.Net Core3.0 WEB API 中使用FluentValidation验证，实现批量注入

为什么要使用FluentValidation

1.在日常的开发中，需要验证参数的合理性，不紧前端需要验证传毒的参数，后端也需要验证参数
2.在领域模型中也应该验证,做好防御性的编程是一种好的习惯（其实以前重来不写的，被大佬教育了一番）
3.FluentValidation 是.NET 开发的验证框架，开源,主要是简单好用，内置了一些常用的验证器，可以直接使用，扩展也很方便

使用FluentValidation

1.引入FluentValidation.AspNetCore NuGet包
2.建立需要验证的类

/// <summary>
/// 创建客户
/// </summary>
public class CreateCustomerDto
{
/// <summary>
/// 客户姓名
/// </summary>
public string CustomerName { get; set; }
/// <summary>
/// 客户年龄
/// </summary>
public string CustomerAge { get; set; }
/// <summary>
/// 客户电话
/// </summary>
public string CustomerPhone { get; set; }
/// <summary>
/// 客户地址
/// </summary>
public Address CustomerAddress { get; set; }
}

/// <summary>
/// 验证
/// </summary>
public class CreateCustomerDtoValidator : AbstractValidator<CreateCustomerDto>
{
public CreateCustomerDtoValidator()
{
RuleFor(x => x.CustomerName)
.NotEmpty()
.WithMessage("客户姓名不能为空");
RuleFor(x => x.CustomerPhone)
.NotEmpty()
.WithMessage("客户电话不能为空");

}
}

3.统一返回验证的信息，ResponseResult为全局统一参数返回的类

/// <summary>
/// 添加AddFluentValidationErrorMessage
/// </summary>
/// <returns></returns>
public DependencyInjectionService AddFluentValidationErrorMessage()
{
_services.Configure<ApiBehaviorOptions>(options =>
{
options.InvalidModelStateResponseFactory = (context) =>
{
var errors = context.ModelState
.Values
.SelectMany(x => x.Errors
.Select(p => p.ErrorMessage))
.ToList();
var result = new ResponseResult<List<string>>
{
StatusCode = "00009",
Result = errors,
Message = string.Join(",", errors.Select(e => string.Format("{0}", e)).ToList()),
IsSucceed = false
};

return new BadRequestObjectResult(result);
};
});
return _dependencyInjectionConfiguration;
}

4.注入验证的类
使用builder.RegisterType().As<IValidator>();比较麻烦每次新增都需要添加一次注入
所以我们使用批量的注入，来减少麻烦,通过反射获取所有的验证的类批量注入

/// <summary>
/// 添加MVC
/// </summary>
/// <returns></returns>
public DependencyInjectionService AddMvc()
{
_services.AddControllers(options =>
{
options.Filters.Add(typeof(LogHelper));
}).AddJsonOptions(options =>
{
//忽略循环引用
//options.JsonSerializerOptions.IgnoreReadOnlyProperties = true;
}).AddFluentValidation(options =>
{
options.RunDefaultMvcValidationAfterFluentValidationExecutes = false;
var validatorList = GetFluentValidationValidator("ConferenceWebApi");
foreach (var item in validatorList)
{
options.RegisterValidatorsFromAssemblyContaining(item);
}
});
return _dependencyInjectionConfiguration;
}

/// <summary>
/// 获取所有的FluentValidation Validator的类
/// </summary>
public IEnumerable<Type> GetFluentValidationValidator(string assemblyName)
{
if (assemblyName == null)
throw new ArgumentNullException(nameof(assemblyName));
if (string.IsNullOrEmpty(assemblyName))
throw new ArgumentNullException(nameof(assemblyName));

var implementAssembly = RuntimeHelper.GetAssembly(assemblyName);
if (implementAssembly == null)
{
throw new DllNotFoundException($"the dll ConferenceWebApi not be found");
}
var validatorList = implementAssembly.GetTypes().Where(e => e.Name.EndsWith("Validator"));
return validatorList;
}

FluentValidation学习的资料

使用FluentValidation
1.在日常的开发中，需要验证参数的合理性，不紧前端需要验证传毒的参数，后端也需要验证参数
2.在领域模型中也应该验证,做好防御性的编程是一种好的习惯（其实以前重来不写的，被大佬教育了一番）
3.FluentValidation 是.NET 开发的验证框架，开源,主要是简单好用，内置了一些常用的验证器，可以直接使用，扩展也很方便

