使用 OData 在 aspnet Core 中自定义参数绑定属性

Question

我在此处发布了 Ricks "raw request body" 属性的实现...

https://weblog.west-wind.com/posts/2013/dec/13/accepting-raw-request-body-content-with-aspnet-web-api

...我正在将解决方案转换为 .Net Core...

有谁知道如何在 aspNet Core 中将其作为 OData 控制器参数的绑定属性来实现？

编辑：

如果它对任何人有帮助，这是我正在尝试转换的代码...

using System;
using System.Linq;
using System.Threading;
using System.Threading.Tasks;

namespace Core.Api
{
    /// <summary>
    /// An attribute that captures the entire content body and stores it
    /// into the parameter of type byte[].
    /// </summary>
    /// <remarks>
    /// The parameter marked up with this attribute should be the only parameter as it reads the
    /// entire request body and assigns it to that parameter.    
    /// </remarks>
    [AttributeUsage(AttributeTargets.Class | AttributeTargets.Parameter, AllowMultiple = false, Inherited = true)]
    public sealed class RawBodyAttribute : ParameterBindingAttribute
    {
        public override HttpParameterBinding GetBinding(HttpParameterDescriptor parameter)
        {
            if (parameter == null) throw new ArgumentException("Invalid parameter");
            return new RawBodyParameterBinding(parameter);
        }
    }

    public class RawBodyParameterBinding : HttpParameterBinding
    {
        public RawBodyParameterBinding(HttpParameterDescriptor descriptor) : base(descriptor) { }

        public override Task ExecuteBindingAsync(ModelMetadataProvider metadataProvider, HttpActionContext actionContext, CancellationToken cancellationToken)
        {
            var binding = actionContext.ActionDescriptor.ActionBinding;
            if(binding.ParameterBindings.Count(pb => pb.GetType() == typeof(RawBodyParameterBinding)) != 1)
                throw new InvalidOperationException("Exactly one parameter must be marked with the RawBody attribute in the action signature.");

            var type = binding.ParameterBindings.First(pb => pb.GetType() == typeof(RawBodyParameterBinding)).Descriptor.ParameterType;

            if (type == typeof(string))
            {
                return actionContext.Request.Content
                        .ReadAsStringAsync()
                        .ContinueWith((task) => SetValue(actionContext, task.Result));
            }
            else if(type == typeof(byte[]))
            {
                return actionContext.Request.Content
                    .ReadAsByteArrayAsync()
                    .ContinueWith((task) => SetValue(actionContext, task.Result));
            }

            throw new InvalidOperationException("Only byte[] or string values are supported for [RawBody] parameters");
        }

        public override bool WillReadBody
        {
            get { return true; }
        }
    }
}

Answer 1

您需要实现自己的属性和绑定器。

1. RawBodyAttribute

   [AttributeUsage(AttributeTargets.Parameter | AttributeTargets.Property, AllowMultiple = false, Inherited = true)]
   public class RawBodyAttribute : Attribute, IBindingSourceMetadata
   {
       public BindingSource BindingSource => RawBodyBindingSource.RawBody;
   }
   

2. RawBodyBindingSource

   public class RawBodyBindingSource : BindingSource
   {
       public static readonly BindingSource RawBody = new RawBodyBindingSource(
           "RawBody",
           "RawBody",
           true,
           true
       );
   
       public RawBodyBindingSource(string id, string displayName, bool isGreedy, bool isFromRequest) 
           : base(id, displayName, isGreedy, isFromRequest)
       {
       }
   
       public override bool CanAcceptDataFrom(BindingSource bindingSource)
       {
           return bindingSource == Body || bindingSource == this;
       }
   }
   

3. RawBodyModelBinder

   public class RawBodyModelBinder : IModelBinder
   {
       public Task BindModelAsync(ModelBindingContext bindingContext)
       {           
   
           using (StreamReader reader = new StreamReader(bindingContext.HttpContext.Request.Body, Encoding.UTF8))
           {
               var model = reader.ReadToEnd();
               bindingContext.Result = ModelBindingResult.Success(model);
           }
   
           return Task.CompletedTask;
       }
   }
   

4. RawBodyModelBinderProvider

   public class RawBodyModelBinderProvider : IModelBinderProvider
   {
       public IModelBinder GetBinder(ModelBinderProviderContext context)
       {
           if (context.BindingInfo.BindingSource != null
               && context.BindingInfo.BindingSource.CanAcceptDataFrom(RawBodyBindingSource.RawBody))
           {
               return new RawBodyModelBinder();
           }
           else
           {
               return null;
           }
       }
   }
   

5. 注册

   services.AddMvc(options =>
   {
       options.ModelBinderProviders.Insert(0, new RawBodyModelBinderProvider());
   }).SetCompatibilityVersion(CompatibilityVersion.Version_2_2);
   

6. 用例

   public IActionResult Post([RawBody]string value)
   {
       return Ok(value);
   }