API Layer (Controllers)
↓
Application Layer (Services)
↓
Domain Layer (Models, Interfaces)
↓
Infrastructure Layer (Repositories)

dotnet new webapi -n UnifiedApiDemo

dotnet add package Microsoft.AspNetCore.Mvc.Versioning
dotnet add package Swashbuckle.AspNetCore
dotnet add package Microsoft.AspNetCore.Authentication.JwtBearer

public class ApiResponse<T>
{
    public int Code { get; set; }
    public string Message { get; set; }
    public T Data { get; set; }
    public DateTime Timestamp { get; } = DateTime.UtcNow;

    public static ApiResponse<T> Success(T data) => new() 
    { 
        Code = 200, 
        Message = "Success", 
        Data = data 
    };
    
    public static ApiResponse<object> Error(int code, string message) => new() 
    { 
        Code = code, 
        Message = message 
    };
}

public class ExceptionMiddleware
{
    private readonly RequestDelegate _next;
    private readonly ILogger<ExceptionMiddleware> _logger;

    public ExceptionMiddleware(RequestDelegate next, ILogger<ExceptionMiddleware> logger)
    {
        _next = next;
        _logger = logger;
    }

    public async Task InvokeAsync(HttpContext context)
    {
        try
        {
            await _next(context);
        }
        catch (Exception ex)
        {
            _logger.LogError(ex, "Global exception occurred");
            await HandleExceptionAsync(context, ex);
        }
    }

    private static Task HandleExceptionAsync(HttpContext context, Exception exception)
    {
        context.Response.ContentType = "application/json";
        context.Response.StatusCode = exception switch
        {
            ValidationException => StatusCodes.Status400BadRequest,
            UnauthorizedAccessException => StatusCodes.Status401Unauthorized,
            _ => StatusCodes.Status500InternalServerError
        };

        return context.Response.WriteAsJsonAsync(ApiResponse<object>.Error(
            context.Response.StatusCode,
            exception.Message
        ));
    }
}

public class ApiResponseFilter : IAsyncResultFilter
{
    public async Task OnResultExecutionAsync(
        ResultExecutingContext context, 
        ResultExecutionDelegate next)
    {
        if (context.Result is ObjectResult objResult)
        {
            var apiResponse = ApiResponse<object>.Success(objResult.Value);
            context.Result = new ObjectResult(apiResponse)
            {
                StatusCode = objResult.StatusCode
            };
        }
        await next();
    }
}

var builder = WebApplication.CreateBuilder(args);

// 添加版本控制
builder.Services.AddApiVersioning(options =>
{
    options.DefaultApiVersion = new ApiVersion(1, 0);
    options.AssumeDefaultVersionWhenUnspecified = true;
    options.ReportApiVersions = true;
});

// 配置 Swagger
builder.Services.AddSwaggerGen(c =>
{
    c.SwaggerDoc("v1", new OpenApiInfo { Title = "Unified API", Version = "v1" });
});

// 添加統(tǒng)一響應(yīng)過濾器
builder.Services.AddControllers(options =>
{
    options.Filters.Add<ApiResponseFilter>();
});

// 配置 JWT 認(rèn)證
builder.Services.AddAuthentication(JwtBearerDefaults.AuthenticationScheme)
    .AddJwtBearer(options => 
    {
        options.TokenValidationParameters = new TokenValidationParameters
        {
            ValidateIssuer = true,
            ValidIssuer = "your_issuer",
            ValidateAudience = true,
            ValidAudience = "your_audience",
            ValidateLifetime = true,
            IssuerSigningKey = new SymmetricSecurityKey(Encoding.UTF8.GetBytes("your_secret_key"))
        };
    });

var app = builder.Build();

// 中間件管道
app.UseSwagger();
app.UseSwaggerUI();
app.UseMiddleware<ExceptionMiddleware>();
app.UseAuthentication();
app.UseAuthorization();
app.MapControllers();
app.Run();

[ApiController]
[Route("api/v{version:apiVersion}/[controller]")]
[ApiVersion("1.0")]
[Authorize]
public class ProductsController : ControllerBase
{
    [HttpGet("{id}")]
    [ProducesResponseType(typeof(ProductDto), 200)]
    public IActionResult GetProduct(int id)
    {
        var product = new ProductDto { Id = id, Name = "Sample Product" };
        return Ok(product);
    }

    [HttpPost]
    [ValidateModel]
    public IActionResult CreateProduct([FromBody] ProductCreateDto dto)
    {
        // 業(yè)務(wù)邏輯
        return CreatedAtAction(nameof(GetProduct), new { id = 1 }, null);
    }
}

public class ProductCreateDto
{
    [Required]
    [StringLength(100)]
    public string Name { get; set; }

    [Range(0, 10000)]
    public decimal Price { get; set; }
}

public class ValidateModelAttribute : ActionFilterAttribute
{
    public override void OnActionExecuting(ActionExecutingContext context)
    {
        if (!context.ModelState.IsValid)
        {
            var errors = context.ModelState
                .Where(e => e.Value.Errors.Count > 0)
                .ToDictionary(
                    kvp => kvp.Key,
                    kvp => kvp.Value.Errors.Select(e => e.ErrorMessage).ToArray()
                );
            
            context.Result = new BadRequestObjectResult(
                ApiResponse<object>.Error(400, "Validation Error", errors)
            );
        }
    }
}

{
  "code": 200,
  "message": "Success",
  "data": {
    "id": 1,
    "name": "Sample Product"
  },
  "timestamp": "2024-02-20T12:34:56Z"
}

{
  "code": 400,
  "message": "Validation Error",
  "data": {
    "Price": ["The field Price must be between 0 and 10000."]
  },
  "timestamp": "2024-02-20T12:35:10Z"
}