f# – 在Suave中聚合来自请求的信息

我正在使用Suave构建经过身份验证的Web API,我经常偶然发现在不同功能中聚合信息的问题

pathScan Navigation.playersAvailables GetGame >>= getInSession >>= (fun (gameId,playerInSession) -> //access to both gameId and player in session)

签名：

getGame : HttpContext -> Async<HttpContext option>
getInSession : HttpContext -> Async<HttpContext option>

> getGame从httpContext.request.querystring getInSession获取id
>从httpContext.cookie获取sessionId

我发现这样做的唯一方法是在userDataDictionnary中存储信息：

Writers.setUserData "player"  { playerId= playersId; socialId=socialId; username = username}

并在其他功能中检索它,但它看起来非常讨厌我：

let player = x.userState.["player"] :?> PlayerSession
//do some other stuff now that we have the current player

还有另一种方法吗？我想拥有像这样的纯粹功能
getGameId并获取Session等等.并且能够组合它们,因为我希望处理我的不同路线：

pathScan Navigation.playersAvailables GetGame >>= getInSession >>= (fun (gameId,playerInSession) -> //access to both gameId and player in session)
pathScan Navigation.otherRoute GetGame >>= (fun (gameId) -> //process gameId)
pathScan Navigation.otherRoute2 getInSession >>= (fun (sessionId) -> //process sessionId to do some other stuff)

我担心我需要的是与一些真正的函数程序员进行一天的谈话..

setUserData是一个纯函数– src.

不确定this是否仍然是最新的,但它表示pathScan和>> =不能很好地链接.但是我认为您正在使用的Writers.setUserData可能能够实现它.

进入一个物品袋以拉出东西并不可爱.

怎么样：

let (|ParseInt|_|) =
    function
    | "" | null -> None
    | x ->
        match Int32.TryParse x with
        | true, i -> Some i
        | _ -> None


let (|HasParam|_|) name (ctx:HttpContext) =
    ctx.request.queryParam name
    |> function
        |Choice1Of2 value ->
            Some value
        | _ -> None

let playersAvailablePart:WebPart =
    function
    //access to both gameId and player in session
    |HasParam "inSession" playerInSession & HasParam "gameId" gameId as ctx ->
        // do your processing here, sample return:
        OK "we had all the required important parts" ctx
    // or an example of something more strongly typed
    | HasParam "inSession" (ParseInt playerInSession) & HasParam "gameId" (ParseInt gameId) as ctx ->
        // do your processing here, sample return:
        OK "we had all the required important parts" ctx
    | ctx -> never ctx

如果值不在queryParameters中,则这不完全有效,但您可以将其调整到它们所在的位置