Question

文档非常稀少，我尝试的所有结果都注入了反序列化器，但普通的odata url不再起作用。

https://github.com/OData/WebApi/issues/158的解决方案适用于5.6。

最终相关评论为：

@dbenzhuser-在该提交中，查看ODataFormatterTests.cs以了解如何注入自定义解串器/解串器提供程序。您仍然可以使用一个自定义的DeserializerProvider，但它是通过DI而不是注入的通过ODataMediaTypeFormatters注入它。

这是毫无意义的。我在那里尝试了代码，但正如我所说的那样，它破坏了URL。

现在我的Odata设置很简单：

    services.AddMvc()
        .SetCompatibilityVersion(CompatibilityVersion.Version_2_1);
    services.AddOData();

\ UnitTest \ Microsoft.AspNet.OData.Test.Shared \ Formatter \ ODataFormatterTests.cs

有示例将其注入（例如379-383行）

        config.MapODataServiceRoute("IgnoredRouteName", null, builder =>
            builder.AddService(Microsoft.OData.ServiceLifetime.Singleton, sp => ODataTestUtil.GetEdmModel())
                .AddService<ODataSerializerProvider>(ServiceLifetime.Singleton, sp => new CustomSerializerProvider())
                .AddService<IEnumerable<IODataRoutingConvention>>(ServiceLifetime.Singleton, sp =>
                    ODataRoutingConventions.CreateDefaultWithAttributeRouting("IgnoredRouteName", config)));

但是我似乎无法在不删除核心odata路由的情况下完成此工作。

有人知道如何在不破坏基本功能的情况下将其用于当前版本吗？

Answer 1

如果要维护基本功能，则分三个步骤：

您的 DeserializerProvider 实现应默认为自定义 Deserializer 无法管理的所有方案的基本实现。在下面的示例中，自定义解串器仅在“资源”而不是“集合”上运行：

public class EntityTypeDeserializerProvider : DefaultODataDeserializerProvider
{
    private readonly DataContractDeserializer _dataContractDeserializer;
    public EntityTypeDeserializerProvider(IServiceProvider rootContainer)
        : base(rootContainer)
    {
        _dataContractDeserializer = new DataContractDeserializer(this);
    }

    public override ODataEdmTypeDeserializer GetEdmTypeDeserializer(IEdmTypeReference edmType)
    {
        if(edmType.Definition.TypeKind == EdmTypeKind.Complex || edmType.Definition.TypeKind == EdmTypeKind.Entity)
            return _dataContractDeserializer;
        else 
            return base.GetEdmTypeDeserializer(edmType);
    }
}

与 provider 一样，您的自定义_Deserializer应该调用基本实现以实现不需要自定义的所有内容。在以下实现中，我们仅尝试强制反序列化的属性的顺序以及调用DataContract OnDeserializing和OnDeserialized方法，其他反序列化不受影响：< / p>

/// <summary>
/// OData serializer that oberys the DataMember Order Attribute and OnDeserializing and OnDeserialized attributes on the resource definition
/// </summary>
public class DataContractDeserializer : ODataResourceDeserializer
{
    public DataContractDeserializer(ODataDeserializerProvider provider)
        : base(provider) { }

    public override object CreateResourceInstance(IEdmStructuredTypeReference structuredType, ODataDeserializerContext readContext)
    {
        var resource = base.CreateResourceInstance(structuredType, readContext);
        var type = resource.GetType();
        if(type.GetCustomAttributesData().Any(x => x.AttributeType == typeof(DataContractAttribute)))
        {
            // manually call OnDeserializing
            var init = type.GetMethods(System.Reflection.BindingFlags.Instance | System.Reflection.BindingFlags.Public | System.Reflection.BindingFlags.NonPublic).FirstOrDefault(x => x.GetCustomAttributesData().Any(a => a.AttributeType == typeof(OnDeserializingAttribute)));
            if(init != null)
            {
                init.Invoke(resource, new object[] { new StreamingContext(StreamingContextStates.Remoting, readContext ) });
            }
        }
        return resource;
    }

    public override object ReadResource(ODataResourceWrapper resourceWrapper, IEdmStructuredTypeReference structuredType, ODataDeserializerContext readContext)
    {
        var resource = base.ReadResource(resourceWrapper, structuredType, readContext);
        var type = resource.GetType();
        if (type.GetCustomAttributesData().Any(x => x.AttributeType == typeof(DataContractAttribute)))
        {
            // manually call OnDeserialized
            var final = type.GetMethods(System.Reflection.BindingFlags.Instance | System.Reflection.BindingFlags.Public | System.Reflection.BindingFlags.NonPublic).FirstOrDefault(x => x.GetCustomAttributesData().Any(a => a.AttributeType == typeof(OnDeserializedAttribute)));
            if (final != null)
            {
                final.Invoke(resource, new object[] { new StreamingContext(StreamingContextStates.Remoting, readContext) });
            }
        }
        return resource;
    }
    public override void ApplyStructuralProperties(object resource, ODataResourceWrapper resourceWrapper, IEdmStructuredTypeReference structuredType, ODataDeserializerContext readContext)
    {
        var type = resource.GetType();
        var memberDescriptors = type.GetProperties().Where(x => x.HasAttribute<DataMemberAttribute>());
        if (memberDescriptors.Any())
        {
            var orderedProperties = from p in resourceWrapper.Resource.Properties
                                    let clsProperty = memberDescriptors.FirstOrDefault(m => m.Name == p.Name)
                                    let memberAtt = (DataMemberAttribute)(clsProperty?.GetCustomAttributes(true).FirstOrDefault(a => a.GetType() == typeof(DataMemberAttribute)))
                                    orderby (memberAtt?.Order).GetValueOrDefault()
                                    select p;
            foreach (var property in orderedProperties)
            {
                ApplyStructuralProperty(resource, property, structuredType, readContext);
            }
        }
        else
            base.ApplyStructuralProperties(resource, resourceWrapper, structuredType, readContext);
    }
}

最后，您需要用自己的注册表替换默认的 DeserializerProvider 注册，以下是MapODataServiceRoute的重载示例，该重载用于注册 DeserializerProvider 来自前面两个示例。
我已注释掉注册特定SerializerProvider的示例

private static ODataRoute MapODataServiceRoute(this HttpConfiguration configuration, string routeName,
    string routePrefix, IEdmModel model, ODataBatchHandler batchHandler = null, ODataUriResolver uriResolver = null, IList<IODataRoutingConvention> routingConventions = null)
{
     return configuration.MapODataServiceRoute(routeName, routePrefix, builder =>
         builder
             .AddService(ServiceLifetime.Singleton, sp => model)
             //.AddService<ODataSerializerProvider>(ServiceLifetime.Singleton, sp => new DefaultODataSerializerProvider(sp))
             .AddService<ODataDeserializerProvider>(ServiceLifetime.Singleton, sp => new EntityTypeDeserializerProvider(sp))
             .AddService(ServiceLifetime.Singleton, sp => batchHandler ?? new DefaultODataBatchHandler(GlobalConfiguration.DefaultServer))
             .AddService(ServiceLifetime.Singleton, sp => uriResolver ?? new ODataUriResolver())
             .AddService<IEnumerable<IODataRoutingConvention>>(ServiceLifetime.Singleton, sp =>
                     routingConventions ??
                         ODataRoutingConventions.CreateDefaultWithAttributeRouting(routeName, configuration)
                    )
                );
    }

Odata Webapi-如何在7.0内核中注入ODataResourceDeserializer？

1 个答案: