充分利用对象验证访问完整的JSON

Question

我的Web API暴露下面的方法

[HttpPost] 
public IActionResult MyPostMethod([FromBody]Company company) 
{ 
    ....... 
} 

公司类看起来像下面

public class Company 
    { 
     public Guid CompanyGuid { get; set; } 
     public string Name { get; set; } 
     public List<Employee> Employees { get; set; } 
    } 


[EmployeeValidation] 
public class Employee 
    { 
     public Guid EmployeeGuid { get; set; } 
     public string Name { get; set; } 
    } 

正如你可以看到Employee类装饰有验证属性如下实现。

public class EmployeeValidationAttribute : ValidationAttribute 
    { 
     protected override ValidationResult IsValid(object value, ValidationContext validationContext) 
     { 
      var logger = (ILogger<EmployeeValidationAttribute>)validationContext.GetService(typeof(ILogger<EmployeeValidationAttribute>)); 
      List<Employee> Employees = (List<Employee>)validationContext.ObjectInstance; 

      foreach (Employee Employee in Employees) 
      { 
       if (Employee.EmployeeGuid == Guid.Empty) 
       { 
        return new ValidationResult("Invalid Employee Guid"); 
       } 
      } 
      return ValidationResult.Success; 
     } 
    } 

让出问题的时候与Employee对象的确认说，我要记录整个JSON输入MyPostMethod方法。但是在验证器中，我只能访问员工对象。有反正我能得到验证中获得JSON输入为公司为员工对象？

Answer 1

的validationContext是不会了解公司的情况下任何东西。

你需要建立一个公司验证属性只是雇员而不是一个。

[CompanyValidation] 
public class Company 
{ 
    public String CompanyGuid { get; set; } 
    public string Name { get; set; } 
    public List<Employee> Employees { get; set; } 
} 

public class CompanyValidationAttribute : ValidationAttribute 
{ 
    protected override ValidationResult IsValid(object value, ValidationContext validationContext) 
    { 
     var logger = (ILogger<CompanyValidationAttribute>)validationContext.GetService(typeof(ILogger<CompanyValidationAttribute>)); 
     var company = (Company)validationContext.ObjectInstance; 

     // don't forget to check for null 
     foreach (Employee Employee in company.Employees) 
     { 
      if (Employee.EmployeeGuid == Guid.Empty) 
      { 
       return new ValidationResult("Invalid Employee Guid"); 
      } 
     } 
     return ValidationResult.Success; 
    } 
} 

另一种方法

这里，value参数仅仅是有问题的单个属性但validationContext.ObjectInstance成为容器对象，即公司。

public class MyController : Controller 
{ 
    [HttpPost] 
    public object Post([FromBody]Company company) 
    { 
     if (!ModelState.IsValid) 
     { 
      //log here 
     } 

     return true; 
    } 
} 

public class Company 
{ 
    [GuidValidation] 
    public Guid CompanyGuid { get; set; } 
    public String Name { get; set; } 
    public List<Employee> Employees { get; set; } 
} 

public class Employee 
{ 
    [GuidValidation] 
    public Guid EmployeeGuid { get; set; } 
    public String Name { get; set; } 
} 

public class GuidValidationAttribute : ValidationAttribute 
{ 
    protected override ValidationResult IsValid(object value, ValidationContext validationContext) 
    { 
     if (value != null && validationContext.ObjectInstance != null) 
     { 
      var model = (Guid)value; 

      if (model == Guid.Empty) 
      { 
       return new ValidationResult("Guid cannot be empty."); 
      } 
     } 

     return ValidationResult.Success; 
    } 
}