Minimal API using .NET Core 6 Web API

#dotnet #csharp #webap #webdev

We will discuss minimal APIs in .NET Core 6, their purpose, and step-by-step implementation.

Agenda

Introduction
Step-by-Step Implementation using .NET Core 6

Prerequisites

.NET Core 6 SDK
Visual Studio 2022
SQL Server

Introduction

Minimal APIs are used to create HTTP APIs with minimum dependencies and configuration.
Mostly it is used in microservices that have fewer files and functionality within a single file
But there are a few things that are not supported in minimal APIs like action filters, and built-in validation, also, a few more that are still in progress and will get in the future by .NET Team.

Step-by-Step Implementation using .NET Core 6

Step 1

Create a new .NET Core Web API

Step 2

Configure your project

Step 3

Provide additional information as I showed below

Step 4

Install the following NuGet packages

Project structure

Step 5

Create a Product class inside the entities folder

namespace MinimalAPIsDemo.Entities
{
    public class Product
    {
        public int ProductId { get; set; }
        public string ProductName { get; set; }
        public string ProductDescription { get; set; }
        public int ProductPrice { get; set; }
        public int ProductStock { get; set; }
    }
}

Step 6

Next, create DbContextClass inside the Data folder

using Microsoft.EntityFrameworkCore;
using MinimalAPIsDemo.Entities;
namespace MinimalAPIsDemo.Data
{
    public class DbContextClass : DbContext
    {
        protected readonly IConfiguration Configuration;
        public DbContextClass(IConfiguration configuration)
        {
            Configuration = configuration;
        }
        protected override void OnConfiguring(DbContextOptionsBuilder options)
        {
            options.UseSqlServer(Configuration.GetConnectionString("DefaultConnection"));
        }
        public DbSet<Product> Product { get; set; }
    }
}

Step 7

builder.Services.AddDbContext<DbContextClass>();

Step 8

Add database connection string inside the app settings file

{
  "Logging": {
    "LogLevel": {
      "Default": "Information",
      "Microsoft.AspNetCore": "Warning"
    }
  },
  "AllowedHosts": "*",
  "ConnectionStrings": {
    "DefaultConnection": "Data Source=DESKTOP;Initial Catalog=MinimalAPIDemo;User Id=sa;Password=database;"
  }
}

Step 9

Later on, add different API endpoints inside the Program class with the help of Map and specified routing pattern as I showed below

using Microsoft.EntityFrameworkCore;
using MinimalAPIsDemo.Data;
using MinimalAPIsDemo.Entities;
var builder = WebApplication.CreateBuilder(args);
// Add services to the container.
builder.Services.AddDbContext<DbContextClass>();
// Learn more about configuring Swagger/OpenAPI at https://aka.ms/aspnetcore/swashbuckle
builder.Services.AddEndpointsApiExplorer();
builder.Services.AddSwaggerGen();
var app = builder.Build();
// Configure the HTTP request pipeline.
if (app.Environment.IsDevelopment())
{
    app.UseSwagger();
    app.UseSwaggerUI();
}
//get the list of product
app.MapGet("/productlist", async (DbContextClass dbContext) =>
{
    var products = await dbContext.Product.ToListAsync();
    if (products == null)
    {
        return Results.NoContent();
    }
    return Results.Ok(products);
});
//get product by id
app.MapGet("/getproductbyid", async (int id, DbContextClass dbContext) =>
{
    var product = await dbContext.Product.FindAsync(id);
    if (product == null)
    {
        return Results.NotFound();
    }
    return Results.Ok(product);
});
//create a new product
app.MapPost("/createproduct", async (Product product, DbContextClass dbContext) =>
{
    var result = dbContext.Product.Add(product);
    await dbContext.SaveChangesAsync();
    return Results.Ok(result.Entity);
});
//update the product
app.MapPut("/updateproduct", async (Product product, DbContextClass dbContext) =>
{
    var productDetail = await dbContext.Product.FindAsync(product.ProductId);
    if (product == null)
    {
        return Results.NotFound();
    }
    productDetail.ProductName = product.ProductName;
    productDetail.ProductDescription = product.ProductDescription;
    productDetail.ProductPrice = product.ProductPrice;
    productDetail.ProductStock = product.ProductStock;
    await dbContext.SaveChangesAsync();
    return Results.Ok(productDetail);
});
//delete the product by id
app.MapDelete("/deleteproduct/{id}", async (int id, DbContextClass dbContext) =>
{
    var product = await dbContext.Product.FindAsync(id);
    if (product == null)
    {
        return Results.NoContent();
    }
    dbContext.Product.Remove(product);
    await dbContext.SaveChangesAsync();
    return Results.Ok();
});
app.Run();

Step 10

Run the following entity framework command to create migration and update the database

add-migration "initial"
update-database

Step 11

Finally, run your application