将JsonPatchDocument移到复杂的Entity Framework跟踪对象上 [英] JsonPatchDocument onto a complex Entity Framework tracked object

问题描述

我正在尝试使用Json补丁来更新存储在Entity Framework数据上下文中的实体.

I am trying to use Json patches to update entities stored in an Entity Framework data context.

我有这样的实体类-

public class Customer
{
    public Guid Id { get; set; }

    public string Name { get; set; }

    public virtual ICollection<Quote> Quotes { get; set; }
}

public class Quote
{
    public Guid Id { get; set; }

    public int Order { get; set; }

    public string Status { get; set; }
}

要将补丁应用到 Customer 对象上，我从数据上下文中查询源，然后应用补丁，就像这样-

To apply the patch onto a Customer object, I query the source from the data context, then apply the patch, like so -

var entity = dataContext.Customers.Find(id);

patch.ApplyTo(entity);

dataContext.SaveChanges();

其中 patch 由-

[{ "op": "replace", "path": "/name", "value": "new name" }]

这对于源对象的简单更新效果很好，当我想修补链接的实体时，会出现问题，请考虑以下修补程序

This works fine for simple updates on the source object, the problem arises when I want to patch onto the linked entities, consider the following patch

[{ "op": "replace", "path": "/quotes/0/status", "value": "Closed" }]

我面临的第一个问题是-

The first issue that I am faced with is -

找不到路径段'0'指定的目标位置

The target location specified by path segment '0' was not found

我发现的唯一解决方法是调用将查询实体的方法从上下文更改为-

The only way around this I have found is to call the alter the way of querying the entity from the context to -

var entity = dataContext.Customers
    .Include(ent => ent.Quotes)
    .SingleOrDefault(ent => ent.Id == id);

entity.Quotes = entity.Quotes.OrderBy(ent => ent.Order).ToList);

哪个不理想，因为我不喜欢查询数据以更新数据的想法.我想知道是否有一种更清洁的方法.

Which is less than ideal, as I don't like the idea of querying data to update it. I'm wondering if there is a cleaner approach to this.

推荐答案

这是我找到的解决方案- https://gist.github.com/brendanmckenzie/a50f4eb7d5913372d01fef8e73c5dc9b

This is the solution I landed on - https://gist.github.com/brendanmckenzie/a50f4eb7d5913372d01fef8e73c5dc9b

该代码处理创建和更新存储在实体框架中的实体.当EF跟踪JsonPatch应用的更改时，修补工作效果很好.

The code handles creating and updating entities stored in Entity Framework. Patching works well as EF tracks the changes applied by JsonPatch.

其中还有一些杂乱的代码( NormaliseOperations )，有助于处理链接的实体；即例如 Quote 引用另一个实体的示例.

There is some additional code in there that's a bit messy (NormaliseOperations) that helps deal with linked entities; i.e., example if Quote referenced another entity.

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