基于 .NET 8 Web API 的 RabbitMQ 消息队列应用

步骤 3.创建项目，并请检查并确认该项目是.net 8 框架。

开始编码

添加 NewFolder 调用模型，并添加名为 Product.cs 的产品模型类。

namespace RabbitMQProductApi.Models
{
    public class Product
    {
        public int ProductID { get; set; }
        public string ProductName { get; set; } = string.Empty;
        public string ProductDescription { get; set; } = string.Empty;
        public int ProductPrice { get; set; }
        public int ProductStock { get; set; }
    }
}

添加 NewFolder 调用 RabbitMQ，添加 RabbitMQ 接口名称同 IRabbitMQProducer.cs。

namespace RabbitMQProductApi.RabbitMQ
{
    public interface IRabbitMQProducer
    {
        public void SendProductMessage<T>(T message);
    }
}

添加一个新的 RabbitMQProducer 类并使用 IRabbitMQProducer 接口。请从 nuget.org 安装最新的 RabbitMQ.Client。

using RabbitMQ.Client;

namespace RabbitMQProductApi.RabbitMQ
{
    public class RabbitMQProducer : IRabbitMQProducer
    {
        public void SendProductMessage<T>(T message)
        {
            var factory = new ConnectionFactory() { HostName = "localhost" };
            var connection = factory.CreateConnection();
            var channel = connection.CreateModel();
            channel.QueueDeclare(queue: "ProductQueue", durable: false, exclusive: false, autoDelete: false, arguments: null);
            var json = System.Text.Json.JsonSerializer.Serialize(message);
            var body = System.Text.Encoding.UTF8.GetBytes(json);
            channel.BasicPublish(exchange: "", routingKey: "ProductQueue", basicProperties: null, body: body);
        }
    }
}

添加一个名为 Data 的新文件夹（用于数据库目的），请确保您已使用 nuget.org 为该项目安装了 实体框架。

using Microsoft.EntityFrameworkCore;
using RabbitMQProductApi.Models;

namespace RabbitMQProductApi.Data
{
    public class DBContextClass : DbContext
    {
        protected readonly IConfiguration Configuration;
        public DBContextClass(IConfiguration configuration)
        {
            Configuration = configuration;
        }
        protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
        {
            optionsBuilder.UseSqlServer("Server=Machine Name;Database=ProductDB;Trusted_Connection=True;");
            optionsBuilder.UseSqlServer(Configuration.GetConnectionString("DefaultConnection"));
        }

        public DbSet<Product> Products { get; set; }
    }
}

添加 NewFolder 服务并使用 IProductService.cs 添加服务接口名称。

namespace RabbitMQProductApi.Services
{
    public interface IProductServices
    {
        public IEnumerable<Product> GetProducts();
        public Product GetProduct(int id);
        public Product AddProduct(Product product);
        public Product UpdateProduct(Product product);
        public bool DeleteProduct(int id);
        public bool DeleteProduct(Product product);
    }
}

添加 ProductService.cs 类使用 IProductServices。

namespace RabbitMQProductApi.Services
{
    public class ProductServices : IProductServices
    {
        private readonly DBContextClass _dbContext;
        public ProductServices(DBContextClass dbContext)
        {
            _dbContext = dbContext;
        }

        public IEnumerable<Product> GetProducts()
        {
            return _dbContext.Products.ToList();
        }

        public Product GetProduct(int id)
        {
            return _dbContext.Products.FirstOrDefault(x => x.ProductID == id);
        }

        public Product AddProduct(Product product)
        {
           var result = _dbContext.Products.Add(product);
            _dbContext.SaveChanges();
            return result.Entity;
        }

        public Product UpdateProduct(Product product)
        {
            var result = _dbContext.Products.Update(product);
            _dbContext.SaveChanges();
            return result.Entity;
        }

        public bool DeleteProduct(int id)
        {
           var result = _dbContext.Products.FirstOrDefault(x => x.ProductID == id);
            if (result != null)
            {
                _dbContext.Products.Remove(result);
                _dbContext.SaveChanges();
                return true;
            }
            return false;
        }

        public bool DeleteProduct(Product product)
        {
            var result = _dbContext.Products.FirstOrDefault(x => x.ProductID == product.ProductID);
            if (result != null)
            {
                _dbContext.Products.Remove(result);
                _dbContext.SaveChanges();
                return true;
            }
            else
            {
                return false;
            }
        }
    }
}

