长颈鹿 routef 异步函数

Question

我一直在使用 f# 创建 Giraffe api 服务器，并且很高兴地使用了 route 函数：

type Person = { id: BsonObjectId; name: string; age: int; }

let getPeople (databaseFn: unit-> IMongoDatabase) : HttpHandler =
    fun (next : HttpFunc) (ctx : HttpContext) -> 
        let database = databaseFn()
        let collection = database.GetCollection<Person> "people"
        task {
            let! cursor = collection.FindAsync<Person>(fun p -> true)
            let! hasMoved = cursor.MoveNextAsync()
            let result = 
                match hasMoved with
                | true -> json cursor.Current next ctx
                | false -> 
                    let message = { message = "No People found" }
                    RequestErrors.notFound (json message) next ctx
            return! result
        }

let savePerson (databaseFn: unit -> IMongoDatabase ) : HttpHandler =
    fun (next : HttpFunc) (ctx : HttpContext) -> 
        let database = databaseFn()
        let collection = database.GetCollection<Person> "people"
        task {
            let serialiser = ctx.GetJsonSerializer()
            let! person = ctx.BindJsonAsync<Person>()
            let personWithId = { person with id = BsonObjectId ( ObjectId.GenerateNewId() ) }
            do! collection.InsertOneAsync(personWithId)
            return! text "nailed it" next ctx
        }

let deletePerson (databaseFn: unit -> IMongoDatabase ) = 
    fun (id: string) -> 
        let database = databaseFn()
        let collection = database.GetCollection<Person> "people"
        task {
            let oId = BsonObjectId (ObjectId id) 
            let! result = collection.FindOneAndDeleteAsync<Person>(fun p -> p.id = oId)
            return text "awesomesauce"
        }

let personHandler getPeople savePerson deletePerson = 
    let path = "/people"
    choose [
        GET >=> choose [
            route path >=> getPeople
        ]
        POST >=> choose [
            route path >=> savePerson
        ]
        DELETE >=> choose [
            routef "/people/%s" >=> deletePerson
        ]
    ]

但我添加了 deletePerson 处理程序，但它现在抱怨

routef "/people/%s" >=> deletePerson

The type 'HttpFuncResult' does not match the type 'HttpHandler'

我知道类型不匹配，但是当我这样使用它时

routef "/people/%s" deletePerson

它抱怨 deletePerson 函数 returns System.Threading.Tasks.Task<(HttpFunc -> HttpContext -> HttpFuncResult)> 而不是 HttpHandler

我只是不确定我如何拥有 routef 我可以从路由参数中获取值并一次性拥有一个异步 HttpHandler？

Answer 1

我没有导入所有类型来编译整个东西，但我认为你需要从 delete:

中删除 >=>

DELETE >=> choose [
   (routef "/people/%s" deletePerson)
]

deletePerson 签名为：

let deletePerson (databaseFn: unit -> IMongoDatabase ) (id: string) : HttpHandler = 
    fun (next : HttpFunc) (ctx : HttpContext) -> 
        let database = databaseFn()
        //etc

长颈鹿 routef 异步函数

giraffe routef async function

f#

f#-giraffe