout, you need to ensure that Singleton services are thread-safe. Not suitable for saving user-specific data or request-specific data. This can be reached by adding the service as a singleton through the AddSingleton method of the IServiceCollection. Transient: A Transient service is created every time it is requested from the service container. This means that a new instance is provided to every class or method that requires it. Suitable for lightweight, stateless services. Since a new instance is created every time, you don’t need to worry about thread safety related to the internal state. While transient services are simple and provide clean separation, they can be more resource-intensive if they are vast or require significant resources to build. This can be got by adding the service through the AddTransient method of the IServiceCollection. Scoped: A scoped service is created once per client request (means per HTTP request). Perfect for services that need to maintain state within a single request but should not be shared across different requests. This can be achieved by adding the service through the AddScoped method of the IServiceCollection. How to Register a Service with ASP.NET Core Dependency Injection Container? We need to register a service to the in-built dependency injection container with the program class. The below code shows how to register a service with different lifetimes. var builder = WebApplication.CreateBuilder(args); // ADD FRAMEWORK MVC SERVICES TO THE CONTAINER builder.Services.AddMvc(); // ADD APPLICATION SERVICES TO THE CONTAINER builder.Services.Add(new ServiceDescriptor(typeof(ISubjectTypesDA), new SubjectTypesDA())); // BY DEFAULT SINGLETON builder.Services.Add(new ServiceDescriptor(typeof(ISubjectTypesDA), new SubjectTypesDA(),ServiceLifetime.Singleton)); // SINGLETON builder.Services.Add(new ServiceDescriptor(typeof(ISubjectTypesDA), new SubjectTypesDA(),ServiceLifetime.Transient)); // TRANSIENT builder.Services.Add(new ServiceDescriptor(typeof(ISubjectTypesDA), new SubjectTypesDA(),ServiceLifetime.Scoped)); // SCOPED What is the ServiceDescriptor class in .NET Core? This class speaks for a descriptor of a service in the DI Container. It essentially describes how to service should be instantiated and managed by the container. So, it describes a service, including its lifetime, the service type, and the implementation type. Extension methods for Registration ASP.NET Core framework contains extension methods for each type of lifetime: AddSingleton, AddTransient, and AddScoped methods. The below example shows how to register types of lifetimes using extension methods. // ADD APPLICATION SERVICE TO THE CONTAINER. services.AddTransient<IEmailSenderBL, EmailSenderBL>(); // TRANSIENT services.AddScoped<ISubjectTypesBL, SubjectTypesBL>(); // SCOPED services.AddSingleton<ICPCalculationBL, CPCalculationBL>(); // SINGLETON The dependent class is a class which depends on the dependency class. The dependency class is a class that provides service to the dependent class. The interface injects the dependency class object into the dependent class. There are 3 types of Dependency Injection. Constructor Injection Property Injection Method Injection Constructor Injection: we register the service, the IoC automatically executes constructor injection if a service type is included as a parameter in a constructor. Example: public class CenterController : BaseController { private ICenterBL _centerBL; public CenterController(ICenterBL centerBL) : base(myLoginUser) { _centerBL = centerBL; } [Authorize] public IActionResult Index() { try { var data = _centerBL.GetCenterpageList(); return View(data); } catch (Exception EX) { throw EX; } } } Property Injection: Not required to add dependency services in the constructor. We can manually access the services configured with built-in IoC containers using the RequestServices property of HttpContext. public class AddressController : Controller { [Authorize] public IActionResult Index() { var services = this.HttpContext.RequestServices; IAddressBL _address = (IAddressBL)services.GetService(typeof(IAddressBL)); var data = _address.GetAddressList(); return View(data); } } Method Injection: Occasionally, we may only need a dependency object in a single action method. In that case, we need to use the [FromServices] attribute with the service type parameter in the action method. In the below example, you can see we are using the [FromServices] attribute within the Index action method. So, at runtime, the IoC Container will inject the dependency object to the IAddressBL repository reference variable. As we inject the dependency object through a method, it is called method dependency injection. public class CommonController: Controller { public IActionResult Index([FromServices] IAddressBL _addressBL) { var list = _addressBL.GetAddressList(); return View(list); } } Advantages of Dependency Injection Loose Coupling: we can separate our classes from their dependencies. This results in code that is simpler to maintain and test. Testability: we can increase the testability of our code since we can easily replace dependencies with mock objects during unit testing. Extensibility: enhance the extensibility of our code by offering the flexibility to switch out dependencies conveniently. Reusability: makes our code more reusable since we can conveniently share dependencies among various classes.
