Mastering ASP.NET Core Web API: A Comprehensive Guide to Building, Securing, and Deploying RESTful Services

Mastering ASP.NET Core Web API: A Comprehensive Guide to Building, Securing, and Deploying RESTful Services


ASP.NET Core Web API is a framework for building RESTful web services. It allows us to expose data and business logic to the web using HTTP. In this article, we will learn how to:

  • Create a web API project

  • Add model classes and a database context

  • Scaffold a controller with CRUD methods

  • Configure routing and URL paths

  • Call the web API from a client

  • Add authentication and authorization

  • Deploy the API

Creating the Project

We can create a Web API project in ASP.NET Core using any of these options:

  • Visual Studio

  • Visual Studio Code

  • Visual Studio for Mac

  • .NET CLI

For example, using the .NET CLI we can run:

dotnet new webapi -o TodoApi
cd TodoApi

This will create a new Web API project named TodoApi.

Adding Model Classes

We define model classes to represent the data our API will manage. For example, a TodoItem class:

public class TodoItem 
    public long Id { get; set; } 
    public string Name { get; set; }  
    public bool IsComplete { get; set; }

Adding a Database Context

We create a database context class that derives from DbContext:

public class TodoContext : DbContext
    public TodoContext(DbContextOptions<TodoContext> options)   
        : base(options) { }

    public DbSet<TodoItem> TodoItems { get; set; }

We then register the context with Dependency Injection in Program.cs:

builder.Services.AddDbContext<TodoContext>(opt =>

Scaffolding a Controller

We can scaffold a controller with CRUD methods using:

dotnet aspnet-codegenerator controller ...

This will generate a controller class marked with the [ApiController] attribute and methods to GET, POST, PUT and DELETE todo items.

Configuring Routing

We use attribute routing to define the URL paths for our API. For example:

public class TodoItemsController : ControllerBase
    public IActionResult Get() { ... }

    public IActionResult Get(int id) { ... }

This will map to the URLs:

  • /api/todoitems

  • /api/todoitems/{id}

Calling the API

We can call the API from:

  • JavaScript

  • Postman

  • cURL

  • Mobile clients

For example, using cURL:

curl -X GET "https://localhost:5001/api/todoitems"

Authentication and Authorization

We can secure our API using:

  • JWT Bearer Tokens

  • Azure Active Directory

  • OAuth2 / OpenID Connect (using IdentityServer4)

Deploying the API

We can deploy our API to:

  • Azure App Service

  • AWS Elastic Beanstalk

  • Heroku

  • Docker

Hope this helps! Let me know if you have any other questions.

These Books Will Help You Achieve Web API Excellence!