添加迁移脚本，在包管理器控制台中执行以下命令。

add-migration "ProductMigration"

然后通过传递以下命令来更新数据库。

update-database

生成的迁移脚本内容如下：

protected override void Up(MigrationBuilder migrationBuilder)
{
    migrationBuilder.CreateTable(
        name: "Products",
        columns: table => new
        {
            ProductID = table.Column<int>(type: "int", nullable: false)
                .Annotation("SqlServer:Identity", "1, 1"),
            ProductName = table.Column<string>(type: "nvarchar(max)", nullable: false),
            ProductDescription = table.Column<string>(type: "nvarchar(max)", nullable: false),
            ProductPrice = table.Column<int>(type: "int", nullable: false),
            ProductStock = table.Column<int>(type: "int", nullable: false)
        },
        constraints: table =>
        {
            table.PrimaryKey("PK_Products", x => x.ProductID);
        });
}

/// <inheritdoc />
protected override void Down(MigrationBuilder migrationBuilder)
{
    migrationBuilder.DropTable(
        name: "Products");
}

现在添加 NewFolder，以控制器命名，并添加 ProductController.cs。

namespace RabbitMQProductApi.Controllers
{
    [Route("api/[controller]")]
    [ApiController]
    public class ProductController : ControllerBase
    {
        private readonly IRabbitMQProducer _rabbitMQProducer;
        private readonly ILogger<ProductController> _logger;
        private readonly IProductServices _productService;
        public ProductController(ILogger<ProductController> logger, IProductServices productService, IRabbitMQProducer rabbitMQProducer)
        {
            _logger = logger;
            _productService = productService;
            _rabbitMQProducer = rabbitMQProducer;
        }
        [HttpGet("productlist")]
        public IActionResult GetProducts()
        {
            var products = _productService.GetProducts();
            return Ok(products);
        }
        [HttpGet("product/{id}")]
        public IActionResult GetProduct(int id)
        {
            var product = _productService.GetProduct(id);
            if (product == null)
            {
                return NotFound();
            }
            return Ok(product);
        }
        [HttpPost("addproduct")]
        public IActionResult AddProduct([FromBody] Product product)
        {
            var newProduct = _productService.AddProduct(product);
            _rabbitMQProducer.SendProductMessage(newProduct);
            return Ok(newProduct);
        }
        [HttpPut("updateproduct")]
        public IActionResult UpdateProduct([FromBody] Product product)
        {
            var updatedProduct = _productService.UpdateProduct(product);
            return Ok(updatedProduct);
        }
        [HttpDelete("deleteproduct/{id}")]
        public IActionResult DeleteProduct(int id)
        {
            var result = _productService.DeleteProduct(id);
            if (result)
            {
                return Ok();
            }
            return NotFound();
        }

        [HttpDelete("deleteproduct")]
        public IActionResult DeleteProduct([FromBody] Product product)
        {
            var result = _productService.DeleteProduct(product);
            if (result)
            {
                return Ok();
            }
            return NotFound();
        }
    }
}

使用下面的代码更新 Program.cs 类。

namespace RabbitMQProductApi
{
    public class Program
    {
        public static void Main(string[] args)
        {
            var builder = WebApplication.CreateBuilder(args);

            // Add services to the container.
            builder.Services.AddScoped<IProductServices, ProductServices>();
            builder.Services.AddDbContext<DBContextClass>();
            builder.Services.AddScoped<IRabbitMQProducer, RabbitMQProducer>();
            builder.Services.AddControllers();
            // 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();
            }

            app.UseHttpsRedirection();

            app.UseAuthorization();

            app.MapControllers();

            app.Run();
        }
    }
}

现在构建项目并在本地机器上运行它。

将项目添加到产品数据库中。

请检查数据库。

完毕

下一部分将会看到如何在客户端应用程序中使用消息。