Simplifying API Responses with AutoWrapper.Core in .NET Core. Handling API responses effectively is a crucial aspect of building robust and user-friendly applications. In .NET Core applications, the AutoWrapper.Core library comes to the rescue, providing a streamlined way to structure and standardize API responses. In this blog post, we'll explore how to use AutoWrapper.Core to create fixed responses for different status codes in your API. Firstly, you'll need to install the AutoWrapper.Core NuGet package. Add the following line to your project's .csproj file: <PackageReference Include="AutoWrapper.Core" Version="4.5.1" /> This package simplifies the process of handling API responses and ensures a consistent format for success, error, and data messages. Example: Login Method Let's consider a common scenario, the login method, where we want to ensure fixed responses for both successful and unsuccessful attempts. [HttpPost("Login")] public async Task<ApiResponse> Login([FromBody] Login model) { var user = await _userService.GetUserByName(model.UserName); if (user != null && await _userService.CheckUserPassword(user, model.Password)) { var userResponse = await _tokenService.GenerateToken(user); return new ApiResponse(message: "Login Successfully.", result: userResponse, statusCode: 200); } return new ApiResponse(message: "Invalid Credential.", result: null, statusCode: 401); } In this example, we're using AutoWrapper.Core's ApiResponse class to encapsulate our responses. For a successful login attempt (status code 200), we return a positive message along with the user response. In case of invalid credentials (status code 401), an appropriate error message is provided. ApiResponse Class Now, let's take a closer look at the ApiResponse class from AutoWrapper.Core: namespace AutoWrapper.Wrappers; public class ApiResponse { public string Version { get; set; } [JsonProperty(DefaultValueHandling = DefaultValueHandling.Ignore)] public int StatusCode { get; set; } public string Message { get; set; } [JsonProperty(DefaultValueHandling = DefaultValueHandling.Ignore)] public bool? IsError { get; set; } public object ResponseException { get; set; } public object Result { get; set; } [JsonConstructor] public ApiResponse(string message, object result = null, int statusCode = 200, string apiVersion = "1.0.0.0") { StatusCode = statusCode; Message = message; Result = result; Version = apiVersion; } public ApiResponse(object result, int statusCode = 200) { StatusCode = statusCode; Result = result; } public ApiResponse(int statusCode, object apiError) { StatusCode = statusCode; ResponseException = apiError; IsError = true; } public ApiResponse() { } } The ApiResponse class provides flexibility in constructing responses with different components such as the message, result, and status code. It helps maintain a standardized format for all API responses. Create a Custom Wrapper: AutoWrapper allows you to create a custom wrapper by implementing the IApiResponse interface. You can create a class that implements this interface to customize the fixed response. Here's an example: Create a Custom Wrapper: AutoWrapper allows you to create a custom wrapper by implementing the IApiResponse interface. You can create a class that implements this interface to customize the fixed response. Here's an example: using AutoWrapper.Wrappers; public class CustomApiResponse<T> : ApiResponse<T> { public string CustomProperty { get; set; } public CustomApiResponse(T result, string customProperty) : base(result) { CustomProperty = customProperty; } } Configure AutoWrapper: In your Startup.cs file, configure AutoWrapper to use your custom wrapper. You can do this in the ConfigureServices method: services.AddAutoWrapper(config => { config.UseCustomSchema<CustomApiResponse<object>>(); }); Replace CustomApiResponse<object> with the custom wrapper class you created. Use Custom Wrapper in Controller Actions: Now, you can use your custom wrapper in your controller actions. For example: [ApiController] [Route("api/[controller]")] public class MyController : ControllerBase { [HttpGet] public IActionResult Get() { // Your logic here var data = new { Message = "Hello, World!" }; // Use the custom wrapper var response = new CustomApiResponse<object>(data, "CustomProperty"); return Ok(response); } } Customize the CustomApiResponse according to your needs, and use it in your controller actions. This way, you can integrate AutoWrapper with other packages and customize the fixed response format in your .NET application. In conclusion, by incorporating AutoWrapper.Core into your .NET Core applications, you can simplify the handling of API responses, making your code more readable, maintainable, and user-friendly. Consider adopting this approach to enhance the overall developer experience and ensure consistency in your API communication.
Are you grappling with performance issues in your project? Look no further—Application Insights is here to help! In this blog post, I'll guide you through the process of configuring and implementing Application Insights to supercharge your application's performance monitoring. Step 1: Installing the Application Insights Package The first crucial step is to integrate the Application Insights package into your project. Simply add the following PackageReference to your project file: <PackageReference Include="Microsoft.ApplicationInsights.AspNetCore" Version="2.22.0" /> And Register service in Program.cs or Startup.cs : builder.Services.AddApplicationInsightsTelemetry(); builder.Services.ConfigureTelemetryModule<DependencyTrackingTelemetryModule>((module, o) => { module.EnableSqlCommandTextInstrumentation = true; }); Add connection string in appsettings.json : "ApplicationInsights": { "InstrumentationKey": "" } This sets the stage for a seamless integration of Application Insights into your application. Step 2: Unleashing the Power of Application Insights Now that the package is part of your project, let's dive into the benefits it brings to the table: 1. Identify Performance Bottlenecks Application Insights allows you to track the execution time of individual stored procedures, queries, and API calls. This invaluable information helps you pinpoint areas that require optimization, paving the way for improved performance. 2. Monitor Database Interactions Efficiently analyze the database calls made by specific APIs within your application. With this visibility, you can optimize and fine-tune database interactions for enhanced performance. 3. Comprehensive Error and Exception Tracking Application Insights goes beyond performance monitoring by providing detailed information about errors, traces, and exceptions. This level of insight is instrumental in effective troubleshooting, allowing you to identify and resolve issues swiftly. Step 3: Integration with Azure for Data Collection and Analysis To maximize the benefits of Application Insights, consider integrating it with Azure for comprehensive data collection and analysis. This step amplifies your ability to make informed decisions regarding performance optimization and problem resolution. In conclusion, Application Insights equips you with the tools needed to elevate your application's performance. By identifying bottlenecks, monitoring database interactions, and offering comprehensive error tracking, it becomes a cornerstone for effective troubleshooting and optimization. Stay tuned for more tips and insights on how to harness the full potential of Application Insights for a high-performing application!