MongoDB复合键:InvalidOperationException:{document} .Identity不受支持

Question

我遇到了保护一个类的问题,该类由一个复合ID组成,而该复合ID又有一个基类,我收到一个错误说法 InvalidOperationException: {document}.Identity is not supported.

我试图写入数据库的类如下:

public class Product : IEntity<Product>
{
    public readonly Sku Sku;
    public string Name { get; private set; }
    public string Description { get; private set; }
    public bool IsArchived { get; private set; }
    public Identity<Product> Identity => Sku;

    public Product(Sku sku, string name, bool isArchived)
    {
        Sku = sku;
        Name = name;
        IsArchived = isArchived;
    }
}

public interface IEntity<T>
{
    Identity<T> Identity { get; }
}

反过来有一个ID Sku,它是由下面的复合值(VendorId和一个本地Value内部Sku)组成的类:

public class Sku : Identity<Product>
{
    public readonly VendorId VendorId;
    public readonly string Value;

    public Sku(VendorId vendorId, string value)
    {
        VendorId = vendorId;
        Value = value;
    }

    protected override IEnumerable<object> GetIdentityComponents()
    {
        return new object[] {VendorId, Value};
    }
}

public class VendorId : Identity<Vendor>
{
    public readonly string Value;

    public VendorId(string value)
    {
        Value = value;
    }

    protected override IEnumerable<object> GetIdentityComponents()
    {
        return new object[] {Value};
    }
}

我有一个我的实体的基类,我Identity在我的DDD库中使用,基本上这里的ToString()输出可以用作ID,如果这会简化事情:

public abstract class Identity<T> : IEquatable<Identity<T>>
{
    public override bool Equals(object obj) { /* snip */ }
    public bool Equals(Identity<T> other) { /* snip */ }
    public override int GetHashCode() { /* snip */ }

    public override string ToString()
    {
        var id = string.Empty;

        foreach (var component in GetIdentityComponents())
        {
            if (string.IsNullOrEmpty(id))
                id = component.ToString(); // first item, dont add a divider
            else
                id += "." + component;
        }

        return id;
    }

    protected abstract IEnumerable<object> GetIdentityComponents();
}

我在app start上注册了映射:

// rehydrate readonly properties via matched constructor
// https://stackoverflow.com/questions/39604820/serialize-get-only-properties-on-mongodb
ConventionRegistry
    .Register(nameof(ImmutablePocoConvention), new ConventionPack { new ImmutablePocoConvention() }, _ => true);

BsonClassMap.RegisterClassMap<Product>(cm =>
{
    cm.AutoMap();
    cm.MapIdMember(c => c.Sku);
});

BsonClassMap.RegisterClassMap<Vendor>(cm =>
{
    cm.AutoMap();
    cm.MapIdMember(c => c.Id);
});

但是,当我去写,我得到 InvalidOperationException: {document}.Identity is not supported.

// my respositoru method
public void Upsert<T>(T entity) where T : IEntity<T>
{
    this.Database
        .GetCollection<T>(product.GetType().FullName)()
        .ReplaceOneAsync(x=>x.Identity.Equals(entity.Identity), entity, new UpdateOptions() {IsUpsert = true})
        .Wait();
}

var product = new Product(new Sku(new VendorId("dell"), "12434" ),"RAM", false );
myProductRepo.Upsert(product);

不确定这是否因为我直接从我的实体层持续存在而过于复杂(或者如果我只使用自动化器和更简单的POCO)......或者如果我缺少一些映射指令.

感谢任何帮助或指针.

Answer 1

我正在通过构造函数查看水合作用，这是通过GetProperties.

所以public readonly Sku Sku;不会显示出来，classMap.ClassType.GetTypeInfo().GetProperties(_bindingFlags)因为它只能作为成员字段访问。

您可以将其更改为public Sku Sku { get; }通过构造函数进行水合GetProperties，并将所有只读字段（Sku - VendorId, Value＆VendorId - Value字段）更改为具有属性 getter 方法。

另外，您还必须添加cm.MapProperty(c => c.Identity)sox=>x.Identity.Equals(entity.Identity)用作表达式时可以序列化，因为在自动映射逻辑运行时它不是构造函数参数，因此Identity无法水合和注册。ImmutablePocoConvention

代码更改：

public class Sku : Identity<Product>
{
    public VendorId VendorId { get; }
    public string Value { get; }
}

public class VendorId : Identity<Vendor>
{
    public string Value { get; }
}

BsonClassMap.RegisterClassMap<Product>(cm =>
{
   cm.AutoMap();
   cm.MapIdMember(c => c.Sku);
   cm.MapProperty(c => c.Identity);
});