使用FluentValidation

1.引入FluentValidation.AspNetCore NuGet包
2.建立需要验证的类

/// <summary>
/// 创建客户
/// </summary>
public class CreateCustomerDto
{
/// <summary>
/// 客户姓名
/// </summary>
public string CustomerName { get; set; }
/// <summary>
/// 客户年龄
/// </summary>
public string CustomerAge { get; set; }
/// <summary>
/// 客户电话
/// </summary>
public string CustomerPhone { get; set; }
/// <summary>
/// 客户地址
/// </summary>
public Address CustomerAddress { get; set; }
}

/// <summary>
/// 验证
/// </summary>
public class CreateCustomerDtoValidator : AbstractValidator<CreateCustomerDto>
{
public CreateCustomerDtoValidator()
{
RuleFor(x => x.CustomerName)
.NotEmpty()
.WithMessage("客户姓名不能为空");
RuleFor(x => x.CustomerPhone)
.NotEmpty()
.WithMessage("客户电话不能为空");

}
}

3.统一返回验证的信息，ResponseResult为全局统一参数返回的类

/// <summary>
/// 添加AddFluentValidationErrorMessage
/// </summary>
/// <returns></returns>
public DependencyInjectionService AddFluentValidationErrorMessage()
{
_services.Configure<ApiBehaviorOptions>(options =>
{
options.InvalidModelStateResponseFactory = (context) =>
{
var errors = context.ModelState
.Values
.SelectMany(x => x.Errors
.Select(p => p.ErrorMessage))
.ToList();
var result = new ResponseResult<List<string>>
{
StatusCode = "00009",
Result = errors,
Message = string.Join(",", errors.Select(e => string.Format("{0}", e)).ToList()),
IsSucceed = false
};

return new BadRequestObjectResult(result);
};
});
return _dependencyInjectionConfiguration;
}

4.注入验证的类
使用builder.RegisterType().As<IValidator>();比较麻烦每次新增都需要添加一次注入
所以我们使用批量的注入，来减少麻烦,通过反射获取所有的验证的类批量注入

/// <summary>
/// 添加MVC
/// </summary>
/// <returns></returns>
public DependencyInjectionService AddMvc()
{
_services.AddControllers(options =>
{
options.Filters.Add(typeof(LogHelper));
}).AddJsonOptions(options =>
{
//忽略循环引用
//options.JsonSerializerOptions.IgnoreReadOnlyProperties = true;
}).AddFluentValidation(options =>
{
options.RunDefaultMvcValidationAfterFluentValidationExecutes = false;
var validatorList = GetFluentValidationValidator("ConferenceWebApi");
foreach (var item in validatorList)
{
options.RegisterValidatorsFromAssemblyContaining(item);
}
});
return _dependencyInjectionConfiguration;
}

/// <summary>
/// 获取所有的FluentValidation Validator的类
/// </summary>
public IEnumerable<Type> GetFluentValidationValidator(string assemblyName)
{
if (assemblyName == null)
throw new ArgumentNullException(nameof(assemblyName));
if (string.IsNullOrEmpty(assemblyName))
throw new ArgumentNullException(nameof(assemblyName));

var implementAssembly = RuntimeHelper.GetAssembly(assemblyName);
if (implementAssembly == null)
{
throw new DllNotFoundException($"the dll ConferenceWebApi not be found");
}
var validatorList = implementAssembly.GetTypes().Where(e => e.Name.EndsWith("Validator"));
return validatorList;
}

5.使用起来就十分简单了

/// <summary>
/// 创建客户
/// </summary>
/// <param name="input"></param>
/// <returns></returns>
[HttpPost]
public async Task<ResponseResult<string>> CreateCustomer([FromBody] CreateCustomerDto input)
{
var createCustomerCommand = new CreateCustomerCommand(input.CustomerName,input.CustomerAge,input.CustomerPhone,input.CustomerAddress);
await _commandService.SendCommandAsync(createCustomerCommand);
var result = new ResponseResult<string>
{
IsSucceed = true,
Result = "创建客户成功！"
};
return result;
}

FluentValidation学习的资料

感谢大佬们的分享，零度编程中的教程非常的全面，包括了许多的验证器的使用，记不住时直接可以翻阅查看
零度编程：https://www.xcode.me/post/5849
Lamond Lu：https://www.geek-share.com/detail/2759255000.html