嵌套温文尔雅的WebPart

Question

我第一次玩Suave，显然有些东西我不明白。 我试图实现的是实现一个简单的 Rest API：

• 用户可以获取有关金融工具的信息
• 此外，每种工具都有价格清单

现在，为了简单起见，我只关注GET方法。

我最基本的代码段在这里：

[<AutoOpen>]
module RestFul =    
let JSON v =     
let jsonSerializerSettings = new JsonSerializerSettings()
jsonSerializerSettings.ContractResolver <- new CamelCasePropertyNamesContractResolver()
JsonConvert.SerializeObject(v, jsonSerializerSettings)
|> OK 
>=> Writers.setMimeType "application/json; charset=utf-8"
let fromJson<'a> json =
JsonConvert.DeserializeObject(json, typeof<'a>) :?> 'a    
let getResourceFromReq<'a> (req : HttpRequest) = 
let getString rawForm = System.Text.Encoding.UTF8.GetString(rawForm)
req.rawForm |> getString |> fromJson<'a>
type RestResource<'a> = {
GetById : int -> 'a option
GetPricesById : int -> 'a option
}
let rest resource =
let handleResource requestError = function
| Some r -> r |> JSON
| _ -> requestError
let getResourceById = 
resource.GetById >> handleResource (NOT_FOUND "Resource not found")
let getPricesById = 
resource.GetPricesById >> handleResource (NOT_FOUND "Resource not found")
choose [
GET >=> pathScan "/instrument/%d" getResourceById
GET >=> pathScan "/instrument/%d/prices" getPricesById
]

module Main =
[<EntryPoint>]
let main argv = 
let webPart = rest {
GetById = fun i -> Some i // placeholder
GetPricesById = fun i -> Some i // placeholder, it'll be a list eventually
}
startWebServer defaultConfig webPart
0

当我以这种方式定义 WebPart 时：

choose [
GET >=> pathScan "/instrument/%d" getResourceById // Returns the instrument static data
GET >=> pathScan "/instrument/%d/prices" getPricesById // Returns price list for the instrument
]

然后一切正常。我想知道是否有办法嵌套网络部件，例如这样：

// My idea about the code - doesn't compile
choose [
pathScan "/instrument/%d" getResourceById >=> choose [
GET // Returns the instrument static data
GET >=> path "/prices" >=> (somehow refer to the previous id and get prices)  // Returns price list for the instrument
]
]

另外 - 当我了解 RestAPI 时，我的推理可能存在差距。我认为以这种方式嵌套价格端点可以清楚地表明价格被认为是工具的属性(如果我错了，请随时纠正我(。

Answer 1

对，所以访问以前的请求是一种反温文尔雅的;)我们希望事情能够独立发生，无论刚刚发生了什么。因此，也许解决这个问题的更好方法是简单地将价格附加到路径的尽头？

choose [
GET >=> pathScan "/instrument/%d" getResourceById 
GET >=> pathScan "/instrument/%d/prices" getPricesById
]