c# - 在 c# webapi 中创建超媒体的正确方法

Question

我正在研究如何为特定资源实现超媒体，但找不到真正的实现示例，只是抽象...

你知道，在各种文章中，这个人创建了如下方法:

public List<Link> CreateLinks(int id)
{
    ...//Here the guy put these three dots, whyyyyyyyyyy?
}

我目前拥有的:

public Appointment Post(Appointment appointment)
    {
        //for sake of simplicity, just returning same appointment
        appointment = new Appointment{
            Date = DateTime.Now,
            Doctor = "Dr. Who",
             Slot = 1234,
            HyperMedia = new List<HyperMedia>
            {
                new HyperMedia{ Href = "/slot/1234", Rel = "delete" },
                new HyperMedia{ Href = "/slot/1234", Rel = "put" },
            }
        };

        return appointment;
    }

还有约会类:

public class Appointment
{
    [JsonProperty("doctor")]
    public string Doctor { get; set; }

    [JsonProperty("slot")]
    public int Slot { get; set; }
    [JsonProperty("date")]
    public DateTime Date { get; set; }

    [JsonProperty("links")]
    public List<HyperMedia> HyperMedia { get; set; }
}

public class HyperMedia
{
    [JsonProperty("rel")]
    public string Rel { get; set; }

    [JsonProperty("href")]
    public string Href { get; set; }
}

有没有合适的方法呢？我的意思是，没有对链接进行硬编码？如何为给定类型(即约会类)动态创建它们？

我使用的是 c# Webapi，而不是 c# MVC。

Answer 1

1. 要将路由动态添加到 HyperMedia 集合，您可以使用路由命名:

   • 使用特定名称定义您的路线(例如删除):

     [Route("{id:int}", Name = "AppointmentDeletion")]
     public IHttpActionResult Delete(int slot)
     {
         //your code
     }
     

   • 使用UrlHelper.Link方法:

     public Appointment Post(Appointment appointment)
     {
         appointment = new Appointment
         {
             HyperMedia = new List<HyperMedia>
             {
                 new HyperMedia
                 { 
                     Href = Url.Link("AppointmentDeletion", new { slot = 1234 }), 
                     Rel = "delete" 
                 }
             }
     
         return appointment;
     }; 
     

2. 也可以在不为每个类声明 HyperMedia 属性的情况下向结果对象动态添加链接:

   • 定义一个没有链接的类:

     public class Appointment
     {
         [JsonProperty("doctor")]
         public string Doctor { get; set; }
     
         [JsonProperty("slot")]
         public int Slot { get; set; }
     
         [JsonProperty("date")]
         public DateTime Date { get; set; }
     } 
     

   • 定义一个扩展方法:

     public static class LinkExtensions
     {
         public static dynamic AddLinks<T>(this T content, params object[] links)
         {
             IDictionary<string, object> result = new ExpandoObject();
     
             typeof (T)
                 .GetProperties(BindingFlags.Public | BindingFlags.Instance)
                 .ToList()
                 .ForEach(_ => result[_.Name.ToLower()] = _.GetValue(content));
     
             result["links"] = links;
     
             return result;
         }
     }
     

   • 使用它:

     public IHttpActionResult Post(Appointment appointment)
     {
         return Ok(appointment.AddLinks(new HyperMedia
         { 
             Href = Url.Link("AppointmentDeletion", new { slot = 1234 }), 
             Rel = "delete" 
         }));
     }